Dissertations / Theses: 'New Zealand. Agricultural Research Division'

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Sheldon-Sayer, Lynne. "The vegetation of Maud Island, Marlborough, New Zealand." Lincoln University, 2006. http://hdl.handle.net/10182/1707.

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Maud Island (Te Hoiere - "a long paddle or mighty pull") is a moderately sized island of 309 hectares, located in the Pelorus Sound (41°, 02 'S, 173° 54 'E) Marlborough, at the north-east end of the South Island of New Zealand. It has a long history of human modification and impacts since its colonisation by Maori and early Europeans. The vegetation of Maud Island has been studied in the 1980's and again in the early 1990's. The objectives of this study were to (1) describe how the vascular plant communities vary in species composition across Maud Island, (2) determine which environmental factors are important predictors of the variation in species composition of Maud Island plant communities, and (3) describe the pattern of succession of the plant communities on Maud Island over the last twenty years. In this 2001 study, I comprehensively sampled the vegetation on Maud Island using a Reconnaissance Description Procedure in a total of 158 plots across the island and compared these results to previous descriptions. I also retook photos at permanent photo points to provide a visual comparison of vegetation change. In total, 219 plant species were identified; 177 species occurred within the plots and 42 additional species were observed while walking around the coastline and walking tracks. Six dominant plant species occurred in over 70% of the plots. They were Pteridium esculentum, Pseudopanax arboreus, Hebe stricta var. stricta, Melicytus ramiflorus, Ozothamnus leptophylla and Coprosma robusta. Two-Way Indicator Species Analysis resulted in the description of eight different plant communities on the island. Detrended correspondence analysis showed a high degree of turnover in species composition among these communities. Canonical correspondence analysis showed that slope and moisture were particularly important predictors of variation in plant species composition. The environmental factors that best predicted to variation communities were slope, moisture, and a gradient in historical disturbance. Comparisons of present and past vegetation maps and photos (ground and aerial) showed, in terms of the successional pathways of the vegetation on Maud Island, that over time, the vegetation is reverting from short stature grassland and scrub to predominantly forest scrub and young secondary forest.

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Reiser, Axel. "Resource efficiency of the ski industry in New Zealand." Lincoln University, 2002. http://hdl.handle.net/10182/1266.

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Skiing and snowboarding are popular recreation activities in New Zealand, as well as constituting important components of the winter tourism product. The 2001 snow season witnessed record visitor numbers. Skier days have increased by more than 10% compared with the previous year to 1.254 million. The traditionally “nature related” activity of skiing, however has increasingly often been discussed in the light of excessive resource consumption and pollution of alpine environments. Since no research on resource efficient management of ski fields has been undertaken in New Zealand, this study examined environmental awareness and actions of ski field managers, resource consumption benchmarks (water and energy use, solid waste production), along with resource use related visitor behaviour. Two separate surveys were undertaken to collect relevant information from ski field managers and ski field visitors. While a census of managers across New Zealand was conducted with a mail-back questionnaire (all 27 ski fields were contacted, response rate 44%), the visitor survey was undertaken on-site at six selected ski fields in Canterbury, South Island (total responses: N=259). Analysis of the survey results showed that managers generally acted to protect the environment and resources, however, at different levels for the various indicators measured. Energy use and air pollution were rarely perceived to be environmentally important. Accordingly, only few actions were undertaken to reduce energy use. This is surprising, since energy consumption proved to be a major feature of ski field management. Given the additionally large amounts of water consumed (mainly for snowmaking) and solid waste produced on the mountain, skiing has to be classified as a resource intensive activity. Resource consumption is intensified further, when the impacts associated with tourists being transported to, and from, the mountain are considered. Energy use for “ski trip transport” within New Zealand is two times larger (180 MJ) than energy use associated with ski field infrastructure use (90 MJ) on a per skier day basis. There are several options to improve the environmental performance of ski fields, ranging from modernising equipment, optimising snowmaking and providing efficient transport alternatives. Additionally, increased cooperation between ski field managers, local governments and research institutes could potentially result in environmentally smarter operational practices. Internationally, New Zealand’s ski areas compare relatively well, mainly because of limited on-mountain entertainment and accommodation development, which keeps resource consumption and pollution low compared with European and North American ski fields. However, this research also indicated that New Zealand’s ski field visitors increasingly demand facilities and services similar to those overseas, which in turn may result in larger environmental impacts. New Zealand is generally believed to be a green and nature-related destination and its ski areas still blend well into the natural environment. Hence, there is some potential for the New Zealand ski industry to develop a unique product in such a way that it is both, sustainable and distinguishable from other international markets.

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Becken, Susanne. "Energy use in the New Zealand tourism sector." Phd thesis, Lincoln University, 2002. http://hdl.handle.net/10182/440.

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Energy use associated with tourism has rarely been studied, despite a potentially considerable contribution to global or national energy demand and concomitant greenhouse gas emissions. In New Zealand, tourism constitutes an increasingly important economic sector that is supported by the Government to induce further economic growth. At the same time New Zealand is facing the challenge of reducing currently increasing fossil fuel combustion and carbon dioxide emissions. As a response, this study investigated the contribution tourism makes to energy use in New Zealand. In particular it has examined the role of the three main tourism subsectors (transport, accommodation, and attractions/activities), and different domestic and international 'tourist types'. Seven separate data analyses provided inputs for building a model based on 'tourist types' from which energy use in the New Zealand tourism sector could be estimated. Tourism was found to contribute at least 5.6% to national energy demand, which is larger than its 4.9% contribution to GDP in 2000. Transport, in particular domestic air and car travel, was identified as the dominant energy consumer. Within the accommodation sub-sector, hotels are the largest energy consumers, both in total and on a per visitor-night basis. Of the three sub-sectors, attractions and activities contribute least to energy use, however, activities such as scenic flights or boat cruises were recognised as being energy intensive. As a result of larger visitor volumes, domestic tourists contribute more to energy consumption than international tourists. Domestic and international tourists types differ in their energy consumption patterns, for example measured as energy use per travel day. Tourist types that rely on air travel are the most energy intensive ones, for example the domestic 'long air business' travellers or the international 'coach tourists'. The importance of international tourists' energy use will increase, given current growth rates. There are many options to decrease energy use of the tourism sector, with the most effective ones being within the energy intensive transport sub-sector. Increasing vehicle efficiencies and decreasing travel distances appear to be the most promising measures. This study argues that energy use depends largely on tourists' travel behaviour. Changing behaviour is possible but is postulated to be very difficult, and further research is needed to better understand tourists' motivations, expectations and decision-making. Only then, can strategies be developed and implemented to alter travel behaviours to better balance energy use, other environmental impacts and economic yield. Such a balance is a crucial consideration in the search for more sustainable forms of tourism.

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Thull, Jean-Paul. "Management of stock effluent spillage from trucks in New Zealand." Lincoln University, 1999. http://hdl.handle.net/10182/778.

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The key objective of this multi-disciplinary research was to seek for feasible solutions to avoid effluent from livestock trucks spilling onto roads. Stock effluent spillage mainly poses road safety hazards and environmental damage, and also causes offence to road users and tourists. This task required reviewing previous institutional actions, assessing the power of the existing legislation, and evaluating the interests and attitudes of the stakeholder groups involved in the overall livestock supply chain. It was also necessary to consider politics, administration, public policy and economics, gaining the willing cooperation and confidence of the stakeholder groups through application of 'Soft Systems Methodology' (SSM). A key component was the creation of a 13 minute video and its associated brochure as a primary tool for a stakeholder educational awareness programme. It was necessary to analyse the complex relationships between livestock preparation prior to transport; effluent produced in-transit; and end product quality factors. Detailed information pertaining to the nature of livestock shipments by truck in the South Island of New Zealand had to be collected and verified. All the above information were fed into the calculation of an ideal network of in-transit effluent discharge sites on State Highways in the South Island of New Zealand. Assuming the adoption of best practice throughout the supply chain, it was possible to recommend sustainable solutions. The problem is amenable to solution. Adoption of a strong Industry Code of Practice, coupled with the construction of a strategic network of dump sites will enable the industry to avoid the heavy-handed legal consequences of allowing the status quo to continue.

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Calder, Keith Wallace. "A LEEP forward : biodiversity futures for New Zealand : a thesis in partial fulfilment of the requirements for the Master of Resource and Environmental Planning at Massey University, Palmerston North, New Zealand." Massey University, 2007. http://hdl.handle.net/10179/741.

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Loss of indigenous biodiversity continues in New Zealand. Despite admirable goals in the NZBS 2000 to the contrary, efforts at improved biodiversity conservation have been insufficient to halt loss of significant amounts of indigenous forest and wildlife habitat. Increasing numbers of native species are moving towards critically endangered and extinction. Whatever we are doing in New Zealand, it is not effective enough. The aim of this study is to firstly identify factors contributing to the failure, “to halt the decline of indigenous biodiversity” in New Zealand and to then consider opportunities to overcome these barriers. In considering opportunities, this study then reviews the emerging discipline of landscape ecology as an answer to, at least, some of those factors and the recurring calls from New Zealand ecologists for a more integrated and holistic approach to biodiversity conservation. Recent advances in the planning framework and particularly provisions for biodiversity conservation in England are explored as a model of practical application of landscape ecological principles to land-use planning. From this review, the study proposes a new ‘LEEP’ model for strategic biodiversity conservation that produces a regional-scale spatial conservation map and accompanying policy and implementation guide. Together they provide an integrated and holistic approach to restoring or creating functional landscapes that also recognises and provides for human activities and development. Application of the LEEP model is demonstrated through a case study of the Wellington region. Benefits and potential uses of the map and policy outputs are canvassed. Interviews with leading New Zealand and international ecologists provide an assessment of the current status of landscape ecology and interviewees also act as an expert ‘test panel’ against which the Wellington maps and guides produced from the ‘LEEP’ model are assessed. Finally, suggestions are provided for development of the new model and future research needs towards fuller and more effective implementation of this approach to biodiversity conservation in the New Zealand context.

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Thomas, Craig W. "Current practices and future possibilities of performance recording extensively-grazed commercial beef herds in New Zealand." Diss., Lincoln University, 2008. http://hdl.handle.net/10182/844.

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There is little evidence that the productivity of New Zealand beef herds has improved over time. Data from the NZ Meat and Wool Board’s Economic Service (2006) suggest that the average national calving percentage has declined over the last two decades. During the same period cattle carcass weights have increased but so too has the average cow live-weight which has resulted in increased maintenance costs of the cow herds. It is unclear whether production efficiency in the industry has improved or declined over time. The aim of this research was to develop means of improving productivity in commercial beef herds through practical methods of performance recording. The objectives were firstly to establish current management practices in commercial herds and secondly to develop an objective system for cow selection and culling which would have practical application in commercial herds. Beef management survey Ninety two commercial beef producers with more than 100 breeding cows from the greater Canterbury region of New Zealand were surveyed. Pasture control was the main reason given for owning a beef herd. Size and conformation were the main selection criteria for choosing replacement heifers and bulls. Over 80% of herds retained their own heifers as replacements and >60% mated yearling heifers to first calve at two years of age. Fertility was poor in the surveyed herds. In-calf rates at pregnancy testing averaged 88% for maiden heifers, 92% for rising second calvers and 93% for mixed age (m.a.) cows. There was no significant difference between in-calf rates of maiden heifers mated to first calve at two or three years of age; nor was there any significant difference between the re-breeding success of the two groups. Heifers mated at least one week earlier than m.a. cows, achieved a re-breeding success 4.7% greater (P<.01) than those mated at the same time. Reasons for cows not weaning a calf included wet dry (9.3% of pregnant cows wintered), pregnancy tested not-in-calf (7.4%) and dam death (2.6%). Only 87.9% of pregnant females wintered weaned a calf (89.4% of m.a. cows and 84.9% of heifers). Reasons why cows exited the herds included diagnosed empty (37.2% of all exits), involuntary culls (25.4%), sold wet dry (16.2%), deaths (13.1%) and poor calf production (5.1%). Vaccination was infrequent with clostridial vaccines the most common in m.a. cows (15.2%) and in calves (40.7%); vaccination against Leptospirosis was much less common. Very few of the surveyed farms used any system of performance recording; as a result there was very little performance-based selection or culling practiced. Evaluation of alternative measures of cow productivity Data from four performance recording beef herds were used to compare alternative measures of cow productivity with the industry standard which is calf weaning weight adjusted for sex (SOC) and age of calf and age of dam (AOD), i.e. the “200 day weight.” None of the alternative measures evaluated required knowledge of calving date and all were relatively easily obtainable in extensively managed beef herds. The assessment of cows was based not on their estimated breeding values but instead on their most probable producing ability which, as the sum of all of the permanent, repeatable aspects of the calf-rearing ability of the cow, explains considerably more of the variance of weaning weight than does breeding value alone. SOC and AOD-adjusted marking weight, weaning weight and average daily gain (ADG) between marking and weaning were the traits mostly highly correlated with the 200d wt of calves (r = 0.68, 0.90 and 0.74. respectively). An Extensively- Grazed-Cow-Weaning-Index of these three indicator traits was found to be more highly correlated than any of the individual traits on their own (r = 0.94). Index weights for the three indicator traits were calculated within each herd and then those within-herd index weights were regressed on readily obtainable herd descriptive variables to obtain a regression equation that could predict index weights for any herd. When the model was applied to data from two additional herd years not included in the original model, the EGCW Index was highly correlated with the 200d weights (r>0.90). Performance-based culling of previously unselected commercial beef herds based on the EGCW Index will result in improved productivity due to the moderately high repeatability of calf weaning weight. Objective data from extensively grazed commercial herds will also make possible the use of commercial herd data in genetic evaluations of herd sires.

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Menzies, Diane. "Clean and green? Environmental quality on the New Zealand dairy farm." Lincoln University, 1999. http://hdl.handle.net/10182/1553.

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This study explores issues arising from the adoption of the term 'clean and green' for marketing New Zealand dairy products. Three dimensions of environmental quality were investigated: that of sustainable dairying and best practice for the benefit of farmers and the industry; resource management legislation and being a 'good neighbour'; and export marketing opportunities and issues. The study was undertaken during a time of major structural upheaval in the dairy industry, including yearly company amalgamations in the study area, rapid conversion of farmland to dairying, as well as factory expansion to process the increasing supply of product. The focus of the study was on the individual farmer, how perceptions and preferences are formed, and how in turn, these influence farm practice. World views drawn from Cultural Theory were adopted as the basis for analysis. Farmers were classified according to particular world views and the symbolic and reflexive use of concepts such as 'clean and green' was analysed. A model of overlapping ecological, agricultural and social systems was used to develop a wider understanding of preference formation. Through a mixed methodology, focusing on a case study approach, farmer and stakeholder world views were compared on key themes, including the 'clean green' pastoral myth, 'cues for care' and environmental issues. Media discourse as well as consumer views were used to expand understanding of the context. The study found that both farmers (within their groups) and stakeholders held different objectives and opinions on environmental issues and options for change, based on their various world views and preferences. There was general agreement both among farmers and stakeholders on the New Zealand 'clean green' image and 'cues for care', or signs that indicate good farm management. The reason for this was demonstrated to be the way in which these two aspects are communicated; through symbolic images that each individual perceived in terms of their respective world view. A symbolic form of action, an environmental management system, was trialled with farmers. Analysis indicated that national aspirations created by the 'clean green' pastoral myth required farmers to respond to environmental expectations, but that an image that symbolized environment as care and quality, rather than as place was needed to provide a less ambiguous goal. The findings of the trial were integrated with theory to interpret context and develop policy, strategy and action proposals for a system for environmental quality for the industry. The study has implications for non-regulatory mechanisms relevant to sustainable dairy farming, communication within the rural community, and branding.

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Willems, Nancy. "Forest structure and regeneration dynamics of podocarp/hardwood forest fragments, Banks Peninsula, New Zealand." Lincoln University, 1999. http://hdl.handle.net/10182/1301.

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Although species maintenance in small forest fragments relies on successful regeneration and recruitment, few studies have examined the effects of fragmentation on regeneration processes. New Zealand's podocarp species rely on large disturbance openings operating across a vegetated landscape to stimulate regeneration. Clearance of vegetation that results in small fragments of forest removes regeneration opportunities for podocarps by destroying the intact vegetation mosaic, and as a result may exclude disturbances of the scale necessary for podocarp regeneration. Fragmentation alters the disturbance regime of the landscape, with important implications for the regeneration of podocarps on Banks Peninsula. The four remaining lowland podocarp-hardwood fragments on Banks Peninsula were sampled to determine the structure and regeneration patterns of podocarps and to assess their long term viability. Density, basal area, and size and age class distributions were used to examine current composition, and in conjunction with spatial analysis, to identify past regeneration patterns and infer likely future changes in composition and population structure. Podocarp size and age class structures for three of the four fragments were characteristically even-sized and relatively even-aged (eg; Prumnopitys taxifolia c. 350 to 600 years), with little or no regeneration for approximately the last 200 years (old-growth fragments). Regeneration of the current podocarp canopy in the old-growth fragments may have been stimulated by flooding. The fourth younger fragment showed much more recent regeneration with Prumnopitys taxifolia, Podocarpus totara and Dacrycarpus dacrydioides mostly 80-160 years old, and substantial populations of seedlings and saplings, probably as a result of anthropogenic fire. In the absence of major disturbance the podocarp component in forest fragments on Banks Peninsula is likely to decline with composition shifting towards dominance by hardwood species. There is some evidence to suggest that canopy collapse will stimulate some podocarp regeneration within the fragments, however it appears to be unlikely that podocarps will persist on Banks Peninsula indefinitely within the fragments studied. There is an urgent need for more quantitative research in New Zealand fragmentation literature, and a need for more emphasis on processes. Banks Peninsula offers potential for a more landscape scale approach in forest management, and the maintenance of regenerating scrub in pockets about the Peninsula may offer the regeneration opportunities for podocarps that are lacking within protected fragments. My study took a quantitative approach in examining the effects of forest fragmentation on the demographics of podocarps and compositional change in forest fragments on Banks Peninsula.

