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1
Gillespie, J. H., C. Geissinger, F. W. Scott, W. P. Higgins, D. F. Holmes, M. Perkus, S. Mercer, and E. Paoletti. "Response of dairy calves to vaccinia viruses that express foreign genes." Journal of Clinical Microbiology 23, no. 2 (1986): 283–88. http://dx.doi.org/10.1128/jcm.23.2.283-288.1986.
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Byzova, N. A., E. A. Zvereva, A. V. Zherdev, and B. B. Dzantiev. "Immunochromatographic technique for express determination of ampicillin in milk and dairy products." Applied Biochemistry and Microbiology 47, no. 6 (October 26, 2011): 627–34. http://dx.doi.org/10.1134/s0003683811060032.
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Çukur, Tayfun. "Factors Affecting Dairy Farmers’ Application of Agricultural Innovations: A Case Study from Muğla Province." Turkish Journal of Agriculture - Food Science and Technology 4, no. 7 (July 15, 2016): 611. http://dx.doi.org/10.24925/turjaf.v4i7.611-617.713.
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The main objective of this study is to determine the factors affecting the application of innovations for dairy farmers in the Milas district, Muğla province, Turkey. Data from 71 dairy farmers and the Multinominal logit model are used for this study. The dependent variable of the model is divided into three categories; “I don’t apply any agricultural innovations”, “I apply agricultural innovations only after other farmers apply and express their positive opinion” and “I apply agricultural innovations”. In conclusion of the analysis, the comparisons are done with the farmers who “do not apply any agricultural innovations,” and the farmers who “apply agricultural innovations only after other farmers apply and express their positive opinion”; it is determined that a one unit increase in educational level raised the likelihood of applying innovations after receiving positive opinion. When the farmers that “apply agricultural innovation”, and that “apply agricultural innovations only after other farmers apply and express their positive opinion” are compared, it is found that a one unit increase in the number of milking animals had increased the likelihood of applying the innovations.
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Iqbal, Aamir, Abdul Qudoos, Ismail Bayram, O. Tytariova, V. Bomko, O. Kuzmenko, and O. Cherniavskyi. "Heat stress in dairy cows." Tehnologìâ virobnictva ì pererobki produktìv tvarinnictva, no. 1(164) (May 25, 2021): 7–13. http://dx.doi.org/10.33245/2310-9289-2021-164-1-7-13.
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This review includes an analysis of the literature on various influencing factors influencing heat stress in lactating dairy cows and the way it affects milk production. Signs and symptoms of heat stress in cows are reduced feed consumption and decreased milk yield, elevated breathing rate, increased body temperature and reduced reproductive overall performance. There are other problems for example, a seasonal growth in bulk tank somatic cell counts. The birth weight is decreased in cows which have been exposed to heat stress throughout the dry length. It is established that the most critical is the heat accumulated via direct radiation from the solar. It was found out that high feed consumption results in raised metabolic heat increment. High metabolic warmness increment requires powerful thermoregulatory mechanisms to maintain body temperature in a thermoneutral area and in physiological homeostasis. It is confirmed that heat stress is complicated because the responses to heat stress have an effect on not best the energy stability, but also water, sodium, potassium and chlorine metabolism. Plasma progesterone degrees may be elevated or reduced depending on whether or not the heat pressure is acute or chronic. Water, sodium, potassium and chlorine are vital constituents of sweat, and sweating is a chief, if not the most important, thermoregulatory mechanism used to burn up extra body heat. Strategies to reduce heat stress must be evolved to enable cows to express their full genetic ability. Key words: dairy cows, heat stress, thermoregulatory mechanism, water, feed consumption, mineral elements.
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Mladenov, Mirolyub. "Complex Assessment of Dairy and Meat Products Quality." Information Technologies and Control 13, no. 3-4 (December 1, 2015): 7–19. http://dx.doi.org/10.1515/itc-2016-0012.