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O'Connor, Katrina Marie. "The ecological footprint of international tourists in New Zealand : a thesis presented in partial fulfilment for the degree of Master of Applied Science in Natural Resource Management at Massey University, Palmerston North, New Zealand." Massey University, 2009. http://hdl.handle.net/10179/1124.

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Ecological Footprint Analysis (EFA) is a technique that was first developed by Wackernagel as a Ph.D. thesis in 1994, then further developed in combination with Rees and published (Rees & Wackernagel, 1995). EFA is employed in this study to assess the resource utilisation of international tourists visiting New Zealand. Tourism is one of the fastest growing industries in the world and the ecological sustainability of tourism is becoming more important term for managing tourism. This is becoming increasingly important with tourism identified as particularly as a significant contributor to carbon emissions. This study uses EFA to assess whether international tourists visiting New Zealand behave in a sustainable manner. Tourists are surveyed and classed into high, mid and low budget tourist types to gain a detailed account of their behaviour with particular reference to food, accommodation, transport, services, activities attractions, goods and waste. The EFA helps to identify areas of a tourist’s trip that have the greatest impact on the environment, thereby identifying ways to improve the sustainability of tourism in New Zealand. It was found that tourists generally consume more whilst on holiday than they do at home and more than New Zealand residents. The results show that international tourists’ behaviour is sustainable and New Zealand has the ecological carrying capacity to allow the number of international tourists to increase without incurring any significant ecological costs to the country. It was found that there is a positive relationship between ‘high’ income tourists and their ecological footprint and that independent travellers have a larger ecological footprint than the package travellers; however, package travellers have a larger food and housing ecological footprint than independent travellers. The energy footprint was the largest out of the six land types of a tourist’s ecological footprint. Food is the consumption category that is the largest contributor to a tourist’s ecological footprint.

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Ates, Serkan. "Grazing management of subterranean clover (Trifolium subterraneum L.) in South Island (New Zealand)." Diss., Lincoln University, 2009. http://hdl.handle.net/10182/1338.

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This study consisted of two sheep grazed dryland pasture experiments. Experiment l compared sheep production from 3-year-old cocksfoot based pastures grown in combination with white, Caucasian, subterranean or balansa clover with a ryegrass-white clover pasture and a pure lucerne forage. Sheep liveweight gain per head from each pasture treatment and the pure lucerne stand was recorded in the 2006/07 and 2007/08 seasons. The cocksfoot-subterranean clover pasture provided equal (381 kg LW/ha in 2006) or higher (476 kg LW/ha in 2007) animal production in spring and gave the highest total animal production (646 kg LW/ha) averaged across years of the five grass based pastures. However, total annual liveweight production from lucerne was higher than any grass based pasture mainly due to superior animal production during summer when lucerne provided 42-85% higher animal production than any of the grass based pastures. In Experiment 2, the effect of stocking rate (8.3 (low) and 13.9 (high) ewes + twin lambs/ha) and time of closing in spring on lamb liveweight gain, pasture production and subterranean clover seedling populations was monitored over 2 years for a dryland cocksfoot-subterranean clover and ryegrass-subterranean clover pasture in Canterbury. In both years, twin lambs grew faster (g/head/d) in spring at low (327; 385) than high (253; 285) stocking rate but total liveweight gain/ha (kg/ha/d) was greater at high (7.26; 7.91) than low (5.43; 6.38) stocking rate. Ewes also gained 0.5 and 1.5 kg/head at the low stocking rate in 2006 and 2007 respectively but lost 0.2 kg/head in 2006 and gained 0.3 kg/head at high stocking rate in 2007. Mean subterranean clover seedling populations (per m²) measured in autumn after grazing treatments in the first spring were similar at both low (2850) and high (2500) stocking rate but declined with later closing dates in spring (3850, 2950, 2100 and 1700 at 2, 4, 6, 8 weeks after first visible flower). Seedling populations measured in autumn after grazing treatments in the second spring were also unaffected by stocking rate (low 1290, high 1190) but declined with later closing dates in spring (1470, 1320 and 940 at 3, 5 and 8 weeks after first flowering, respectively). The effect of stocking rate and closing dates in spring on pasture and clover production in the following autumn was similar to the effects on seedling numbers in both years. However, clover production in the following spring was unaffected by stocking rate or closing date in the previous year at the relatively high seedling populations generated by the treatments. This was presumably due to runner growth compensating for lower plant populations in pastures that were closed later in spring. Subterranean clover runner growth in spring may not compensate in a similar manner if seedling numbers in autumn fall below 500/m². Mean annual dry matter production from cocksfoot and ryegrass pastures grown with and without annual clovers pasture production ranged from 6.4 to 12.4 t DM/ha/y but stocking rate (8.3 vs. 13.9 ewes/ha) during spring did not affect annual pasture production. Pastures overdrilled with annual clovers yielded 23-45% more dry matter production than pastures grown without annual clovers. The study confirms the important role of subterranean clover in improving pasture production and liveweight gains of sheep in dryland cocksfoot and ryegrass pastures. Lowering stocking rate from 13.9 to 8.3 ewes/ha was a less effective method of increasing seed production of subterranean clover in dryland pastures although it did lead to increased liveweight gain per head.

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Serra, Postiglione Virginia. "A comparative study of the sources of competitive advantage in the New Zealand and Uruguayan beef industries." Lincoln University, 2003. http://hdl.handle.net/10182/1115.

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According to Porter (1990), there are certain characteristics of a country that allow its industries to create and sustain competitive advantage, or prevent them from doing so. The objective of this study was to identify and compare the sources of competitive advantage or disadvantage for the Uruguayan and New Zealand beef industries. To accomplish these objectives, Porter’s Diamond Framework was selected as the theoretical framework to assess the competitive advantage of nations. Two case studies “the Beef Industry in Uruguay” and “the Beef Industry in New Zealand” were carried out. The information was obtained from secondary sources and open-ended interviews to key informants in both countries. Uruguay and New Zealand possess observable similarities, such as size, population, similar farmland area, and an economy based on agriculture with low levels of subsidies and trade regulations. In addition, the industries in both countries target the international market. Considering beef production, these countries produce beef based on pastures; hence, they have similar seasonal fluctuations in slaughter and in the product offered into the market. These similarities make these countries interesting to compare. On the other hand, Uruguay and New Zealand have differences. They are in different stages of economic development, and have cultural, sociological and educational differences. The beef industry is the most important economic activity in Uruguay, as can be illustrated by the resources allocated in this sector and in the volume and value of exported beef. In New Zealand, the beef industry is less important; however, it constitutes an excellent complementary activity for sheep and dairy productions. Both beef industries also have differences in their levels of productivity, stock compositions, stock categories, age of slaughtered animals, sanitary status, and locations in relation to markets. This suggests different sources of competitive advantage. The results show that the Uruguayan beef industry has a weaker diamond than its New Zealand counterpart does. However, the industry in Uruguay has been increasing the use of resources in comparison to other pastoral activities such as dairy and sheep. In contrast, the New Zealand beef industry, despite having a stronger diamond than the Uruguayan beef industry, has a secondary role behind the sheep and dairy industry. There are two clear limitations for the Uruguayan beef industry. First, the performance of the primary sector is poor. Second, the Uruguayan exported beef receives a lower price than the New Zealand product, and has difficulties for gaining access to certain markets. These two characteristics were identified as the most dissimilar for both industries. The selected research design and theoretical framework were adequate to accomplish the objectives. Although most of Porter’s findings were not supported in this study, using the framework allowed the development of an exhaustive analysis of the possible factors affecting the sources of competitive advantage in both industries. Comparing diamonds in different countries has not been done before; therefore, this research provides empirical evidence of the advantages and disadvantages of using this framework for international comparisons. Finally, the information presented in this research did not intend to suggest possible strategies or policies to increase the competitiveness of both industries. However, the results are likely to provide useful information for further studies in these industries.

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Chappell, Esta Monique. "Morphology, phylogeography and drumming behaviour of a New Zealand ground weta, Hemiandrus pallitarsis : a thesis presented in partial fulfillment of the requirements for the degree of Master of Science in Conservation Biology at Massey University, Palmerston North, New Zealand." Massey University, 2008. http://hdl.handle.net/10179/828.

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Species are one of the fundamental components of biology and the accurate delimitation of species is important in evolutionary, systematic and ecological studies, yet there is still confusion over how species can be recognised. Examining different characters allows multiple lines of evidence for successful and accurate species delimitation and identification. In this thesis, morphological, genetic and behavioural variation is investigated within an endemic species of ground weta, Hemiandrus pallitarsis, in the North Island, New Zealand. Twelve morphological characters were measured, and mitochondrial cytochrome oxidase I DNA sequences were analysed from populations across the distributional range of H. pallitarsis. Both methods provide no evidence of a species complex within H. pallitarsis. Instead, the morphometric results suggest females are significantly larger than males, and ground weta in Palmerston North are significantly smaller than weta further north. Additionally, genetic analyses found substantial population structuring, large genetic distances, and an historical south to north pattern of movement in the North Island. The pattern of vibratory drumming behaviour followed that predicted by morphology and geographic proximity – drumming signals were more similar between geographically close populations and did not match the patterns of genetic isolation. Overall, this thesis was able to show that H. pallitarsis is morphologically, genetically and behaviourally variable across the North Island.

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Al-Amer, Saleh Suliaman. "Nutritional and toxicological studies on New Zealand mutton bird meat (Puffinus griseus)." Lincoln University, 2009. http://hdl.handle.net/10182/1659.

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New Zealand mutton bird or tītī (Puffinus griseus and order procellariiformes) nest in New Zealand during the summer months, migrate to the northern hemisphere during May and return in September. Their eggs are laid during November and December and the chicks are hatched in the following January and February. Large numbers of them are harvested from April to May in New Zealand. They are wild seabirds annually harvested by Maori according to the customary rights agreement set by Treaty of Waitangi.NZ mutton birds also called Sooty Shearwaters are noted for their high proportion of body fat.These birds are interesting since its sole diet is based on krill and other small marine organisms that are potentially rich in n-3 fatty acids and other marine bioactive compounds. The proximate composition, fatty and amino acids and cholesterol content of mutton bird pectoral muscle were determined and compared with other common meat to explore the nutritional value of this New Zealand delicacy. The concentration of twenty two essential and toxic elements including silver (Ag), aluminium (Al), arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), manganese (Mn), lead (Pb), selenium (Se), potassium (K), calcium (Ca), magnesium (Mg), boron (B), iron (Fe), nickel (Ni), sulphur (S), sodium (Na) and cobalt (Co) and zinc (Zn) in mutton bird breast meat (Puffinus griseus) were measured over two years to evaluate its safety for human consumption. Persistent organochlorine, dichlorodiphenyltrichloroethane (DDT) and their metabolites, and aldrin and lindane were also measured.Twenty bird carcasses were purchased in both 2006 and 2007 from a local source. Meat samples from the pectoral muscle of two carcasses were pooled to generate 10 samples for each year. These were used for trace element analysis using inductively coupled plasma-mass spectrometry (ICP-MS). Trace elements were in the range of 0 to 1.09 mg/kg wet weight for Ag, 0 to 3.32 for Al, 0.17 to 0.79 for As, 0.01 to 0.07 for Cd, 0.03 to 0.15 for Cr, 3.56 to 4.88 for Cu, 0 to 0.15 for Hg, 0.22 to 0.50 for Mn, 0 to 0.09 for Pb, 0.66 to 1.18 for Se and 11.49 to 23.70 for Zn. In 2006, Ag, Al, Mn and Zn concentrations were significantly higher but Pb and Hg concentrations significantly lower compared to the 2007 samples (P < 0.05). Apart from one sample in 2006, all the samples were below the published maximum level for concern. However, our preliminary data indicated that the higher level of Cd and other metals in the skin of mutton bird may compromise the overall safety to humans consuming the skin of mutton birds. It is suggested that the evaluation of the metals in different parts and/or the whole mutton bird at different seasons is required to assure complete safety to the consumers.Furthermore, the nutritional value of mutton bird meat was studied over two harvesting seasons (2006 and 2007) to investigate the impact of seasonal variation. The moisture and carbohydrates contents ranged between 54.0 to 55.0 % and 2.8 to 3.0 %, respectively, and no seasonal effects were evident in these components. The values for fat and ash contents were higher and the protein content lower for birds harvested in 2007 compared with the 2006 values which ranged from 11.8 to 13.0, 10.3 to 11.7, and 20.3 to 18.5 % for fat, ash and protein content respectively. The major amino acids in mutton bird pectoral muscle were glutamate, aspartate, lysine, leucine, and arginine. Higher lysine concentrations and lower proline, cystein and methionine were found in mutton birds compared with the literature values for beef, lamb and pork. The essential amino acid content in mutton bird (43.8 and 44.9 % in 2006 and 2007, respectively) was slightly higher than those found in beef and lamb meats (42-43%).The major fatty acids detected were palmitic (C16:0), stearic (C18:0), oleic and isomers (C18:1), eicosenoic (C20:1), Docosahexaenoic acid (DHA) (C22:6), icosapentaenoic acid (EPA) (C 20:5) and these accounted for approximately 77% of the fatty acids. The 3/6 ratio of fats from pectoral muscle was 1.3. The cholesterol concentration varied slightly in the two years with 184.4±37.37and 134.4±25.55mg/100 g fresh weight for 2007 and 2008 respectively. Mutton bird was shown to contain significantly higher cholesterol content (134.4-184.4) than other common meat such as chicken (80.3-88.9), lamb (62.3), fish (52.79) and beef (51.97). Overall, the nutritional value of mutton bird muscle was similar to or superior to the traditionally protein sources such as seafood and red meat. Annual variations existed in the composition of Mutton bird pectoral muscle but this is not of nutritional consequence but might be a useful indicator for ecological events such as feed availability and other environmental issues. Mutton bird seems to be a good source of essential minerals, Zn and Fe compared with other traditional meats source. Mutton bird meat is nutritionally as good as the major sources of red or white meats. It may even have advantages over the other common meats (beef, lamb, fish and chicken) due to its high protein and monounsaturated fatty acids (omega n-3 and n-6) content. However, its high cholesterol content may represent a risk factor for some people.

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Walbert, Katrin. "Ectomycorrhizal communities associated with a Pinus radiata plantation in the North Island, New Zealand." Lincoln University, 2008. http://hdl.handle.net/10182/658.

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Aboveground and belowground ectomycorrhizal (ECM) communities associated with different age classes of the exotic plantation species Pinus radiata were investigated over the course of two years in the North Island of New Zealand. ECM species were identified with a combined approach of morphological and molecular (restriction fragment length polymorphism (RFLP) and DNA sequencing) analysis. ECM species richness and diversity of a nursery in Rotorua, and stands of different ages (1, 2, 8, 15 and 26 yrs of age at time of final assessment) in Kaingaroa Forest, were assessed above- and belowground; furthermore, the correlation between the above- and belowground ECM communities was assessed. It was found that the overall and stand specific species richness and diversity of ECM fungi associated with the exotic host tree in New Zealand were low compared to similar forests in the Northern Hemisphere but similar to other exotic plantations in the Southern Hemisphere. Over the course of this study, 18 ECM species were observed aboveground and 19 ECM species belowground. With the aid of molecular analysis the identities of Laccaria proxima and Inocybe sindonia were clarified. In the aboveground study, five species were found associated with P. radiata that were previously not reported with this host in New Zealand (Inocybe sindonia, Lactarius rufus, Lycoperdon gunii, Rhizopogon pseudoroseolus and Wilcoxina mikolae). Belowground, the species Psudotomentella sp., P. tristis, R. luteorubescens, Tomentella sp., Wilcoxina mikolae were found as new associates of P. radiata in New Zealand, additionally nine ECM types were found that could not be identified with molecular analysis. There was little correlation between the species fruiting and the species colonising root tips. Only seven species were found in common between the above- and belowground communities, furthermore the dominant species aboveground were not observed in the belowground ECM communities. The influence of host age on the above- and belowground ECM communities of different age classes of P. radiata plantations was investigated. The aboveground species richness increased from the nursery to the oldest age group investigated (26 yrs), while diversity increased to the 15 yr old age group and decreased slightly to the oldest stand. A clear sequence of ECM species changes was observed to be related to stand age with a growing complexity over the chronosequence. The belowground ECM communities showed a different picture and richness and diversity initially decreased from the nursery to the outplanting but increased thereafter. Belowground no change in ECM composition that was directly related to the age of the host was observed, but two distinct groups of ECM species were found – a 'young' and a 'plantation forest' group, with the respective discriminating species being Rhizopogon rubescens and Type unknown Basidiomycete/Amanita muscaria. Another aspect of the study was the fate of the nursery ECM species in the outplanting and the arrival of non-nursery species. The ECM communities of seedlings in the nursery were investigated in 2006 and these seedlings were followed up over eight assessments in the field for one year, furthermore data from the 1-, 2 and 8 yr old plantation stands was analysed. It was found that the nursery species do survive the first year of outplanting and are dominant in the first year. The first non-nursery species occurred six months after outplanting but was only in minor abundance. Nursery ECM were dominant for two years after the seedlings were planted, and were completely replaced after seven years. Rhizopogon rubescens was found to be the most persistent and dominant species in the outplanting, facilitating the successful establishment of the seedlings in the plantation forest.

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15

Puig, Virginia Moreno. "Conservation issues for Hochstetter's frog (Leiopelma hochstetteri): monitoring techniques and chytridiomycosis prevalence in the Auckland region, New Zealand : a thesis presented in partial fulfillment of the requirements for the degree of Master of Science in Conservation Biology at Massey University, Auckland, New Zealand." Massey University, 2009. http://hdl.handle.net/10179/1132.

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Amphibians are suffering extinctions and range contractions globally. This is caused by numerous factors and most of them are related to human activities. The overall aim of this thesis was to make a significant contribution to the conservation of the endemic amphibian Leiopelma hochstetteri through research. This was achieved by focusing in two of the main conservation issues for this species, the need for standardised and robust monitoring techniques to detect trends and changes in populations, and the determination of the prevalence of chytridiomycosis, caused by the amphibian chytrid fungus (Batrachochytrium dendrobatidis). Two populations of the Auckland Region were selected for this study, one on the mainland (Waitakere Ranges) and the only known offshore island population of this species (Great Barrier Island). For both study sites different monitoring methods were used to obtain some population parameters. Site occupancy models of MacKenzie et al. (2002) gave reliable site-specific estimations of occupancy and detection probability using covariate information and presence-absence data collected from 50 sites in the Waitakere Ranges and four repeated visits during 2008. Elevation and distance searched were found to have an important effect on occupancy levels, while time taken to search the site was important variable determining detection probabilities. Also, parameters were estimated for three age classes separately. Statistical models were used to infer abundance from occupancy analysis, and results were compared with the distribution of relative abundances obtained from repeated transect counts and an established sight/re-sight criterion. In addition, the use of surrogate measures for relative abundance was explored. Detection probability and the distance to first frog found were found to have a significant correlation with relative abundance. These measures can be used to infer relative abundance in future site occupancy surveys. Two surveys and a pilot site occupancy survey were conducted on Great Barrier Island, and presence of frogs was confirmed atthe northern block, and in a small seepage in the central block. No new locations were found. Waitakere Ranges and Great Barrier Is. populations were tested for the presence of chytridiomycosis, and all frogs sampled tested negative (n = 124) which means that if present chytridiomycosis prevalence is lower than 5% with a 95% confidence interval. This and previous evidence suggests that L. hochstetteri may be resistant or immune to the disease. However, to confirm this additional studies are needed.

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16

Page, Girija. "An environmentally-based systems approach to sustainability analyses of organic fruit production systems in New Zealand : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Sustainable Agricultural Systems at Massey University, Palmerston North, New Zealand." Massey University, 2009. http://hdl.handle.net/10179/825.

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An environmentally-based systems approach to sustainability analyses of organic fruit production systems in New Zealand. This research introduces an approach for the assessment of the sustainability of farming systems. It is based on the premises that sustainability has an environmental bottom line and that there is very limited substitutability between natural capital and other forms of capital. Sustainability assessment is undertaken through analyses of energy and material flows of the system and their impacts on the environment. The proposed sustainability assessment approach is based on two high level criteria for sustainability: efficient use of energy and non-degradation of the environment from energy and material use. Sustainability assessment of organic orchard systems in New Zealand was undertaken to demonstrate this approach. Five indicators which address the two criteria for the sustainability of the orchard systems are the energy ratio, the CO2 ratio, changes in the soil carbon level, nutrient balances, and the leaching of nitrogen. Organic kiwifruit and organic apple systems are modelled based on their key energy and material flows and their interactions with the natural environment. The energy and material flows are converted into appropriate energy and matter equivalents based on coefficients taken from the published literature. Sustainability indicators are estimated over one growing season using two computer modelling tools, Overseer® and Stella®, in a life cycle approach. Sustainability assessment of the organic orchard systems suggests that the approach is useful for evaluating energy use and key environmental impacts that occur in soil, water and atmosphere. The results indicate that the model organic orchard systems are sustainable in terms of energy use and are a net sink of CO2-equivalent emissions. The implication of this result is that organic orchard systems potentially could trade carbon credits under the Kyoto Protocol. The findings also suggest that the sustainability assessment approach is capable of identifying the trade-offs within the sustainability indicators associated with particular management practices. Further research to improve and validate the proposed approach is essential, before it can be practically used for decision making at the orchard level and for policy making at the national level.

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17

Peacock, Lora. "Eco-climatic assessment of the potential establishment of exotic insects in New Zealand." Lincoln University, 2005. http://hdl.handle.net/10182/1530.

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To refine our knowledge and to adequately test hypotheses concerning theoretical and applied aspects of invasion biology, successful and unsuccessful invaders should be compared. This study investigated insect establishment patterns by comparing the climatic preferences and biological attributes of two groups of polyphagous insect species that are constantly intercepted at New Zealand's border. One group of species is established in New Zealand (n = 15), the other group comprised species that are not established (n = 21). In the present study the two groups were considered to represent successful and unsuccessful invaders. To provide background for interpretation of results of the comparative analysis, global areas that are climatically analogous to sites in New Zealand were identified by an eco-climatic assessment model, CLIMEX, to determine possible sources of insect pest invasion. It was found that south east Australia is one of the regions that are climatically very similar to New Zealand. Furthermore, New Zealand shares 90% of its insect pest species with that region. South east Australia has close trade and tourism links with New Zealand and because of its proximity a new incursion in that analogous climate should alert biosecurity authorities in New Zealand. Other regions in western Europe and the east coast of the United States are also climatically similar and share a high proportion of pest species with New Zealand. Principal component analysis was used to investigate patterns in insect global distributions of the two groups of species in relation to climate. Climate variables were reduced to temperature and moisture based principal components defining four climate regions, that were identified in the present study as, warm/dry, warm/wet, cool/dry and cool/moist. Most of the insect species established in New Zealand had a wide distribution in all four climate regions defined by the principal components and their global distributions overlapped into the cool/moist, temperate climate where all the New Zealand sites belong. The insect species that have not established in New Zealand had narrow distributions within the warm/wet, tropical climates. Discriminant analysis was then used to identify which climate variables best discriminate between species presence/absence at a site in relation to climate. The discriminant analysis classified the presence and absence of most insect species significantly better than chance. Late spring and early summer temperatures correctly classified a high proportion of sites where many insect species were present. Soil moisture and winter rainfall were less effective discriminating the presence of the insect species studied here. Biological attributes were compared between the two groups of species. It was found that the species established in New Zealand had a significantly wider host plant range than species that have not established. The lower developmental threshold temperature was on average, 4°C lower for established species compared with non-established species. These data suggest that species that establish well in New Zealand have a wide host range and can tolerate lower temperatures compared with those that have not established. No firm conclusions could be drawn about the importance of propagule pressure, body size, fecundity or phylogeny for successful establishment because data availability constrained sample sizes and the data were highly variable. The predictive capacity of a new tool that has potential for eco-climatic assessment, the artificial neural network (ANN), was compared with other well used models. Using climate variables as predictors, artificial neural network predictions were compared with binary logistic regression and CLIMEX. Using bootstrapping, artificial neural networks predicted insect presence and absence significantly better than the binary logistic regression model. When model prediction success was assessed by the kappa statistic there were also significant differences in prediction performance between the two groups of study insects. For established species, the models were able to provide predictions that were in moderate agreement with the observed data. For non-established species, model predictions were on average only slightly better than chance. The predictions of CLIMEX and artificial neural networks when given novel data, were difficult to compare because both models have different theoretical bases and different climate databases. However, it is clear that both models have potential to give insights into invasive species distributions. Finally the results of the studies in this thesis were drawn together to provide a framework for a prototype pest risk assessment decision support system. Future research is needed to refine the analyses and models that are the components of this system.

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18

Donaldson, Laura Patricia Constance. "The distribution of fatty acids and presence of environmental contaminants in the blubber of the New Zealand sea lion (Phocarctos hookeri) : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Conservation Biology at Massey University, Palmerston North, New Zealand." Massey University, 2008. http://hdl.handle.net/10179/887.

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The conservation of marine mammals relies on the knowledge of species ecology in order to assess the impacts of anthropogenic activites and make appropriate species management decisions. Blubber biopsies are a relatively non-invasive sampling protocol to provide ecological information; two particular uses are for dietary analysis via fatty acid signature analysis (FASA) and investigating the uptake of organochlorine (OC) and polychlorinated biphenyl (PCB) environmental contaminants. Blubber composition and structure may vary according to body site and depth due to its dynamic functioning. This may result in the vertical stratification and heterogenous distribution of blubber FAs, OCs and PCBs between body sites, giving variable interpretations of diet and contaminant levels depending on biopsy sample site and depth. The aim of this thesis is to determine the FA distribution of blubber from two body sample sites (dorsal pelvic and ventral thoracic) currently used for FASA of the New Zealand sea lion, Phocarctos hookeri (NZSL) and to determine the level of OCs and PCBs in the blubber of healthy NZSLs for comparison to diseased NZSLs recorded in the 1997/98 epidemic. Blubber samples were collected from 29 by-caught NZSLs incidentally captured by the squid fishery around the Auckland Islands (50º42’S, 166º5’E) during the years 2005 to 2007 (not all NZSLs were able to be analysed for each chapter). Full blubber cores from both sample sites were collected from 18 NZSLs. Both sites showed a relative homogeneity of FA profiles, indicating the similar deposition and mobilisation of FAs at the two sample sites. To determine if FA stratification occurred, full blubber cores from both sample sites of 20 NZSLs were divided into inner and outer halves. Both sites displayed the same pattern of vertical stratification or biochemical layering of FAs between the two divisions, indicating that stratification of FAs occurs in the blubber of the NZSL. A range of OCs and PCBs were then determined in full thoracic blubber cores of seven NZSLs. The levels were higher than those previously recorded in NZSLs affected by disease during a 1997/98 epidemic. The SPCB in NZSLs was 0.034-0.192 mg/kg lipids, below the suggested threshold of 17 mg/kg for adverse health affects in marine mammals. From the results of this study I can support current blubber biopsy sampling techniques for FASA in NZSL. Obtaining full blubber cores from either the thoracic or pelvic sample site will give a comparable interpretation of diet. The low levels of blubber OCs and PCBs suggest a minor role of contaminants acting as a possible causative agent toward disease outbreaks in the NZSL. This research provides important information for developing correct and consistent blubber sampling techniques for NZSL and other pinniped species. This will ensure more accurate interpretations of ecological information obtained from blubber biopsies and therefore improved species management and conservation decisions that may be based on such research.

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19

Pratt, Caroline. "Factors affecting the establishment, growth and survival of native woody plant communities on the Canterbury Plain, New Zealand." Lincoln University, 1999. http://hdl.handle.net/10182/1113.

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The native plant communities of Canterbury, South Island, New Zealand have been severely modified and degraded and the Canterbury Plain (750,000 ha) retains few remnants of its original forest and other ecosystems. The research presented here considers the mutualistic roles of exotic and indigenous species in the process of restoring degraded landscapes. Exotic species may have an important role in the (re) establishment of desired indigenous species, and may influence succession through to a forest dominated by them. One aspect of this work describes indigenous plant community regeneration facilitated by exotic willow (Salix spp.) woodland on the Canterbury Plain. Natural colonisation of the willow woodland by native plants was investigated, with respect to variation in the physical environment in the willow stand. Key factors in the success of willow woodland as a nursery for regeneration of native vegetation include: distance to the nearest seed source, the ability to attract seed dispersers (recruitment only occurred under perch sites), flooding potential (higher recruitment in areas less likely to flood) and possibly light availability. Control of vertebrate (and invertebrate) herbivory is also necessary for successful restoration. A second aspect was a field experiment in open pasture and in a non-native remnant woodland which was then used to investigate the effects of shelter, plant spacing, mulching and fertiliser on growth and survival of planted native woody species. With minimal management, the selected mid-late successional plants established poorly in the open pasture and had low survival rates (e.g.,Dacrycarpus dacrydioides, Pseudopanax arboreus, Aristotelia serrata, Melicytus ramiflorus). Only narrow-leaved species (e.g., Plagianthus reg ius, Hoheria angustifolia, Hebe salicifolia, Cordyline australis) survived this open pasture planting. In contrast, most species (broad and narrow-leaved) established under the sheltered sites. Exotic nursery vegetation and the establishment of native species, which will, in time, act as a seed source, will be important in successfully restoring a sustainable indigenous element in the cultural landscape of Canterbury. Ecological restoration requires an integrated approach, identifying and understanding the component processes of regeneration, and of the particular aspects/characteristics of the sites involved. This research shows that naturally established plants where existing shelter is available (in this case established willows) tend to have higher growth rates than individually planted plants in open situations, and that the availability of a suitable seed source can also contribute to successful establishment and growth rates. The meeting of restoration targets on the Canterbury Plain may be accelerated, and costs reduced, through the utilisation of areas where exotic species occur (for instance, extensive willow stands in riparian areas adjacent to waterways) and more particularly, where a local seed source is also available. The findings of this research can contribute to restoration management in helping identify the best practices, based on research, that can lead to the restoration of original plant and animal communities.

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20

Chakraborty, Manas. "Spatial pattern in macroinvertebrate communities in headwater streams of New Zealand and a multivariate river classification system : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Ecology at Massey University, Palmerston North, New Zealand." Massey University, 2008. http://hdl.handle.net/10179/1067.

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Macroinvertebrate data collected from 120 headwater streams in New Zealand were used to test the ability of the Freshwater Environments of New Zealand River Classification (FWENZ) to explain spatial variation in unimpacted stream invertebrate communities. FWENZ is a GIS based multivariate river environment classification of the sections of national river network. The classification performance of the FWENZ was examined to determine the optimum classification level which could be used for the purpose of conservation and biomonitoring of New Zealand rivers and streams. The classification performance of the FWENZ was also compared to those of two other river classification systems, the ecoregions and the River Environment Classification (REC). Results of the analysis of similarity (ANOSIM) test showed that discrimination of the study sites based on interclass differences in macroinvertebrate community composition was optimal at FWENZ 100 class level which classifies the New Zealand rivers and streams into 100 different groups. The FWENZ 100 class level distinguished the biological variation of the study sites at a finer spatial scale than the REC Geology level. Although performance of the ecoregions classification was stronger than both the river environmental classifications, the REC and the FWENZ, but it was unable to explain the variation in local assemblage structures. Multivariate analyses of the macroinvertebrate abundance data and the associated environmental variables at three different spatial scales (upstream catchment, segment, and reach) were used to identify environmental predictors of assemblage patterns. Catchmentscale measures of climatic, topographic and landcover factors were more strongly correlated with macroinvertebrate community structures than segment scale measures, whereas reachscale measures of instream physicochemical factors and riparian characteristics had the least association with assemblage patterns. Despite the strong influences of cathment-scale factors on macroinvertebrate communities, local factors like water temperature, stream velocity, reach elevation, percent canopy cover and percent moss cover were also involved in explaining the within-region variation in assemblage patterns, which indicates the importance of considering regional as well as local factors as surrogates of stream invertebrate communities to provide a base for stream bioassessment programmes at multiple scales.

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21

Chng, Soon Fang. "Microbial factors associated with the natural suppression of take-all in wheat in New Zealand : a thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy at Lincoln University, Canterbury, New Zealand /." Diss., Lincoln University, 2009. http://hdl.handle.net/10182/863.