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Abstract This paper presents a new approach and a platform for complex, non-destructive, express evaluation of quality and safety of food products, based on analysis of visual images, spectral and hyperspectral characteristics, followed by fusion the results of these analyzes. The aim is categorization of the investigated products in quality groups. The complex evaluation includes: assessment of the appearance and visual characteristics of the investigated product, evaluation of properties associated with the product composition and with the distribution of the properties on its surface. The focus is on main indicators of quality and safety of basic foodstuffs, such as meat, structural bacon, white brined cheese and yellow cheese. The following main tasks are discussed: 1) The formal description of the investigated objects; 2) The extraction of specific quality features; 3) The evaluation of classes’ data separability; 4) The classification of the foodstuffs in quality groups.
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Simão, Gustavo Leonardo, Luiz Marcelo Antonialli, Túlio Carvalho C. de Souza Netto, and Antonio Carlos dos Santos. "Strategic Institutional Management in Dairy Cooperatives - a theoretical appointment." Revista de Economia e Sociologia Rural 55, no. 4 (December 2017): 693–710. http://dx.doi.org/10.1590/1234-56781806-94790550405.
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Abstract: The competitive agribusiness environment has been pressing organizational actors of dairy cooperatives to implement new structures. In this sense, many scholars advocate the existence of isomorphic practices that are not suitable for cooperative enterprises. This theoretical paper assumes that there are strategic actions related to the institutional demands, implemented by cooperative decision makers in relation to environmental pressures. Thus, we aimed to analyze how can be structured such strategic actions in relation to the institutional pressures of two organizational subfields related to cooperative business, in order to maintain the legitimacy of the business. For this, we drafted the projection of five analytical frameworks. As conclusions, it is inferred that a cooperative business restructuring not always tends to express an atomism of decision makers in relation to institutional demands of the organizational field, given that the demands are ambivalent and need to be met in order to obtain minimum level of legitimacy necessary for the organization survival.
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Hristov, Slavca, B. Stankovic, Z. Zlatanovic, M. Joksimovic-Todorovic, and V. Davidovic. "Rearing conditions, health and welfare of dairy cows." Biotehnologija u stocarstvu 24, no. 1-2 (2008): 25–35. http://dx.doi.org/10.2298/bah0802025h.
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This paper provides an overview of recent developments in rearing conditions, health and welfare issues of dairy cows. The last approximately 30 years has witnessed worldwide increasing scientific research, consumer activity, and political response towards housing condition, health and welfare issues of dairy cattle. All buildings and housing systems for dairy cattle should be designed, constructed, maintained and managed to assist in the achievement of the Five Freedoms: freedom from hunger and thirst, freedom from discomfort, freedom from pain, injury and disease, freedom to express normal behavior and freedom from fear and distress. Whether dairy cows are housed in cubicles, straw yards or cow sheds, in order to maximize their performance and to ensure satisfactory standards of welfare, the accommodation must provide the most basic behavioral and physiological needs. As an absolute minimum, the housing must provide a comfortable, clean, well drained and dry lying area together with shelter from adverse weather. Also, it must allow the cow to move freely around without risk of injury and certain diseases. If the housing system does not provide for these basic needs, then not only will health, welfare and production of dairy cattle be compromised, but it is likely that failure to comply with the welfare codes and the law relating to animal welfare will occur.
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Park, A. F., M. V. Sheffel, Evan C. Titgemeyer, and John E. Shirley. "Extruded-expelled cottonseed meal (express) as a source of protein and fat for lactating dairy cows." Kansas Agricultural Experiment Station Research Reports, no. 2 (January 1, 1998): 40–42. http://dx.doi.org/10.4148/2378-5977.3234.
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Morris, Sarah P. "Dairy Queen. Churns and milk products in the Aegean Bronze Age." Opuscula. Annual of the Swedish Institutes at Athens and Rome 7 (November 2014): 205–22. http://dx.doi.org/10.30549/opathrom-07-12.