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Take-all, caused by the soilborne fungus, Gaeumannomyces graminis var. tritici (Ggt), is an important root disease of wheat that can be reduced by take-all decline (TAD) in successive wheat crops, due to general and/or specific suppression. A study of 112 New Zealand wheat soils in 2003 had shown that Ggt DNA concentrations (analysed using real-time PCR) increased with successive years of wheat crops (1-3 y) and generally reflected take-all severity in subsequent crops. However, some wheat soils with high Ggt DNA concentrations had low take-all, suggesting presence of TAD. This study investigated 26 such soils for presence of TAD and possible suppressive mechanisms, and characterised the microorganisms from wheat roots and rhizosphere using polymerase chain reaction (PCR) and denaturing gradient gel electrophoresis (DGGE). A preliminary pot trial of 29 soils (including three from ryegrass fields) amended with 12.5% w/w Ggt inoculum, screened their suppressiveness against take-all in a growth chamber. Results indicated that the inoculum level was too high to detect the differences between soils and that the environmental conditions used were unsuitable. Comparison between the Ggt DNA concentrations of the same soils collected in 2003 and in 2004 (collected for the pot trial), showed that most soils cropped with 2, 3 and 4 y of successive wheat had reduced Ggt DNA concentrations (by 195-2911 pg g-1 soil), and their disease incidences revealed 11 of the 29 test soils with potential take-all suppressiveness. Further pot trials improved the protocols, such that they were able to differentiate the magnitudes of suppressiveness among the soils. The first of the subsequent trials, using 4% w/w Ggt inoculum level, controlled conditions at 16°C, 80% RH with alternate 12 h light/dark conditions, and watering the plants twice weekly to field capacity (FC), screened 13 soils for their suppressiveness against take-all. The 13 soils consisted of 11 from the preliminary trial, one wheat soil that had been cropped with 9 y of wheat (considered likely to be suppressive), and a conducive ryegrass soil. The results revealed that 10 of these soils were suppressive to take-all. However, in only four of them were the effects related to high levels of microbial/biological involvement in the suppression, which were assessed in an experiment that first sterilised the soils. In a repeat trial using five of the soils H1, H3, M2, P7 (previously cropped with 3, 3, 4 and 9 y successive wheat, respectively) and H15 (previously cropped with 5 y of ryegrass), three of them (H1, H3 and M2) had reduced Ggt DNA concentrations (>1000 pg g-1 soil reductions), and were confirmed to be suppressive to take-all. A pot trial, in which 1% of each soil was transferred into a γ-irradiated base soil amended with 0.1% Ggt inoculum, indicated that soils H1 and H3 (3 y wheat) were specific in their suppressiveness, and M2 (4 y wheat) was general in its suppressiveness. The microbial communities within the rhizosphere and roots of plants grown in the soils, which demonstrated conduciveness, specific or general suppressiveness to take-all, were characterised using PCR-DGGE, and identities of the distinguishing microorganisms (which differentiated the soils) identified by sequence analysis. Results showed similar clusters of microorganisms associated with conducive and suppressive soils, both for specific and general suppression. Further excision, re-amplification, cloning and sequencing of the distinguishing bands showed that some actinomycetes (Streptomyces bingchengensis, Terrabacter sp. and Nocardioides sp.), ascomycetes (Fusarium lateritium and Microdochium bolleyi) and an unidentified fungus, were associated with the suppressive soils (specific and general). Others, such as the proteobacteria (Pseudomonas putida and P. fluorescens), an actinomycete (Nocardioides oleivorans), ascomycete (Gibberella zeae), and basidiomycete (Penicillium allii), were unique in the specific suppressiveness. This indicated commonality of some microorganisms in the take-all suppressive soils, with a selected distinguishing group responsible for specific suppressiveness. General suppressiveness was considered to be due to no specific microorganisms, as seen in soil M2. An attempt to induce TAD by growing successive wheat crops in pots of Ggt-infested soils was unsuccessful with no TAD effects shown, possibly due to variable Ggt DNA concentrations in the soils and addition of nutrients during the experiment. Increasing numbers of Pseudomonas fluorescens CFU in the rhizosphere of plants, during successive wheat crops was independent of the Ggt DNA concentrations and disease incidence, suggesting that increases in P. fluorescens numbers were associated with wheat monoculture. This study has demonstrated that TAD in New Zealand was due to both specific and general suppressiveness, and has identified the distinguishing microorganisms associated with the suppression. Since most of these distinguishing microorganisms are known to show antagonistic activities against Ggt or other soilborne pathogens, they are likely to act as antagonists of Ggt in the field. Future work should focus on validating their effects either individually, or interactively, on Ggt in plate and pot assays and under field conditions.

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22

Berndt, Lisa A. "The effect of floral resources on the leafroller (Lepidoptera: Tortricidae) parasitoid Dolichogenidea tasmanica (Cameron)(Hymenoptera: Braconidae) in selected New Zealand vineyards." Lincoln University, 2002. http://hdl.handle.net/10182/1045.

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In this study, buckwheat (Fagopyrum esculentum Moench) and alyssum (Lobularia maritima (L.)) flowers were used to examine the effect of floral resources on the efficacy of the leafroller parasitoid Dolichogenidea tasmanica (Cameron) in vineyards. This was done by assessing the influence of these flowers on parasitoid abundance and parasitism rate, and by investigating the consequences of this for leafroller abundance. In laboratory experiments, alyssum flowers were used to investigate the effect of floral food on the longevity, fecundity and sex ratio of D. tasmanica. Dolichogenidea tasmanica comprised more than 95 % of parasitoids reared from field collected leafrollers in this study. The abundance of D. tasmanica during the 1999-2000 growing season was very low compared with previous studies, possibly due to the very low abundance of its leafroller hosts during the experiment. The number of males of this species on yellow sticky traps was increased (although not significantly) when buckwheat flowers were planted in a Marlborough vineyard; however, the number of female D. tasmanica on traps was no greater with flowers than without. The abundance of another leafroller parasitoid, Glyptapanteles demeter (Wilkinson)(Hymenoptera: Braconidae), on traps was also not significantly affected by the presence of buckwheat flowers, although females of this species were caught in greater numbers in the control than in buckwheat plots. Naturally-occurring leafrollers were collected from three vineyard sites in Marlborough, and one in Canterbury during the 2000-2001 season to assess the effect of buckwheat and alyssum flowers on parasitism rate. Parasitism rate more than doubled in the presence of buckwheat at one of the Marlborough vineyards, but alyssum had no effect on parasitism rate in Canterbury. A leafroller release/recover method, used when naturally-occurring leafrollers were too scarce to collect, was unable to detect any effect of buckwheat or alyssum on parasitism rate. Mean parasitism rates of approximately 20 % were common in Marlborough, although rates ranged from 0 % to 45 % across the three vineyard sites in that region. In Canterbury in April, mean parasitism rates were approximately 40 % (Chapter 4). Rates were higher on upper canopy leaves (40-60 %) compared with lower canopy leaves and bunches (0-25 %). Leafroller abundance was apparently not affected by the presence of buckwheat in Marlborough, or alyssum in Canterbury. Buckwheat did, however, significantly reduce the amount of leafroller evidence (webbed leafroller feeding sites on leaves or in bunches) in Marlborough, suggesting that the presence of these flowers may reduce leafroller populations. Leafrollers infested less than 0.1 % of Cabernet Sauvignon leaves throughout the 1999-2000 growing season, but increased in abundance in bunches to infest a maximum of 0.5 % of bunches in late March in Marlborough. In Pinot Noir vines in the 2000-2001 season, leafroller abundance was also low, although sampling was not conducted late in the season when abundance reaches a peak. In Riesling vines in Canterbury, between 1.5 % and 2.5 % of bunches were infested with leafrollers in April. In the laboratory, alyssum flowers significantly increased the longevity and lifetime fecundity of D. tasmanica compared with a no-flower treatment. However, daily fecundity was not increased by the availability of food, suggesting that the greater lifetime fecundity was related to increases in longevity. Parasitoids were also able to obtain nutrients from whitefly honeydew, which resulted in similar longevity and daily fecundity to those when alyssum flowers were present. The availability of food had a significant effect on the offspring sex ratio of D. tasmanica. Parasitoids reared from naturally-occurring leafrollers produced an equal sex ratio, assumed to be the evolutionarily stable strategy (ESS) for this species. In the laboratory, this ESS was observed only when parasitoids had access to alyssum flowers. Without food, or with honeydew only, sex ratios were strongly male-biased. In the field, floral resources affected the sex ratio of D. tasmanica only when this species was reared from leafrollers released and recovered in Marlborough. In that experiment, buckwheat shifted the sex ratio in favour of female production from the equal sex ratio found in control plots. No firm explanations can be given to account for these results, due to a lack of research in this area. Possible mechanisms for the changes in sex ratio with flowers are discussed. This study demonstrated that flowers are an important source of nutrients for D. tasmanica, influencing the longevity, fecundity and offspring sex ratio of this species. However, only some of the field experiments were able to show any positive effect of the provision of floral resources on parasitoid abundance or parasitism rate. More information is needed on the role these parasitoids, and other natural enemies, play in regulating leafroller populations in New Zealand vineyards, and on how they use floral resources in the field, before recommendations can be made regarding the adoption of this technology by growers.

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23

Kautoke-Holani, Alisi Wenonalita. "Agricultural export growth and economic development for Tonga : the quest for efficiency : a thesis presented in partial fulfilment of the requirements for the degree of Master of Public Policy at Massey University, Albany, New Zealand." Massey University, 2008. http://hdl.handle.net/10179/899.

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Neo-liberalism has become the dominant approach to economic development since the 1980s. Based on the economic principle of “efficiency”, the Washington Consensus and its supporters have avidly promoted the neoliberal orthodoxy as the ideal blueprint for the economic development of all countries in every region. However, as this thesis has discovered, the efficiency of public policy is weighed not by its conformity to an ideology but on how effective it responds to the economic and social problems of the population in question. In recent years Tonga has endured severe economic shocks which have pushed its low growth economy to the brink of economic crisis. In response to this crisis, the Government has chosen greater economic liberalisation and private sector – led growth to lead the economy to recovery. The Washington Consensus and its international supporters claim that this is the best policy response for Tonga due to the belief that greater liberalisation leads to greater efficiency. This thesis however believes that at the current dire state of the economy, it is not enough for Tongan public policy to just conform to international views on efficient economic development but to ensure that its economic development policies address the economic and social needs of the general Tongan population. With this in mind, this thesis investigated the role of agriculture in economic development. It identified that for an agriculture-based country such as Tonga, at low levels of growth, agricultural development is fundamental to long term economic growth. This research also revealed that agricultural growth is maximised through trade hence suggesting increased focus on agricultural export development. Based on these findings, this research project set out to verify the efficiency of Government agricultural policies by identifying the views of agricultural exporters and comparing these with Government approaches to agricultural export development in Tonga.

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24

Dittmer, Keren Elizabeth. "Inherited rickets in Corriedale sheep : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy at Massey University, Palmerston North, New Zealand." Massey University, 2008. http://hdl.handle.net/10179/882.

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Inherited rickets of Corriedale sheep is a newly discovered skeletal disease of sheep with simple autosomal recessive inheritance. The clinical signs resemble rickets in other species and include decreased growth rate, thoracic lordosis and angular limb deformities. Radiographic features include physeal thickening, blurred metaphyseal trabeculae and thickened porous cortices. Computed tomography scanning of long bones reveals increased bone mineral content and cortical area, but decreased bone mineral density. Gross lesions include segmental thickening of physes, growth arrest lines, collapse of subchondral bone of the humeral head, thickened cortices and enthesophytes around distal limb joints. Microscopically there is persistence of hypertrophic chondrocytes at sites of endochondral ossification, inappropriate and excessive osteoclastic resorption, microfractures and wide, unmineralised osteoid seams lining trabeculae and filling secondary osteons. Affected sheep are persistently hypophosphataemic and hypocalcaemic. Normal serum 25-hydroxyvitamin D3 concentration accompanied by a two-fold elevation in 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) suggested a defect in endorgan responsiveness to vitamin D as a likely mechanism, but this was not supported by in vitro studies using cultured skin fibroblasts. These studies revealed normal vitamin D receptor function and the presence of 24- hydroxylase mRNA in cells from affected sheep, even without induction by 1,25(OH)2D3. Inappropriate overexpression of 25-hydroxyvitamin D3-24- hydroxylase, the enzyme that breaks down active vitamin D, is therefore considered the probable cause of inherited rickets in Corriedale sheep. Such a mechanism has not previously been described as a cause of inherited rickets in humans or other animal species. Treatment of affected sheep with high oral doses of vitamin D3 weekly for 3 months showed a trend towards increased bone mineral density, thus supporting an intact vitamin D receptor. Preliminary studies on immune function revealed reduced numbers of CD4+ and CD8+ lymphocytes and reduced interferon-? production by lymphocytes stimulated with parasite antigen. This new form of inherited rickets may be widespread in

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25

Newcombe, Vernon Claude. "Mercury use in the goldmining industry : a retrospective examination of elemental mercury use in the gold mining industry of the West Coast of New Zealand in the period 1984-1988 : a thesis submitted in partial fulfilment of the requirement for the degree of Master of Philosophy (Science) at Massey University, Wellington, New Zealand." Massey University, 2008. http://hdl.handle.net/10179/832.

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26

Gravuer, Kelly. "Determinants of the introduction, naturalisation, and spread of Trifolium species in New Zealand." Master's thesis, Lincoln University. Bio-Protection and Ecology Division, 2004. http://theses.lincoln.ac.nz/public/adt-NZLIU20071015.060329/.

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Two conceptual approaches which offer promise for improved understanding of biological invasions are conceptualizing the invasion process as a series of distinct stages and explicitly incorporating human actions into analyses. This study explores the utility of these approaches for understanding the invasion of Trifolium (true clover) species in New Zealand. From the published literature, I collected a range of Trifolium species attributes, including aspects of global transport and use by humans, opportunistic association with humans in New Zealand, native range attributes, habitat characteristics, and biological traits. I also searched historical records to estimate the extent to which each species had been planted in New Zealand, a search facilitated by the enormous importance of Trifolium in New Zealands pastoral agriculture system. Regression analysis and structural equation modelling were then used to relate these variables to success at each invasion stage. Fifty-four of the 228 species in the genus Trifolium were intentionally introduced to New Zealand. Species introduced for commercial agriculture were characterised by a large number of economic uses and presence in Britain, while species introduced for horticulture or experimental agriculture were characterised by a large native range area. Nine of these 54 intentionally introduced species subsequently naturalised in New Zealand. The species that successfully naturalised were those that had been planted extensively by humans and that were well-matched to the New Zealand climate. A further 16 species (from the pool of 174 species that were never intentionally introduced) arrived and naturalised in New Zealand without any recorded intentional aid of humans. Several attributes appeared to assist species in unintentional introduction-naturalisation, including a good match to the New Zealand climate, a large native range area, presence in human-influenced habitats, a widespread distribution in Britain, and self-pollination capability. The 25 total naturalised species varied greatly in their current distributions and in the rates at which they had spread to achieve those distributions. Species that had spread quickly and are currently more widespread had been frequent contaminants in the pasture seed supply and have a long flowering period in New Zealand. Other biological traits and native range attributes played supporting roles in the spread process. Attributes facilitating success clearly varied among invasion stages. Humans played a dominant role at all stages of this invasion, although biological traits had increasing importance as a species moved through the invasion sequence. My findings suggest that incorporation of human actions and the stage-based framework provide valuable insight into the invasion process. I discuss potential avenues by which these approaches might be integrated into predictive invasion models.

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Williams, Rachael M. "Do geographical indications promote sustainable rural development? : two UK case studies and implications for New Zealand rural development policy." Lincoln University, 2007. http://hdl.handle.net/10182/585.

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Geographical indications (GIs) are one form of protective labelling used to indicate the origin of food and alcohol products. The role of protected geographical indicators as a promising sustainable rural development tool is the basis for this research. The protection of geographical indications is a rather controversial subject and much research is still required for both sides of the debate. The research method employed for this study is qualitative critical social science. Two Case studies are used to investigate the benefits brought to rural areas through the protection of GIs. The case studies include the GIs Jersey Royal and Welsh Lamb both from the United Kingdom a member of the European Union (the EU is in favour of extended protection of GIs for all agro-food products under the 1994 WTO/TRIPS agreement on geographical indications). Twenty-five indepth interviews were conducted for this study the duration of the interviews was approximately one hour. The study identifies predominantly indirect links between GIs and sustainable rural development, through economic and social benefits bought to rural areas by the GIs investigated - less of a connection was found to ecological elements. No considerable cost for GI protection was discovered. This finding suggests that GIs are worthwhile for implementation in New Zealand as a rural development tool.

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Harper, Sharleen Anne. "Mathematical models for dispersal of aerosol droplets in an agricultural setting : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Mathematics at Massey University, Albany, New Zealand." Massey University, 2008. http://hdl.handle.net/10179/814.

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Agrichemical spray drift is an issue of concern for the orcharding industry. Shelterbelts surrounding orchard blocks can significantly reduce spray drift by intercepting droplets from the airflow. At present, there is little information available with which to predict drift deposits downwind, particularly in the case of a fully-sheltered orchard block. In this thesis, we develop a simple mathematical model for the transport of airborne drifting spray droplets, including the effects of droplet evaporation and interception by a shelterbelt. The object is for the model to capture the major features of the droplet transport, yet be simple enough to determine an analytic solution, so that the deposit on the ground may be easily calculated and the effect of parameter variations observed. We model the droplet transport using an advection-dispersion equation, with a trapping term added to represent the shelterbelt. In order to proceed analytically, we discretise the shelterbelt by dividing it into a three-dimensional array of blocks, with the trapping in each block concentrated to the point at its centre. First, we consider the more straightforward case where the droplets do not evaporate; solutions are presented in one, two and three dimensions, along with explicit expressions for the total amount trapped and the deposit on the ground. With evaporation, the model is more difficult to solve analytically, and the solutions obtained are nestled in integral equations which are evaluated numerically. In both cases, examples are presented to show the deposition profile on the ground downwind of the shelterbelt, and the corresponding reduction in deposit from the same scenario without the shelterbelt.

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29

Erceg, Vicki Heather. "Detection of behavioural and cognitive dysfunction in mucopolysaccharidosis IIIA affected dogs : a thesis presented in partial fulfilment of the requirements for the degree of Master of Veterinary Science at Massey University, Palmerston North, New Zealand." Massey University, 2009. http://hdl.handle.net/10179/1053.

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This study investigated whether behavioural and cognitive dysfunction caused by mucopolysaccharidosis (MPS) IIIA can be detected early in affected dogs’ lives, and to describe the behaviours of these dogs. No other scientific papers have been published on this topic and the population of dogs examined in this study are the only MPS IIIA affected dog colony available worldwide for study. Three main tests were performed on the population of MPS IIIA affected dogs. Physical behavioural assessment tests were performed at six and eight weeks of age and from twenty weeks of age a cognitive function task was taught and then tested to measure the dogs’ performance. A previously validated questionnaire, the canine behavioural assessment and research questionnaire (C-BARQ), was completed at three, six and twelve months of age. The researchers in these studies were blinded to the MPS IIIA status of the dogs examined. The behaviours shown by the MPS IIIA puppies at six and eight weeks of age were not significantly different from the behaviours of the unaffected puppies. This finding supported the research of other MPS IIIA studies and suggests that clinical behavioural changes do not occur at such a young age. The behaviours shown by the MPS IIIA affected puppies appeared to be normal puppy behaviours similar to those described in previous research on puppies. The C-BARQ measured the behaviours shown by the MPS IIIA affected and unaffected dogs. Most of the MPS IIIA affected dogs’ behaviours were not significantly different from the unaffected dogs’ behaviours, but MPS IIIA affected dogs did retrieve significantly more than unaffected dogs at three months of age, and were less distractible at twelve months of age. It would be worth investigating these findings further to decide whether it suggests a subtle alteration in brain functioning. The cognitive function test showed a significant decrease in the success of the MPS IIIA affected dogs in the final maze test. This is the first study on dogs affected with MPS IIIA to find a decline in cognitive function before the occurrence of cerebellar clinical signs and this new knowledge may lead to future developments measuring therapy response and disease progression. The T-shaped maze testing may be valuable in future research on cognitive function in dogs with other diseases such as epilepsy. Thus this thesis provides valuable information on canine MPS IIIA and provides a foundation for future disease investigations.

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30

Irvin, N. A. "Understorey management for the enhancement of populations of a leafroller (Lepidoptera: Tortricidae) parasitoid (Dolichogenidea tasmanica (Cameron)) in Canterbury, New Zealand apple orchards." Lincoln University, 1999. http://hdl.handle.net/10182/1111.

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This study investigated understorey management in Canterbury, New Zealand, apple orchards for the enhancement of populations of Dolichogenidea tasmanica (Cameron) (Braconidae) for leafroller (Lepidoptera: Tortricidae) biological control. The first objective was to determine the influence of understorey plants on the abundance of D. tasmanica and leafroller parasitism, and to investigate the mechanisms behind this influence. The second was to determine the most suitable understorey plants in terms of their ability to enhance parasitoid abundance, leafroller parasitism, parasitoid longevity, parasitoid fecundity and its ability to not benefit leafroller. Results from three consecutive field trials showed that buckwheat (Fagopyrum esculentum Moench), coriander (Coriandrum sativum L.), alyssum (Lobularia maritima (L.) Desv), and, to a lesser extent, broad bean (Vicia faba L.), enhanced parasitoid abundance and leafroller parasitism. The mechanisms behind the effects of understorey plants had previously been unexplored. However, results here showed that it was the flowers or the buckwheat that 'attracted' the parasitoid to the plant and not the shelter, aphids or microclimate that the plant may also provide. Providing flowering plants in the orchard understorey also increased immigration of parasitoids and enhanced parasitoids and enhanced parasitoid longevity and fecundity in the laboratory. In contrast, the understorey plants had no influence on the female:male ratio of D. tasmanica. Although coriander enhanced leafroller parasitism three-fold in field experiments compared with controls, it failed to enhance the longevity of both sexes of D. tasmanica in the laboratory compared with water-only. Broad bean significantly enhanced parasitoid abundance three-fold and significantly increased parasitism from 0% to 75% compared with the controls on one leafroller release date. However, laboratory trials showed that of male D. tasmancia but it did not enhance female longevity. Also, female D. tasmanica foraging on broad bean produced a total of only three parasitoid cocoons, but this result was based on an overall 6.5% survival of larvae to pupae or to parasitoid cocoon. Furthermore, results suggested that extrafloral nectar secretion decreased as the plants matured. Phacelia (Phacelia tanacetifolia Benth.) did not significantly enhance parasitism rate in the field compared with controls, and numbers of D. tasmanica captured by suction sampling were significantly lower in phacelia treatments compared with alyssum, buckwheat and control plots. Also, laboratory experiments showed that survival of D. tasmanica on phacelia flowers was equivalent to that on water-only and significantly lower than on buckwheat. These results suggest that phacelia does not provide nectar to D. tasmanica, only pollen, and therefore is not a suitable understorey plant for D. tasmanica enhancement in orchards. Buckwheat and alyssum showed the most potential as understorey plants for the enhancement of natural enemies. Buckwheat not only increased numbers of D. tasmanica seven-fold, but also increased numbers of beneficial lacewings (Micromus tasmaniae (Walker)) and hover flies (Syrphidae) captured on yellow sticky traps compared with the controls. It significantly increased leafroller parasitism by D. tasmanica from 0% to 86% compared with the controls (on one date only), and in the laboratory enhanced D. tasmanica longevity and increased fecundity compared with water-only. Similarly, alyssum significantly increased parasitism rate compared with controls, and two-fold more D. tasmanica were suction sampled in these plots compared with controls. It also enhanced longevity of both sexes of D. tasmanica compared with water, and showed the most favourable characteristics in terms of being of no benefit to leafrollers. This is because it was not preferred over apple by leafroller larvae and when they were forced to feed on it, it caused high mortality (94.3%) and low pupal weight (15 mg). Furthermore, alyssum did not enhance the number of fertile eggs produced by adult leafrollers compared with water only. However, further research is required to address the overall effect of buckwheat and alyssum on crop production and orchard management, including effects on fruit yield and quality, frost risk, disease incidence, soil quality, weeds and other pests. Also, research into the ability of these plants to survive in the orchard with little maintenance, and into the optimal sowing rates, would be useful. Sampling natural populations of leafroller within each treatment showed that damage from leafrollers and the number of leafroller larvae were respectively 20.3% and 29.3% lower in the flowering treatments compared with the controls. Furthermore, field trials showed up to a six-fold increase in leafroller pupae in controls compared with buckwheat and alyssum. This suggests that increasing leafroller parasitism rate from understorey management in orchards will translate into lower pest populations, although neither larval numbers/damage nor pupal numbers differed significantly between treatments. Trapping D. tasmanica at a gradient of distances showed that this parasitoid travels into rows adjacent to buckwheat plots, indicating that growers may be able to sow flowering plants in every second or third row of the orchard, and still enhance leafroller biocontrol while minimising the adverse effects of a cover crop. Sowing buckwheat and alyssum in orchard understoreys may enhance biological control of apple pests in organic apple production and reduce the number of insect growth regulators applied in IFP programmes. However, the challenge still remains to investigate whether conservation biological control can reduce leafroller populations below economic thresholds.

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31

Nugent, Graham. "The role of wild deer in the epidemiology and management of bovine tuberculosis in New Zealand." Phd thesis, Lincoln University. Bio-Protection and Ecology Division, 2005. http://theses.lincoln.ac.nz/public/adt-NZLIU20070212.130927/.

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The eco-epidemiology of bovine tuberculosis (Tb) in wild deer (mainly red deer Cervus elaphus) in New Zealand was investigated. Bovine Tb is caused by Mycobacterium bovis. Specific aims were to clarify the likely routes of infection in deer, and to determine the status of deer as hosts of Tb, the likely rates and routes of inter- and intra-species transmission between deer and other wildlife hosts, the role of deer in spreading Tb, and the likely utility of deer as sentinels of Tb presence in wildlife. As the possum (Trichosurus vulpecula) is the main wildlife host of Tb, the research also included some investigation of transmission routes in possums. Patterns of infection were measured in 994 deer killed between 1993 and 2003. Tb prevalence varied between areas (range 836%). Few deer had generalised infection, with 2168% of infected deer having no visible lesions, depending on the area. The retropharyngeal lymph nodes and oropharyngeal tonsils were commonly infected. No dependent fawns less than 0.75 years old were infected, indicating intra-species transmission is rare in wild deer. Where possums were not controlled, the net (cumulative) force of infection in young (14 y) deer was 0.100.24 per year in males and 0.090.12 per year in females, but much lower in older deer (less than 0.05 per year). Possum control reduced the net force of infection quickly, and eventually to zero. However, Tb persisted in possum-controlled areas through immigration of infected deer and, for almost a decade, through the survival of resident deer infected before possum control. Tb was lost from infected deer at an exponential rate of 0.13 per year, mostly as a result of deer recovering from infection rather than dying from it. Wild deer do die of Tb, but there was no discernible effect on age structure. The occurrence of infection in deer was not linked to the local deer or possum density at their kill sites (i.e. in their home range), but the area-wide prevalence of Tb in deer was closely correlated with Tb levels in possums, which were in turn correlated with area-wide measures of possum density. For wild deer in New Zealand, Tb is a persistent but usually inconsequential disease of the lymphatic system. It is acquired mainly by young independent deer, usually orally via the tonsils, and probably as a result of licking infected possums. Many species fed on deer carrion, including possums. Most possums encountering carrion did not feed on it, but a few fed for long periods. Other scavengers such ferrets (Mustela furo), hawks (Circus approximans), and weka (a hen-sized flightless native bird; Gallirallus australis) fed in a way that probably increased the infectivity of carrion to possums. Commercial deer hunting may have facilitated the historical establishment of Tb in possums. Scavenging (including cannibalism) and interactions with dead and dying possums are identified for the first time as potentially important routes for transmission of Tb to possums, and I develop new hypotheses involving peri- and post-mortem transmission in possums that explain many of the epidemiological patterns that are characteristic of the disease in possum. In continuous native forest, deer home range size averaged 250 hectares for six young females, and over twice that for two males. Over 90% of infected deer are likely to die within 2 km (females) or 6 km (males) of where they acquired Tb, but deer could occasionally carry Tb up to 30 km. Deer will be useful as sentinels, but only where other sentinels are rare, because the force of infection for a deer with a single infected possum in its home range is only 0.004 per year, compared to greater than 0.2 per year for deliberately released pigs. Deer are occasionally capable of initiating new cycles of infection in wildlife, but deer control is not essential to eradicate Tb from wildlife.

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32

Prattley, Deborah Jayne. "Risk-based suveillance in animal health : a thesis presented in partial fulfillment of the requirements for the degree of Doctor of Philosophy at Massey University, Palmerston North, New Zealand." Massey University, 2009. http://hdl.handle.net/10179/1011.

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Animal health surveillance is an important part of animal health care, particularly in countries dependent on livestock for food production and international trade. There are two major issues related to the provision of e®ective surveillance activities. Firstly, for good information to become available, the design and conduct of data collection activ- ities should be carried out following sound statistical principles. In reality, constraints such as imperfect tests and unavoidably-biased sampling strategies hinder straightfor- ward analysis and interpretation of survey results. Risk-based surveillance is used to target high-risk sub-populations to increase e±ciency of disease detection; however, biased datasets are generated. This thesis develops methodologies to design risk-based surveillance systems and al- low statistically valid analysis of the inherently biased data they generate. The ¯rst example describes the development of a method to analyse surveillance data gathered for bovine spongiform encephalopathy (BSE). The data are collected from four dif- ferent surveillance streams of animals tested for BSE, with each stream containing unavoidable biases and limitations. In the BSurvE model, these data are combined with demographic information for each birth cohort to estimate the proportion of each birth cohort infected with BSE. The prevalence of BSE in a national herd can then be estimated using the method of moments, whereby the observed number of infected animals is equated with the expected number. The upper 95% con¯dence limit for the prevalence is estimated both for infected countries and for those where no BSE has previously been detected. A similar approach to that used in BSurvE is then applied to surveillance data for trichinellosis, for which risk-based post-mortem testing is also performed. Negative results from multiple species using di®erent, imperfect tests are combined to give an estimate of the upper 95% con¯dence limit of the national prevalence of trichinellosis in a reference population. This method is used to provide support for freedom from trichinellosis in Great Britain. A di®erent approach to risk-based surveillance is explored as the surveillance strategy for detection of exotic causes of abortion in sheep and goats in New Zealand is examined. Using a geographic information system (GIS) maps of disease risk factors were overlain to produce a risk landscape for the lower North Island. This was used to demonstrate how areas of high- and low-risk of disease occurrence can be identi¯ed and used to guide the design of a risk-based surveillance programme. Secondly, within one surveillance objective there may be many ways in which the available funds or human resources could be distributed. This thesis develops a method to assess BSE surveillance programmes, and provides tools to facilitate BSE detection on the basis of infection risk and to increase the e±ciency of surveillance strategies. A novel approach to allocation of resources is developed, where portfolio theory con- cepts from ¯nance are applied to animal health surveillance. The example of surveil- lance for exotic causes of sheep and goat abortion is expanded upon. Risk of disease occurrence is assessed for a population over di®erent time periods and geographical areas within a country, and portfolio theory used to allocate the number of tests to be carried out within each of these boundaries. This method is shown to be more likely to detect disease in a population when compared to proportional allocation of the available resources. The studies presented here show new approaches that allow better utilisation of imperfect data and more e±cient use of available resources. They allow development of surveillance programmes containing an appropriate balance of scanning and targeted surveillance activities. Application of these methods will enhance the implementation and value of surveillance in animal health.

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33

Nalle, Catootjie Lusje. "Nutritional evaluation of grain legumes for poultry : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Poultry Nutrition at Massey University, Palmerston North, New Zealand." Massey University, 2009. http://hdl.handle.net/10179/1021.

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The nutritional value of faba beans (Vicia faba), Australian sweet lupins (Lupinus angustifolius), white lupins (Lupinus albus) and peas (Pisum sativum) grown in New Zealand for broilers were evaluated in terms of their nutritional characteristics, protein quality (protein efficiency ratio), apparent metabolisable energy, apparent ileal digestibility coefficient of amino acids and the effects on bird performance. The effects of dehulling and extrusion cooking on the nutritive value of legumes were also investigated. The first experiment discussed in Chapter 3 evaluated the effect of cultivars on the nutrient profile and protein quality of chickpeas (Cicer arietinum), Australian sweet lupins, peas and soybeans (Glycine max). With the exception of white lupins, cultivars had no effect on the proximate and fibre composition of grain legumes. Starch was the primary carbohydrate component of chickpeas and peas, whilst non-starch polysaccharides were the major carbohydrates in lupins. The legume proteins were deficient in lysine, methionine, cystine and threonine. No differences were found in protein quality between cultivars of the different grain legume species. The lowest weight gain and protein efficiency ratio, in addition to the highest relative pancreatic weight and mortality rate was found in raw soybeans, suggesting that soybeans contained high a concentration of anti-nutritional factors, such as protease inhibitors. Birds fed chickpeas, lupins and peas had a low mortality rate and relative pancreatic weight, confirming that the level of anti-nutrients in these legume seeds was low. The apparent metabolisable energy and apparent ileal digestibility coefficient of amino acids of faba beans, Australian sweet lupins, white lupins and peas were determined in the second experiment (Chapter 4). Cultivar effect on the apparent metabolisable energy values was observed only for faba beans and white lupins. Faba beans, white lupins and peas had comparable apparent metabolisable energy values, but these values were higher than those of Australian sweet lupins, and lower than that of soybean meal. No cultivar differences were found in the apparent ileal digestibility coefficient of amino acids of grain legumes. The apparent ileal digestibility coefficient of amino acids of both lupin species was found to be comparable to that of soybean meal. The effects of feeding diets containing 200 g/kg faba beans, lupins or peas on the performance, digestive tract development and litter quality of broilers were investigated in the third and fourth trials. In the cage trial (Chapter 5), the results showed that the weight gain of birds fed diets containing grain legumes was similar to that of control diet. Feed intake and feed per gain of birds fed diets containing the majority of grain legume cultivars did not differ from those fed the maize-soy diet. Birds fed diets containing faba beans had more dry and friable excreta compared to other treatment diets. The performance of birds fed diets containing 200 g/kg grain legumes during the 35 d grow-out period, in the floor pen trial (Chapter 6), confirmed the results of the cage trial. In this trial, weight gain and feed per gain of birds fed diets without meat meal were superior to those with meat meal. In cage trials, the modification of some segments of digestive tract development was probably due to the dietary NSP. Whilst in floor pen trial, digestive tract development was not influenced by the inclusion of grain legumes. The effect of methodology of determination (direct vs. difference method) on the apparent ileal digestibility coefficient of amino acids of wheat, maize, Australian sweet lupins, peas and soybean meal for broilers was evaluated in the fifth study (Chapter 7). The influence of methodology on apparent ileal digestibility coefficient of amino acids was found to vary amongst the feed ingredients. In general, the apparent ileal digestibility coefficient of amino acids of test ingredients determined by the difference method was higher than those determined by the direct method, suggesting that the use of the direct method may underestimate the apparent ileal digestibility coefficient of amino acids in low and medium protein ingredients. Data reported in Chapter 8 shows that dehulling increased the apparent metabolisable energy values of faba beans and Australian sweet lupins, but it had no beneficial effect on peas. The increase of apparent metabolisable energy values may be attributed to the decrease in non-starch polysaccharides of these legume seeds after dehulling. The removal of hulls increased the amino acid concentrations, but it had no effect on the apparent ileal digestibility coefficient of most amino acids. These results suggest that dehulling of grain legumes would be nutritionally beneficial and, likely to be economical in view of the improved amino acid concentrations and energy values. The final experiment (Chapter 9) demonstrated that extrusion of peas markedly influenced the content of crude protein, non-starch polysaccharides, starch, and trypsin inhibitors. The soluble non-starch polysaccharides and trypsin inhibitor contents of the majority of extruded pea samples were higher than those of raw peas, but insoluble and total non-starch polysaccharides decreased with extrusion. Extrusion had no effect on the apparent ileal protein digestibility and the apparent metabolisable energy of peas, but it increased ileal starch digestibility.

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34

Lin, Xiaoxiao. "Evaluation of Kahne rumen sensors in fistulated sheep and cattle under contrasting feeding conditions : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Agriculture at Massey University, Palmerston North, New Zealand." Massey University, 2009. http://hdl.handle.net/10179/1313.

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The Kahne rumen sensor (bolus) is a device developed to measure temperature, pressure and pH in non-fistulated animals. This bolus allows real-time monitoring of the rumen environment, which could help preventing health problems such as rumen acidosis in cows. It is less invasive to use boluses compared to other technologies that measure the ruminal pH (e.g. rumenocentesis). Kahne boluses and transceivers are commercially available in the market. Several studies on the relationships between data recorded by the bolus and actual data recorded by independent devices were conducted. The bolus temperature and pressure were compared with actual temperature and pressure under controlled conditions. The pH drift was studied by comparing the difference between bolus and direct measurement over time. The capture of the data was calculated for each bolus in various experiments to examine the factors affecting the data capture rate of the boluses. Animal to animal variation was studied using boluses in a group of cows fed and managed under uniform conditions. An animal experiment involving fistulated cows eating two different diets was performed using boluses to monitor the changes of ruminal pH. There was no apparent interruption to normal animal behaviour as a result of using boluses. Regression relationships between bolus measurements and actual data for both temperature and pressure were developed and used for calibration of bolus data. The pH drift was a problem, as the regression relation between the pH difference and the time for one bolus from one experiment could not represent this bolus on other experiment. The data capture rate on the hourly basis ranged from 0 to 100%, but was usually between 30 to 70%. The data capture rate was affected by many factors and further studies to identify these factors are needed. A study of animal to animal variation suggests that in a comparison of 2 treatments, a minimum 3 cows per group would be required to detect the standard deviation of 0.11 for a pH difference of 5% of the mean (approximately 0.35 pH units). Seventeen cows per group would be required to detect the standard deviation of 0.33 for the same difference. The boluses effectively monitored the ruminal pH change in cows easting two different diets and the profile of change of pH was successfully analysed. Feeding 7.6 kg baleage twice a day cause pH to decrease at 0.009 pH units per minute during feeding, while offering a similar quantity of grass and hay once a day resulted in a decrease of 0.0009 pH units per minute during feeding. The beginning of pH increase was about 1 hour following feeding and continuous during resting and rumination. The level of pH increase did not differ significantly for two diets.. The Kahne devices appear to have advantages compared to other technologies for the measurement of parameters of the rumen environment on a real-time basis. Boluses are especially good at intensively monitoring the temperature, pressure, and pH in the rumen. The major limitations of this technology to be used are the data capture rate and the pH drift. By improving the limitations found in the experiment, the Kahne rumen sensor could become very useful for both scientific research and under commercial conditions for monitoring animal health.

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35

Hill, Andrew Gordon. "An investigation of Leucocytozoon in the endangered yellow-eyed penguin (Megadyptes antipodes) : a thesis presented in partial fulfilment of the requirements for the degree of Master of Veterinary Science at Massey University, Turitea, Palmerston North, New Zealand." Massey University, 2008. http://hdl.handle.net/10179/1063.

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Yellow-eyed penguins have suffered major population declines and periodic mass mortality without an established cause. On Stewart Island a high incidence of regional chick mortality was associated with infection by a novel Leucocytozoon sp. The prevalence, structure and molecular characteristics of this leucocytozoon sp. were examined in the 2006-07 breeding season. In 2006-07, 100% of chicks (n=32) on the Anglem coast of Stewart Island died prior to fledging. Neonates showed poor growth and died acutely at approximately 10 days old. Clinical signs in older chicks up to 108 days included anaemia, loss of body condition, subcutaneous ecchymotic haemorrhages and sudden death. Infected adults on Stewart Island showed no clinical signs and were in good body condition, suggesting adequate food availability and a potential reservoir source of ongoing infections. A polymerase chain reaction (PCR) survey of blood samples from the South Island, Stewart and Codfish Island found Leucocytozoon infection exclusively on Stewart Island. The prevalence of Leucocytozoon infection in yellow-eyed penguin populations from each island ranged from 0-2.8% (South Island), to 0-21.25% (Codfish Island) and 51.6-97.9% (Stewart Island). The high prevalence on Stewart Island represented the infection of 100% of chicks and 83% of adult yellow-eyed penguins when tested by PCR. Sequencing of Leucocytozoon sp. DNA found similarities between infections in yellow-eyed penguin adults and chicks, but differences to Leucocytozoon sp. DNA obtained from Fiordland crested penguins. These findings support the suggestion of cross infection between adults and chicks, and indicate that endemic infection in yellow-eyed penguins is unrelated to that in Fiordland crested penguins. Examination by histology and electron microscopy showed tissue megaloschizonts and circulating round gametocytes. Megaloschizonts up to 440µm diameter showed an affinity for hepatic and splenic tissue and were observed releasing occasional intact cytomeres. Round gametocytes were observed within leucocytes in visceral sections, but not peripheral blood smears. The morphology of Leucocytozoon sp. in yellow-eyed penguins showed similarities to the pathogenic species L. simondi and L. sakharoffi but not L. tawaki. A successful treatment protocol for leucocytozoonosis has not been established, although treatment in a Fiordland crested penguin was able to suppress parasitaemia. The role of Leucocytozoon in yellow-eyed penguins as a cause of morbidity and mortality remains unclear. Further investigation into direct pathogenicity, and the interaction of concurrent disease and environmental influences is required. The findings of this thesis provide potential management recommendations and highlight areas requiring further investigation.

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36

Hedley, Carolyn B. "The development of proximal sensing methods for soil mapping and monitoring, and their application to precision irrigation : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Soil Science at Massey University, Palmerston North, New Zealand." Massey University, 2009. http://hdl.handle.net/10179/1217.

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The potential of proximal soil sensing methods for high resolution investigation of soils in the landscape has been investigated. This addresses the need for improved environmental monitoring and management of soils within their environs. On-the-go electromagnetic (EM) mapping has been used to map soils, providing a high resolution (< 10m) spatially defined soil apparent electrical conductivity (ECa) datalayer. Vis-NIR field spectroscopy has been trialled for in situ analysis of soil carbon, nitrogen and moisture. The portable spectroradiometer has been used at 6 sites in the Taupo-Rotorua region for rapid, field analysis of soil carbon (R2 calibration = 0.95, R2 prediction = 0.75,) soil nitrogen (R2 calibration = 0.95, R2 prediction = 0.86) and moisture (R2 calibration = 0.96, R2 prediction = 0.70) by collecting reflectance spectra from the flat surface of a soil core; and at one Manawatu site for soil moisture (R2 calibration = 0.79, R2 prediction = 0.71), where the reflectance spectra were collected directly from a freshly cut in situ soil surface. EM mapping and Vis-NIR field spectroscopy were used in combination to spatially characterize soil moisture patterns at the Manawatu site. Soil available water-holding capacity (AWC) of ECa-defined zones has been assessed at six irrigated production farming sites. Two methods (predicted AWC v ECa; estimated AWC v ECa) have been used to relate soil ECa to soil AWC to predict spatial AWC (R2 = 0.8 at 5 sites). Site-specific soil water balance models have been developed at all sites; and a wireless real-time soil moisture monitoring network has been trialled at two sites, to be used with the ECa-AWC prediction model for the development of daily soil water status maps, for variable rate irrigation (VRI) scheduling. This digital, spatially defined soil water status information is available for upload to a sprinkler system modified for variable rate application. The calculated water savings with VRI were 926% with equivalent energy savings and improved irrigation water use efficiency. Drainage and runoff were reduced by 055% during the period of irrigation, with the accompanying reduced risk of nitrogen leaching. The reduction in virtual water content of product has also been assessed for VRI and compared with uniform rate irrigation (URI) at three study sites. This study suggests that these proximal sensing methods provide a new improved way of monitoring and mapping soils. This facilitates soil inventory mapping, for example soil moisture and carbon mapping. In addition, these high resolution environmental monitoring and mapping techniques provide the information required for optimizing site-specific management of natural resources at the farm scale. On-the-go electromagnetic (EM) mapping has enabled a step change in the pedological investigation of New Zealand soils. Resulting soil ECa maps provide a tool for improving traditional soil map boundaries because they delineate soil zones primarily on a basis of soil texture and moisture in non-saline soils. In this study the maps have been used for site-specific irrigation management at the farm-scale, aiming to increase the energy efficiency of this land management operation. The study has developed a method for improved use of freshwaters by more accurate irrigation scheduling, based on high resolution characterization of spatial and temporal soil differences.

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37

van, Hooijdonk Benedict Michael. "The physiological basis of vigour control by apple rootstocks - an unresolved paradigm : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Plant Physiology at Massey University, Palmerston North, New Zealand." Massey University, 2009. http://hdl.handle.net/10179/1137.

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For millennia, scions have been grafted onto dwarfing apple rootstocks to reduce final tree size. However, it is unclear how scion architecture is first modified by the dwarfing apple rootstock, the time from grafting when this occurs and the endogenous hormonal signalling mechanisms that may cause the initial modifications in growth that then define the future architecture of the scion. In this study, the dwarfing (M.9) rootstock significantly decreased the mean total shoot length and node number of ‘Royal Gala’ apple scions by the end of the first year of growth from grafting when compared with rootstock(s) of greater vigour (MM.106, M.793 and a ‘Royal Gala’ rootstock control). Similarly, the auxin transport inhibitor 1-N-naphthylphthalamic acid (NPA) applied to the stem of vigorous rootstocks significantly decreased mean total shoot length and node number of the scion, and the architectural changes imposed were generally similar to those imposed by M.9. For example, both treatments decreased the mean length and node number of the primary shoot, reduced the formation of secondary axes on the primary shoot and caused a greater proportion of primary and secondary shoots (if present) to terminate growth early. Decreased formation of secondary axes imposed by both treatments was reversed by applying the cytokinin benzylaminopurine (BAP) repeatedly to the scion, whilst applications of gibberellins (GA4+7) reduced the proportion of primary and secondary shoots that terminated growth early, therefore increasing the final mean length and node number of these shoot types. Both M.9 and NPA also significantly decreased the final mean dry mass and length of the root system. Given these general similarities, it is proposed that the basipetal IAA signal is of central importance in rootstock-induced scion dwarfing, and that a shoot/root/shoot signalling mechanism may exist whereby the stem tissue of the M.9 rootstock decreases the basipetal transport of IAA to the root during summer, thereby decreasing root growth and the amount of rootproduced cytokinin and gibberellin transported to scion. Reduced amounts of cytokinin transported to the scion may decrease branching, whilst reduced amounts of gibberellins may decrease the duration for which a large proportion of primary and secondary shoots grow. Analysis of endogenous hormones for newly grafted composite ‘Royal Gala’ apple trees on rootstocks of different vigour provided some additional support for these ideas. It is recommended that future studies elucidate what unique properties of the M.9 bark act to restrict IAA transport, whilst it is concluded that gene(s) regulating rootstock-induced scion dwarfing are likely to control processes within the rootstock that modify the metabolism of IAA, its basipetal transport and the subsequent synthesis of root-produced vigour-inducing hormones including cytokinins and gibberellins.

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38

Williamson, Michelle Leigh. "Differential responses of tillers to floral induction in perennial ryegrass (Lolium perenne L.) : implications for perenniality : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Plant Biology at Massey University, Palmerston North, New Zealand." Massey University, 2008. http://hdl.handle.net/10179/842.

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Development of sustainable practices is an important goal in agriculture. One possibility involves the development of perennial cereal crops, but the mechanisms of perenniality first need to be understood. While in annual cereals flowering structures die following seed production, in perennial grasses, perenniality is achieved by maintaining at least one shoot in a vegetative state. There are two views on perennating tiller origin in perennial grasses: some authors suggest that all over-wintering tillers flower in spring and summer, leaving spring-initiated tillers to perennate, while others indicate that spring-initiated tillers are too immature to survive summer conditions, thereby implying that flowering must be prevented in some over-wintering tillers. An understanding of perenniality will therefore require an understanding of flowering control in these species. Temperate perennial grasses have dual induction requirements for flowering, where plants become competent to perceive inductive signals following vernalisation, and flowering is initiated by inductive photoperiods. Two hypotheses were formulated to test these models. The ‘environmental control hypothesis’ stated that all adequately vernalised perennial ryegrass tillers would flower on sufficient exposure to inductive photoperiods. Alternatively, the ‘spatial control hypothesis’ stated that in addition to the environmental mechanisms, a spatial control mechanism acts to regulate flowering. Two experiments were conducted to test these hypotheses. Perennial ryegrass and Italian (annual) ryegrass were induced to flower and differences between the annual and perennial habits at flowering time were observed. However neither hypothesis was proven. In the second experiment, flowering was studied in detail in individual tillers of perennial ryegrass. The eldest tiller flowered in all flowering plants. The second eldest tiller did not flower in 72% of plants with more than one reproductive tiller, while the third eldest tiller flowered in 94% of these plants. These data favour the spatial control hypothesis which suggests that a spatial regulatory mechanism might act to repress flowering in some competent perennial ryegrass tillers. These results were supported by studies of meristem morphology and by a preliminary gene expression study. Maintenance of older, established tillers in a vegetative state might allow the perennial plant a greater chance of survival during summer.

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39

Linden, Danitsja Stephanie van der. "Ewe size and nutrition during pregnancy : effects on metabolic and productive performance of the offspring : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Animal Science at Massey University, Turitea, Palmerston North, New Zealand." Massey University, 2010. http://hdl.handle.net/10179/1343.

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Exposure of the fetus to adverse conditions in utero may result in developmental adaptations that alter metabolism and postnatal growth of the offspring. This thesis investigated the effects of dam size and nutrition during pregnancy on growth, metabolic function and lactational and productive performance of the female offspring to two years of age. Four-hundred and fifty heavy (60.8 kg ± 0.18) and 450 light (42.5 kg ± 0.17) dams were randomly allocated to ad libitum or maintenance nutritional regimens from days 21 - 140 of pregnancy, under pastoral grazing conditions. From one week prior to lambing, all dams were fed ad libitum until weaning. After weaning, female progeny were managed and fed under pastoral conditions as one group. Maternal nutrition during pregnancy affected lamb growth to weaning, however, after weaning lamb growth was affected by dam size. Dam size had no effect on glucose metabolism, adrenal function or fat metabolism in 16-month-old female twin offspring. Dam nutrition during pregnancy had a minor effect on glucose metabolism and no effect on adrenal function or lipolysis, however, it did possibly affect gluconeogenesis and/or glycogenolysis, with increased glucose production in ewes born to maintenance-fed dams. Ewes born to dams fed maintenance showed greater milk production, lactose percentage, lactose and crude protein yield. Ewes born to heavy dams showed greater milk production and lactose yield. Dam size had no effect on reproductive performance of the female offspring. Being born to a larger dam showed no advantages over being born to smaller dams, for number of lambs born and weight of lambs at birth and weaning. ‘Grand’dam maintenance nutrition increased lamb birth and weaning weight and lamb growth rates of the ‘grand’offspring. Ewes born to maintenance-fed dams could have an advantage over ewes born to ad libitum-fed dams in physiological stressful situations in life as their liver may be able to supply more glucose to support their growing conceptus and milk production to increase the chances of survival of their offspring. These results indicate that it is possible to programme the offspring by feeding their dams differently during pregnancy under grazing conditions. With a better understanding of how offspring can be programmed through different maternal nutritional regimens, it may be possible to significantly increase the production potential of the New Zealand ewe population.

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40

Sandiford, Anna. "Palynology and tephrostratigraphy of Quaternary coverbed sequences of the Auckland area, New Zealand." 2001. http://hdl.handle.net/2292/2218.

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This thesis presents the results of detailed palynological and tephrostratigraphic investigations of five sites around the Auckland Isthmus, which collectively contain a fragmented record spanning approximately the last 1.2 million years. A range of additional methods were applied including, radiometric dating, palaeomagnetism, identification of other palynomorphs and fossil wood, and calculation of deposition rates. Study of two late Quaternary sites provided information on the Last Glacial Maximum (LGM) environment of the Auckland Isthmus. This suggested LGM forest was spatially restricted, dominated by beech forest with minor podocarp elements and contained within extensive shruband grassland. Late Quaternary sites were more easily studied than early to mid Quaternary sites because the depositional environment in which they were found provided greater palynological and tephrostratigraphic detail. Detailed published late Quaternary tephrostratigraphy also allowed for tight chronological control, accurate interpolation of ages of uncorrelated tephra and assessment of the accuracy of radiocarbon dates. Forty late Quaternary tephra layers were identified, adding to the record of eruptions sourced from the Auckland Volcanic Field, Taupo Volcanic Zone and Taranaki Volcano. Since c. 24 ka the frequency of Late quaternary tephraforming events of significant volume to be recorded in the sediments on the Auckland Isthmus is 1 every 600 years. Study of early to mid Quaternary sites was hampered by lack of published tephrostratigraphic records for correlation. Last appearance data for four extinct taxa were tentatively extended. Significant depositional hiatuses were noted; the period between c. 1.0 Ma and c. 44 ka was particularly unsatisfactorily recorded. Three key tephra markers and nine previously undocumented tephra layers were documented. Spatial variation and alternating vegetation structure characterised cooler and warmer environments of the early to mid quaternary record. Extensive high diversity conifer-angiosperm forest occurred during warmer periods while reduced diversity beech-dominated forest contained within extensive shrub/grassland characterised the cooler periods. Certain combinations of taxa occurred during glacial/stadial and interglacial/interstadial periods and an attempt was made to generalise these. It was apparent the extremes of the LGM were not reached during this time, and-that climate oscillated between cool and warm periods sometimes characterised by vegetation assemblages without modem analogue. Extensive depositional hiatuses at one site, deposition of extremely thick, reworked, homogenous marine silt at a second site, and dipping bedding planes at a third site suggest sea level variation and/or tectonism were influential in the Quaternary depositional history of the Auckland Isthmus. However, not enough evidence was present to quantify this.

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41

Murray, Robert Ian. "Variable rate application technology in the New Zealand aerial topdressing industry." 2007. http://hdl.handle.net/10179/1399.

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Greater use of technology to assist aerial application of fertiliser will be of benefit to the topdressing industry and farmers. Benefits arise through automating the fertiliser flow control system; reducing off target fertiliser application, and managing fertiliser inputs based on the potential outputs of the farmland; thus increasing the profitability of hill country farming systems. A case for technology assisted application is developed by investigating the field performance of conventional and enhanced flow control systems and the effect of variable rate application on hill country pasture production. A single particle model that predicts flight trajectory from the particle force balance based on the aircraft groundspeed, axial and tangential propeller wash, wind characteristics and particle properties including sphericity was developed. Model predictions were compared to predictions from AGDISP 8.15. Results and trends were similar. The single particle ballistics model described above was extended to predict the lateral distribution of fertiliser after release from an aircraft. To achieve this, two parameters are important, the transverse flow profile of material leaving the hopper gatebox and the sphericity of the particles. Techniques for measuring these parameters are described and experimental results are presented for superphosphate. These data were used in the model to predict the lateral distribution pattern from a Gippsland Aeronautics 200C for a known discharge mass, which was compared to a measured pattern from the same aircraft for the same discharge mass. Good agreement between the shapes of the two distributions was found. The transverse distribution model provides a practical tool for optimising the design of spreaders, or optimum particle characteristics for a given spreader. It has the ability to predict the distribution profile of any particle size distribution from each, or all, of the spreader ducts. Culmination of the single particle and transverse distribution models led to the development of a deposition footprint model that was capable of predicting field application within a 25 ha trial site. The deposition footprint model was embedded inside a geographical information system and comparisons were made between the actual and predicted deposition across a series of transect lines. Good agreement was found. Following this, a comparison of the predicted field performance between an automated and manual control system were made. Economic benefits for a single application of superphosphate were identified through using automated control, where 10% less fertiliser was applied outside of the application zone when compared to the manually operated system. This equated to a net benefit of NZD $2800 for a 1500 ha hill country farming system. The value of improving the performance of a topdressing aircraft, on an industry level, was also examined. Cost/benefit analysis between a manual and automated system revealed a benefit of NZD $111,700 yr-1 for a single topdressing aircraft using the automated system. The economic impact of Variable Rate Application Technology (VRAT) is examined, using Limestone Downs as an example. The spatially explicit decision tree modelling technique was used to predict the annual pasture production over the entire Limestone Downs property. The resulting decision tree classes tended to follow the farm's digital elevation model. A series of six different fertiliser application scenarios were developed for comparison to a base line scenario using conventional aerial application techniques. VRAT outperformed the fixed rate applications in terms of pasture production and fertiliser utilisation. Full variable rate application and a model optimised prescription map, produced the highest annual pasture yield. Variable rate techniques were predicted to increase annual production and the spatial variability of that production. An economic analysis of the six production scenarios was undertaken. Farm cash surplus was calculated for each scenario and clearly revealed the benefits of using variable rate application technology. VRAT was found to be the most efficient and highest returning application method per hectare. Additional costs and increased charge-out rates were likely to occur under VRAT; nevertheless, the analysis indicated that significant financial incentives were available to the farmer. A sensitivity analysis revealed that even with a 20% increase in charge-out rate associated with VRAT, the farm's annual cash position varied by only $4500 (0.4%), suggesting the cost of implementing such a system is not prohibitive and would allow aircraft operators to add value to their services.

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42

Gillies, Craig. "Aspects of the ecology and management of small mammalian predators in northern New Zealand." 1998. http://hdl.handle.net/2292/1942.

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Each chapter in this thesis has been written as a separate paper intended for later publication. Rather than write one summary, an abstract for each chapter has been given in the order they are presented in the thesis. Chapter I. The prey species of domestic cats (Felis catus) in two suburbs of Auckland city, New Zealand. The prey brought in by 80 cats (Felis catus), over a year was monitored in two suburbs of Auckland New Zealand. The survey technique followed that of Churcher & Lawton (1987) where cat owners were asked to record (and if possible keep) the prey their cats brought in. The results for the year indicated that there were distinct differences in the type of prey taken by cats in each area. Rodents were the most important prey brought in by domestic cats in an urban / forest fringe habitat and invertebrates were the main prey brought in by domestic cats in a fully urban habitat. Birds and lizards were the second and third most important prey groups in both study areas. Rat and mouse snap trap indexes which were run at each study location, did not detect rodents in the urban habitat. The results from the urban/forest fringe concurred more with studies of feral cat diet in New Zealand whilst those from the urban area compared more to studies of domestic and stray cat diet in urban areas overseas. There were seasonal trends in the prey captured in each area and in both areas cats hunted less over the winter months. Chapter II. Diets of coexisting alien mammalian carnivores in Northern New Zealand. 120 feral cats, 85 stoats (Mustela erminea), 28 weasels (M. nivalis) and 16 ferrets (M. furo) were caught over three years, in Northland, New Zealand. The gut contents of these animals were examined and their food habits described. The main prey groups of cats were (in order of importance by weight), lagomorphs, rodents (Rattus spp & Mus musculus), other mammals, birds and invertebrates. The main prey of stoats were rodents, birds, lagomorphs, skinks (Cyclodina spp) and invertebrates. Skinks, followed by mice, were the main prey of weasels. Rabbits (Oryctolagus cuniculus) were the most commonly occurring prey item in the ferret guts. The food habits for cats and stoats were compared between different habitats within the Northland region where these animals were collected from. There was little difference between habitats, but invertebrates occurred more frequently and lagomorphs less frequently in the diet of animals from forest habitats compared to those from forest / pasture and coastal habitats. No differences were found in the prey of male and female cats, but invertebrates occurred more frequently in the guts of sub-adult cats compared to adult cats. Skinks occurred more frequently in the guts of female stoats, which tended to take smaller prey items than males. Chapter III. Home range of introduced mammalian carnivores, feral cats (Felis catus), stoats (Mustela erminea) and a ferret (M. furo) at Trounson Kauri Park, Northland, New Zealand. The minimum home ranges of eleven feral cats, four stoats and one male ferret were examined by radio telemetry at Trounson Kauri Park in Northland New Zealand. The average minimum home range of male feral cats was 305 ± 74ha. This was not significantly larger than the 122 ± 35 ha minimum average home range of female cats. The minimum average home range of three male stoats was 108 ± 19 ha and the minimum home range of one female stoat was 50 ha. The male ferret had a minimum home range of 179 ha. There was no overlap spatially, in the home range of three adult male cats. There was also very little spatial overlap in the home range of four female cats. There was substantial home range overlap with four sub-adult male cats. The home ranges of these sub-adult male cats also overlapped spatially with those of the adjacent females and adult males. The home ranges of two male stoats overlapped spatially to some degree and the home range of another male stoat overlapped that of the female stoat substantially. The home range of the male ferret overlapped the home ranges of all of the cats occupying similar areas of the park. The home ranges of two male stoats overlapped the home ranges of the adjacent cats but not into the "core" areas of those cats ranges. Chapter IV. Secondary poisoning of introduced mammalian carnivores during possum and rodent control operations at Trounson Kauri Park, Northland New Zealand. Predatory mammals were monitored by radio telemetry through a 1080 then brodifacoum poison baiting operation at Trounson Kauri Park in Northland, New Zealand to target possums (Trichosurus vulpecula) and rodents (Rattus rattus, Rattus norvegicus & Mus musculus). All six feral cats (Felis catus), and the single stoat (Mustela erminea) and ferret (Mustela furo) being monitored at the beginning of the operation died of secondary poisoning following the 1080 operation. A further two cats and four stoats were radio tagged and monitored through the ongoing poisoning campaign using brodifacoum in a continuous baiting regime. None of these radio tagged carnivores died of secondary poisoning. However, tissue analysis of additional carnivores trapped at Trounson found that cats, weasels (Mustela nivalis) and to a lesser extent stoats did contain brodifacoum residues. The duration that the radio tagged predators were alive in and around Trounson Kauri Park suggested that the secondary poisoning effect was much reduced under the continuous baiting strategy, compared to the initial 1080 poison operation. Chapter V. Managing alien mammals in mainland New Zealand: The implications for predator/prey interactions in complex communities. Recent advancements in alien pest mammal control technologies have enabled conservation managers to attempt long term, large scale, predator and browser control programmes at mainland sites in New Zealand. At Trounson Kauri Park (in Northland, New Zealand) feral cats, ferrets, stoats and weasels plus rodents and possums were controlled for two and a half years. Early results from Trounson suggested that some native birds and plants responded positively and quickly to the control of these alien pest mammals. However, the management also affected the predator-prey and predator-predator interactions, within the mammalian community, with changes in the predator guild and some prey species increasing in abundance. The long term effects of these responses within the mammalian community to control efforts are unclear. A review of the international literature served only to confirm the view that managing alien mammals where re-invasion is constant will be a complex task. Conservation management at mainland sites like Trounson Kauri Park, may in effect be acting as crude mammalian predator removal experiments. Monitoring changes in predator-prey interactions and predator-predator interactions at this and other intensive management sites over sufficient time frames could provide scientists with the critical ecological data required to construct useful predictive models. The ability of managers to target specific pests at critical times would represent a significant advancement in controlling predatory mammals on the New Zealand mainland.

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43

Adeeb, Farah. "A Study of near-surface ozone concentrations in the city of Auckland, New Zealand." 2006. http://hdl.handle.net/2292/2571.

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This research provides insight into large-scale spatial variation of ozone (O3) distribution in the Auckland region and was designed to increase our understanding of O3 behaviour and distribution in a coastal-urban situation. The research was also carried out with a view to assisting regulatory agencies optimize future monitoring networks, and to help identify locations where human health and natural resources could be at risk in the future. Although the research was limited to one region, the results are valuable for improving the conceptual understanding of formation of high ozone concentrations in a more general sense in the New Zealand and Southern Hemisphere. The work reported in this thesis is aimed at studying O3 concentrations and the influence of the most relevant meteorological variables on an average coastal New Zealand city where precursor emissions are mainly due to traffic exhaust. It deals with the use of Principal Component Analysis method for determining O3 concentrations as a function of meteorological parameters. The study region includes the entire Auckland isthmus, and extends from Whangaparaoa in the North to Pukekohe in the South. Surface O3 data from four sites (Whangaparaoa, Musick Point, the Sky Tower and Pukekohe) for a 4-year period(October 1997 to October 2001) for the Auckland region were examined. Ambient concentration of O3 was characterized in terms of diurnal, weekday/weekend, seasonal and spatial variations in concentration using O3 measurements from the four air quality sites. The monthly average ambient background O3 concentrations at the monitoring sites during this study ranged from 16-30 ppb, much lower than those found in the Northern Hemisphere. The measured seasonal O3 record in the Auckland region, in common with many other remote sites in the Southern Hemisphere, exhibited a summer minimum and a winter maximum. Background concentrations of O3 (as seen in air of marine origin) made a significant contribution to the observed ambient concentrations. A unique feature of Auckland's air quality was the dilution of polluted city air due to the mixing of east coast air into the cleaner west coast circulation leading to overall lower average O3 concentrations in summer. The magnitude, frequency and spatial extent of maximum O3 concentrations were identified, and the observed patterns linked to the prevailing meteorological, topographic, and emission characteristics of the region. However, at no time at any site or season did the O3 concentration exceed the l-hour New Zealand Ministry for the Environment guideline of 75 ppb. O3 depletion was observed to occur at the urban sites, with O3 scavenging by nitric oxide believed to be the dominant depletion mechanism. The seasonal cycle was characterized by elevated O3 concentrations in the winter (nighttime level >24 ppb) and low mixing ratios in the summer (nighttime levels in the range 14-20 ppb). The afternoon O3 maxima found at the three low elevation sites under the impact of "Auckland city" plume were on average, 1.5 to 1.7 times higher than those associated with the "marine sector". A state of the art diagnostic meteorological model, namely CALMET, was used to generate wind fields for the Auckland region. These wind fields were then used to construct backward trajectories on days when high O3 concentrations (episodes up to 6l ppb) were observed. The un-even distribution of the meteorological monitoring sites provided justification for running the diagnostic model CALMET and exploring the utility of using such a model when topography/land use prohibits monitoring sites in certain sections of the domain. It was found that the high O3 events recorded at the monitoring sites during the study period coincided with transport episodes originating from Auckland's urban and industrial areas. For the occurrence of high O3 concentrations at downwind sites, it was found that not only wind direction from the urban areas of Auckland, but that high solar radiation was important as well. On four out of the five cases when photochemical production of O3 was found to occur, high O3 concentrations were associated with a particular type of diurnal evolution of wind direction wind fields associated with the sea breezes. In addition to the analysis of ambient o3 concentrations and O3 episodes, field measurements were carried out in an attempt to detect and subsequently understand the interaction between particulate matter and O3 in the Auckland region, a multivariate statistical analysis approach was utilized. Particulate matter in the size range 2.75-6.25 μm accounted for over 70% of the total aerosol concentration at all sampling sites. Surface area of particulate matter variable (especially in the size class 2.75-4.25 μm) was statistically significant in explaining variation in O3 concentration. However, the net change in the adjusted R2 indicated that the effect of adding particulate matter in the multiple regression model for the present dataset was relatively minor except at Musick Point.

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Boxall, Naomi. "The epidemiology of Campylobacter jejuni in commercial broiler flocks in New Zealand : a thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy at Massey University, Palmerston North, New Zealand." 2005. http://hdl.handle.net/10179/1589.

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New Zealand maintains the highest incidence rate of human campylobacteriosis of the industrialized countries (334.2 cases per 100,000 in 2002), it accounts for more than 56% of all disease notifications in the country. New Zealand is unique globally, with a 'notification-based surveillance system for notifiable diseases that is complemented by laboratory reporting. In other countries (Australia, US, UK), the notification system is entirely laboratory based. Thus, the high incidence of Campylobacteriosis in humans may be related to the methods of reporting rather than the reality of the disease situation. However, the reason for such high incidence has not yet been fully elucidated, and several studies conducted in New Zealand and overseas have implicated the consumption of poultry meat as the main cause of human infections. The reduction or elimination of Campylobacter jejuni in the food chain, particularly from poultry meat products, is a major strategy in efforts to control campylobacteriosis. One approach to this is to prevent C. jejuni colonization of broiler chickens, This approach has been used to control Salmonella contamination of poultry, but the measures put in place for control of Salmonella have not controlled C jejuni. It is generally unknown how frequently C. jejuni colonizes commercial broiler chickens in New Zealand, or what could be done to prevent these infections from occurring. The present study was undertaken in order to describe some of the basic epidemiology of C. jejuni in commercial broiler flocks in New Zealand. The thesis is intended to further describe the epidemiology of colonisation of commercial broiler chickens by C. jejuni in NZ, and present possible risk factors that could be controlled in future to decrease the number of positive flocks of birds that are processed. The thesis set out to elucidate first the extent of C. jejuni colonisation of birds, flocks and farms while the birds were on the farm, having had minimal risk of exposure to Campylobacter spp., by sampling 15 birds in 80 flocks belonging to two companies prior to the first partial depopulation, an event during which the flock are exposed to potentially contaminated fomites and biosecurity levels are dropped, doors opened and personnel movements are extensive. The resulting prevalence estimates are 25.6% of farms, and 12.5% of sheds, are likely to be used to rear broiler chickens colonised with C. jejuni. When a positive flock is discovered, 76.9% of the birds are likely to be colonised with C. jejuni. These figures are results across the whole study population of farms and sheds, as there were no significant differences between prevalence estimates between companies. Following this prevalence estimation, a longitudinal study was conducted involving 12 sheds, to determine whether the environment or the birds were colonised with C. jejuni first. Although 12 sheds were observed every other day from day 14 to the end of the rearing period, it was determined that the birds were positive either first, or at the same time as the environment. Having said that, the sensitivity of the testing method for the environment was dubious, as there were instances where a shed that had positive samples collected on one occasion appeared negative the next, before returning a positive result on the third consecutive sampling occasion. A cross-sectional study of 810 flocks was undertaken to determine the most relevant risk factors for colonisation of the broiler chickens with C. jejuni. Because of the vertically integrated structure of the poultry industry, these 810 flocks corresponded to data collected from 77 farmers about their farms and the 219 sheds on those farms. The caeca from ten birds from each flock processed were pooled and examined for the presence of C. jejuni. These results were used to create a case definition, such that the flocks could be analysed with the questionnaire data, and different risk factors were seen in each season. More flocks reared for Company One were colonised by C. jejuni than for Company Two. Protective factors included having hard (i.e. gravel, asphalt or concrete) pathways to the growout houses, being near to another broiler farm, using the reticulated town water supply for the birds drinking water, using tunnel or crossflow shaped growout houses, using a Chore-TimeTM feed delivery system within the growout house and chlorinating the water supply to the birds (only in winter). The odds of raising flocks colonised with C jejuni increased if rodents were seen on the farm, if the growout houses were constructed with a concrete nib wall, if gas heaters were used during brooding, if cattle were farmed on the property, or if workers were employed on the farm. Sanitising the annex at least as frequently as once per run decreased the odds during summer, and tended to have a similar effect in other seasons. Chlorinating the water supply appeared to have a protective effect in only one season, though the trend appeared towards protection in the other seasons. The risk factor was validated by sampling the drinking water that broilers chickens had access to for the FAC to sec whether the levels that were present in the drinking water could have an effect on C. jejuni 11 sheds that were known to chlorinate the water were sampled to determine whether they met the drinking water standards for humans in NZ, or met the requirements presented by one of the companies involved. Only three sheds met the human drinking water standards for FAC, and two of these (one from each company) met Company Two's requirements. This thesis is for both regulatory and industry stakeholders to assist with developing risk management approaches to diminishing the number of C. jejuni positive flocks. Where management practices are altered, it is hoped that the efficacy of such practices be measured by examining the changes in the rates of C jejuni colonization within the industry

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Okeoma, Chioma Maureen. "Studies on Neospora caninum and neosporosis in New Zealand cattle : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Animal Science, Massey University, Palmerston North, New Zealand." 2005. http://hdl.handle.net/10179/1643.

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Content removed due to copyright restrictions: Okeoma, C. M., Stowell, K. M., Williamson, N. B., & Pomroy, W. E. (2005). Neospora caninum: Quantification of DNA in the blood of naturally infected aborted and pregnant cows using real-time PCR. Experimental Parasitology, 110(1), 48-55. Okeoma, C. M., Williamson, N. B., Pomroy, W. E., Stowell, K. M., & Gillespie, L. M. (2004). Isolation and molecular characterisation of neospora caninum in cattle in new zealand. New Zealand Veterinary Journal, 52(6), 364-370. Okeoma, C. M., Williamson, N. B., Pomroy, W. E., Stowell, K. M., & Gillespie, L. (2004). The use of PCR to detect neospora caninum DNA in the blood of naturally infected cows. Veterinary Parasitology, 122(4), 307-315. Okeoma, C. M., Williamson, N. B., Pomroy, W. E., & Stowell, K. M. (2004). Recognition patterns of neospora caninum tachyzoite antigens by bovine IgG at different IFAT titres. Parasite Immunology, 26(4), 177-185.
The objective of this research was to investigate neosporosis in New Zealand cattle using experimental and molecular tools. The research also aimed to isolate and characterise an indigenous New Zealand isolate of Neospora caninum. A series of discrete projects were conducted to achieve the set objectives. A pilot study was first conducted and a wild-type strain of non-cytopathic bovine viral diarrhoea virus (BVDV) type 1 virus was isolated in vitro from a persistently infected heifer. The isolate was used to challenge heifers and the effect of experimental BVDV infection on heifers naturally infected with N. caninum was investigated. Results showed that heifers that were both BVDV and N. caninum seropositive produced 44.4% (8/ 18) damcalf pairs that were both BVDV and N caninum seropositive. Serologically, 66.7% (12/18) dam-calf pairs were seropositive to N. caninum antibodies, while 80% (8/10) dam-calf pairs were BVDV seropositive. A Polymerase Chain Reaction (PCR) study was also conducted and N. caninum DNA was detected in the blood of naturally infected aborting and pregnant heifers. Real-time quantification of N. caninum DNA in the blood of infected heifers showed a decrease of N. caninum DNA after abortion in the aborting group and an increase through gestation in the pregnant group. A study of antigenicity recognised 7 immunodominant (~18, ~25, ~33, ~35~36, ~45~46, ~47 and 60-62 kDa) and 5 minor antigens of N. caninum by cow sera. Three isolates of N. caninum (NcNZ 1 ,NcNZ 2 and NcNZ 3) were isolated from the brains of an infected cow, her calf and a stillborn calf. These isolates were confirmed as N. caninum by PCR, immunofluorescence antibody test and immunohistochemistry and were pathogenic to BALB/c mice.

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DeNicolo, Gina. "Accelerated and out-of-season lamb production in New Zealand : a thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy at Massey University, Palmerston North, New Zealand." 2007. http://hdl.handle.net/10179/775.

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The objective of this study was to evaluate ewe and lamb performance in an accelerated lamb production system, and to compare the performance and lamb output between a conventional and an accelerated lamb production system. In the “Conventional” system, ewes were bred in March to lamb in August. The “Accelerated” system was based on the “STAR” system (Lewis et al., 1996), in which there were five breeding periods within each year. In the current experiment these were 14th January, 28th March, 9th June, 21st August and 2nd November. Progesterone was used to synchronise the breeding periods and during the non-breeding season, eCG was used to induce reproductive activity. Lambing began on each of these dates and weaning was 73 days later, coinciding with the next breeding period. The experiment ran over a three-year period beginning with breeding in March 2003 and was complete with the weaning of lambs from the January 2006-bred ewes. This resulted in 15 lambing and breeding periods over the three years in the Accelerated system and three lambing and breeding periods in the Conventional system. Average pregnancy rates were lower in the Accelerated system than in the Conventional system. Lamb growth rates were similar between the two systems, although lamb live weights at weaning were lower in the Accelerated system due to the age of the lambs at weaning (average = 69 vs 96 days). More lambs were born and weaned, resulting in more kilograms of lamb weaned in the Accelerated system relative to the Conventional system over the experimental period (26,200 vs 24,300 kg). Labour input was 35% higher in the Accelerated system, or 13% higher per lamb weaned. Average annual ewe energy requirements were 6% higher in the Accelerated system. Ewe energy requirements per kilogram of lamb weaned was lower (6%) in the Accelerated system due to more breeding and lambing periods per ewe per year. Laparoscopic observation of ewes’ ovaries at each breeding period revealed that most ewes had active ovaries and were therefore capable of successfully producing a viable foetus. In a subsequent experiment, blood samples were collected for analysis of progesterone concentrations from ewes bred during the spring and autumn breeding periods. Observations of data indicated that a small number of ewes conceived and lost their conceptus, or had abnormal corpora lutea. Results suggested that pregnancies were failing due to a lack of an appropriate signal from the embryo to the dam/uterus. Exposing Romney ewes to an artificial lighting regimen was unsuccessful for inducing reproductive activity during spring. In another experiment, melatonin implants administered to Romney ewes in spring and used in conjunction with eCG and progesterone, resulted in 61% more lambs born per ewe treated, compared to eCG and progesterone alone. This result indicated that melatonin implants, used with eCG and progesterone may be a suitable method for improving reproductive performance in sheep bred out of season in New Zealand. Delaying weaning of lambs and breeding lactating ewes can be used to obtain heavier lamb weaning weights in the Accelerated system. Spring-bred ewes had lambs weaned at either 69 days post partum or 90 days post partum. Reproductive performance was similar between the two groups of ewes, and lamb live weights in the later weaned group were heavier when lambs were 90 and 120 days of age. This research has shown that accelerated or out-of-season lamb production is an option for some New Zealand sheep farmers. However, the mechanisms associated with reproductive seasonality and methods of successfully circumventing this seasonality require further attention in order to achieve optimum reproductive performance.

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Ayanegui, Alcérreca María Alejandra. "Epidemiology and control of leptospirosis in farmed deer in New Zealand : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Veterinary Clinical Science at Massey University, Palmerston North, New Zealand." 2006. http://hdl.handle.net/10179/1470.

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Missing pages 93, 264 & 313 from electronic and Vault (preservation) copy.
Leptospirosis has been reported in farmed deer in New Zealand since 1980 but knowledge was limited. Studies presented in this thesis investigated the epidemiology and distribution of infection associated with serovars Hardjobovis, Pomona, and Copenhageni in farmed deer, efficacy of a vaccine and the influence of maternally derived antibody, and aspects of exposure of humans to leptospirosis. Serology, bacteriology, and pathology were employed as determinants of infection and vaccine efficacy. A serological survey of 2016 deer from 110 herds confirmed leptospirosis throughout New Zealand with 61.3% of herds infected with Hardjobovis and 3.6% with Pomona alone, 16.4% with dual infections with those serovars, and none with Copenhageni, giving an overall herd prevalence of 81.3%. Epidemiological studies involved serological analysis of samples from a serum bank involving weaner, yearling and adult deer (n=10/group) from 15 farms sampled 3-monthly for 21 months, and intensive blood and urine sampling of young deer on three farms over 1-2 production cycles (n=15-65/group). Infection with Hardjobovis followed an age-related endemic cycle with some animals infected by 3-4 months of age and seroconversion peaking at up to 57% at 12-15 months and mild kidney lesions typical of a host-adapted organism. Infection with Pomona followed an epidemic pattern with seroprevalence of up to 100%, more severe kidney lesions, clinical signs and evidence of reduced growth and reproduction, typical of an accidental host relationship. Leptospira were observed in 30.4% of urine samples and 37.0% of kidneys. Vaccination with "Leptavoid 3" (Schering-Plough Animal Health Ltd) was studied on one non-infected, one Hardjobovis infected, and two dual Hardjobovis/Pomona infected herds. Vaccination produced sustained titres in uninfected young and adult deer, and no maternally derived antibody interference was observed in progeny vaccinated at approximately 3-4 months of age. In infected herds, vaccination enhanced seroprevalence and antibody titres, and reduced urine shedding by 44% and culture from urine and kidneys by 37% in the face of continued natural challenge. Analysis of previous data combined with pooled data from the above studies, indicated that 73.0% of lines and 29.0% of individual deer at slaughterhouses had kidney lesions indicative of leptospirosis with a relative risk (RR) of 1.08 and 1.6 for the relationship between seropositivity to Hardjobovis and Pomona, respectively. The overall RR between positive serology, lesion and culture was 2.1. The kidney culture rate ranged from 2.5-33% between herds demonstrating significant risk of exposure to humans, particularly slaughterhouse workers. This study has provided an understanding of the epidemiology in farmed deer and control options available to the industry.

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Perkins, Nigel Ross. "Epidemiology of health and performance in New Zealand racehorses : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Veterinary Epidemiology at Massey University, Palmerston North, New Zealand." 2005. http://hdl.handle.net/10179/1580.

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The aim of this research was to describe training and racing patterns, and causes of wastage in New Zealand Thoroughbred racehorses. Two separate studies were performed. The first involved analysis of data from before and after construction of a new training track at the Matamata Racing Club. Comparisons of measures of performance failed to detect any adverse impact that could be attributed to the new track. The second involved a longitudinal study over a 34-month period, and that involved 1,571 horses. Duration of training preparations and spell periods were associated with horse age, and with the reason for ending a training preparation. Most horses began a training preparation doing slow work and then progressively advanced to a first start. Incidence rates were estimated for starts per 100 training-days, and other summary measures were estimated including training-days to first start, and between successive starts. A total of 834 musculoskeletal injuries (MSI) were observed, resulting in either a spell period, retirement, or death of the horse. There were 165 respiratory disease events, and 58 conditions involving other body systems. Multivariate statistical models were used to explore risk factors for different types of MSI. Older horses were at higher risk of lower limb MSI, and injury to either the superficial digital flexor tendon (SDFT) or suspensory apparatus (SA), while they were at lower risk of shin soreness and other conditions. Male horses had higher risk of tendon and ligament injury than females. Lower risk of injury was observed in Autumn and Winter months compared with December, and in the 1999-2000 year relative to 1997-1998. Measures of cumulative exercise intensity showed a complex relationship with risk of injury that varied with type of injury. The risk of SDFT and SA injury was higher for those preparations without starts, while that for shin soreness was increased after the first start. For lameness conditions other than shin soreness or injury to the SDFT, the hazard was increased after the first start in a preparation, but the magnitude of effect was dependent on the number of days from the beginning of a preparation to the first start.

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Lawrence, Hayden George. "Adoption of precision agriculture technologies for fertiliser placement in New Zealand : a thesis presented in partial fulfilment of the requirements of the degree of Doctor of Philosophy in Agricultural Engineering at Massey University, Palmerston North, New Zealand." 2007. http://hdl.handle.net/10179/1429.

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Major agronomic and economic losses are caused by inaccurate application of nutrients from ground based spreading vehicles. These losses come from both over and under application of fertiliser resulting from such practices as driving at inappropriate bout widths. This work reviewed current spreader testing procedures; compared the performance of international test methodologies and evaluated the use of a digital image processing program to perform spreader testing. Methods to evaluate field performance were developed; this analysis of field application was used to calculate the economic effect of using precision agricultural technologies in New Zealand dairy farming systems. A matrix of fourteen hundred 0.5 x 0.5 m fertiliser collection trays was used to evaluate individual test methodologies. Results indicated that there were major variations in calculated certifiable bout width between different methods and direct comparison should be avoided. Tray layout within ± 5 m of the centre spread line had the largest effect on calculated bout width whilst methods that incorporated rows of trays in the longitudinal direction were less variable compared to those using a single transverse test. The probability too accurately assign bout widths using different international test methods was analysed, the ACCU Spread (Australia) test method had the highest level of confidence in its bout width calculation followed by the ES (Europe) test method. The ISO(i) (World), ISO(ii) (World) and Spreadmark (NZ) tests were all found to be comparable to one another whilst the ASAE (USA) method had the lowest level of confidence in its bout width calculation because of wide collector tray spacing. A method to extract a wider range of data from spreader tests using a hybrid image processing system was developed. Results indicated that there was a strong relationship between two dimensional particle area and particle mass under laboratory (R2 = 0.991) and field (R2 = 0.988) conditions. Although transverse spreader tests provided a good indication of machine performance, they did not account for the interaction of the spreader and its operational environment. A method was developed that used the vehicle location during field application and the transverse spread pattern represented as polygons to create field application maps. Initial results showed large variations compared to the measured transverse spread pattern. A wider study over 102 paddocks on four dairy farms showed that average variation was 37.9%. An improvement to the field application method discussed is given; this tool used the geographical position, heading angle and a series of static spread pattern tests from the spreading vehicle to achieve greater accuracy in field measurements. The described field application methods were used to assess the ability to execute a nutrient plan using both actual and optimised spreading data collected during field application. A loss of $66.18 ha-1 was calculated when comparing the efficiency of using current spreading methods to those assumed in nutrient budgeting practice. If a guidance and control system were used correctly to provide optimised field application the loss could be reduced to $46.41 ha-1. This work highlighted the difficulties in achieving accurate field nutrient application; however, by developing the ability to quantify field performance, economic opportunities could be evaluated. Overall, this work found that there was a strong agronomic and economic case for the implementation of precision agricultural technologies in the New Zealand fertiliser industry. However, the current range of equipment used by the spreading industry would have difficulty in delivering these benefits.

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Subharat, Supatsak. "Epidemiology, diagnosis and vaccination control of leptospirosis in farmed deer in New Zealand : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Veterinary Clinical Science at Massey University, Palmerston North, New Zealand." 2010. http://hdl.handle.net/10179/1678.

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Leptospirosis is a bacterial zoonotic disease of global importance. It is caused by infection with pathogenic Leptopsira species. Leptospirosis encompasses a wide spectrum of clinical or subclinical disease in both humans and animals. In New Zealand (NZ), leptospirosis is considered to be the most important occupational zoonosis. Livestock farming plays an important role as a major occupational risk factor for human leptospirosis and farmed deer is one of the contributing factors. Commercial farming of deer began in NZ in the early 1970s. It remains the world’s largest and most advanced deer farming industry. Leptospirosis in farmed deer can cause illness and possibly sub-clinical production losses. Farmed deer also play an important role in the transmission of leptospirosis by shedding the organisms in their urine, putting both other animals and humans at risk. Leptospira serovars Hardjobovis and Pomona are the most commonly found serovars in this stock group. The first substantial case report of leptospirosis in farmed deer was in the 1980s but it was not until 2006 that a substantial epidemiological study of this disease in farmed deer was reported. The purpose of this research was to improve and extend current knowledge on the epidemiology of leptospirosis on mixedspecies deer farms, to develop and validate a novel molecular diagnostic tool and to enhance understanding of control measures and their outcomes by means of vaccination. A pilot longitudinal seroprevalence survey of leptospirosis on mixed-species deer farms was conducted. Results from this study revealed that leptospiral infection averaged 70% in all species on mixed-species farms in the lower North Island of NZ. Co-grazing with infected sheep and/or cattle was positively associated with deer herd serological status to both serovars Hardjobovis and Pomona which suggests the possibility of inter-species transmission. Results from this study justify further investigation of leptospirosis on mixedspecies farm at the national level. A collaborative study between Massey University and the WHO/FAO/OIE reference laboratory for leptospirosis in Brisbane to investigate for exotic serovars in farmed deer revealed seropositivity to Arborea which has never been found before in NZ. Attempts to isolate Arborea from kidney samples of farmed deer were unsuccessful and require further investigation. Real-time PCR assay was developed and validated against culture as the gold standard for use on deer kidney tissue and urine as a research and diagnostic tool for determining infection, carrier and shedding status of deer. This research revealed that the real-time PCR assay was highly sensitive (sensitivity: 85% for kidney and 96.7% for urine) and specific (specificity: 99.2% for kidney and 100% for urine). It is a useful tool for the rapid and cost-effective detection of pathogenic leptospires in clinical samples. It can also be used to quantify the concentration of leptospires from clinical samples and identify the likely infecting serovar in NZ when adjunct with a DNA sequencing technique. Vaccination control for leptospirosis has proven to be efficacious and likely to be costeffective. Present research has determined the effect of a commercial bivalent leptospiral vaccine (Leptavoid-2, Intervet/Schering-Plough Animal Health Limited, NZ) on leptospiral shedding, growth and reproduction of farmed deer under NZ pastoral conditions. The study was designed to simulate an infection-free herd scenario followed by exposure to natural challenge. Results have shown the potential of vaccine to improve mean weight gain (up to 6.5 kg) and weaning rate (average 6.9%) in infected herds and prevent urinary shedding after natural challenge with Hardjobovis. It also provides the first evidence of adverse subclinical effects on deer production by Hardjobovis alone. A pilot study to investigate the presence and localisation of pathogenic Leptospira in the uterus and foetus of female deer revealed evidence of a foetal infection using real-time PCR. This finding suggests a possible explanation for effects of leptospiral infection on NZ farmed deer reproduction. However, further study is required to justify this proposition. This research has contributed significantly to understanding of epidemiology of leptospirosis in NZ farmed deer, providing objective data to assist producers in decision-making on leptospirosis control. Furthermore, this study has made available a valuable diagnostic resource for future leptospirosis studies, and has provided direction for future research into leptospirosis on farmed deer and mixed-species farms.

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Dissertations / Theses on the topic 'New Zealand. Agricultural Research Division'

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