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This article assembles examples of an unusual vessel found in domestic contexts of the Early Bronze Age around the Aegean and in the Eastern Mediterranean. Identified as a “barrel vessel” by the excavators of Troy, Lesbos (Thermi), Lemnos (Poliochni), and various sites in the Chalkidike, the shape finds its best parallels in containers identified as churns in the Chalcolithic Levant, and related vessels from the Eneolithic Balkans. Levantine parallels also exist in miniature form, as in the Aegean at Troy, Thermi, and Poliochni, and appear as part of votive figures in the Near East. My interpretation of their use and development will consider how they compare to similar shapes in the archaeological record, especially in Aegean prehistory, and what possible transregional relationships they may express along with their specific function as household processing vessels for dairy products during the third millennium BC.
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Gudaj, R. T., E. Brydl, J. Lehoczky, and I. Komlósi. "Study of animal welfare status in dairy cow herds in Hungary." Biotehnologija u stocarstvu 28, no. 3 (2012): 509–16. http://dx.doi.org/10.2298/bah1203509g.
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Animal welfare is a hot topic among consumers, producers and researches nowadays. The major welfare problems of dairy cows are mastitis, lameness, and any conditions which lead to impaired reproduction, inability to express normal behaviour, emergency physiological responses or injury. This paper summarizes preliminary results of project taken in 27 Hungarian dairy farms evaluating general animal welfare. The most important areas for improving animals? wellbeing are related to facilities and comfort of resting. Findings include slippery floors, cows struggling laying and standing in cubicles. Other measures include hair loss, hocks, neck rail injuries and number of thin cows (Body Condition Score 1 and 2). Mouldy silage and low quality of other feedstuff was also found. In conclusion, preliminary results confirm strong demand for monitoring farms and discussions with managers and farmers about welfare measures needed to be taken on farms immediately.
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Silbernagel, Karen M., Robert P. Jechorek, Charles N. Carver, Barbara L. Horter, Kathryn G. Lindberg, V. Aleo, G. Anderson, et al. "3M™ Petrifilm™ Staph Express Count Plate Method for the Enumeration of Staphylococcus aureus in Selected Dairy Foods: Collaborative Study." Journal of AOAC INTERNATIONAL 86, no. 5 (September 1, 2003): 963–70. http://dx.doi.org/10.1093/jaoac/86.5.963.
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Abstract The 3M™ Petrifilm™ Staph Express Count plate method was compared with AOAC Official Method 975.55 for the enumeration of Staphylococcus aureus in selected foods. Five foods—ice cream, raw milk, yogurt, whey powder, and cheese—were analyzed for S. aureus by 12 collaborating laboratories. For each food tested, the collaborators received 8 blind test samples consisting of a control sample, a low inoculation level, a medium inoculation level, and a medium inoculation level with background flora, each in duplicate. The mean log10 counts for the methods were comparable for all 5 foods. The repeatability and reproducibility variances of the 24 h Petrifilm Staph Express Count plate method were similar to those of the 72 h standard method.
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Miller, L. A., M. A. Neville, D. H. Baker, R. T. Evans, M. K. Theodorou, J. C. MacRae, M. O. Humphreys, and J. M. Moorby. "Milk production from dairy cows offered perennial ryegrass selected for high water soluble carbohydrate concentrations compared to a control grass." Proceedings of the British Society of Animal Science 1999 (1999): 208. http://dx.doi.org/10.1017/s175275620000363x.
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The efficiency of grass nitrogen utilisation for milk production tends to be low, due partly to the slow rate of release of energy in the rumen which reduces the efficiency of capture of rapidly degradable plant proteins by the rumen microbial population. When additional sugars are infused into the rumen, microbial protein production is increased (Rooke et al., 1987). The objective of this study was to assess milk production using a grass variety that has been bred to express elevated water soluble carbohydrate (WSC) concentrations.Eight multiparous Holstein-Friesian dairy cows in mid lactation (176 days ± s.e. 3.6) were used in a continuous design, zero-grazing experiment. Following covariate measurements taken from all animals on a standard grazing diet, four animals were each offered one of two varieties of perennial ryegrass at ad libitum rate: AberDove, bred to express high WSC concentrations; and AberElan, a commercially available variety, used as a control.
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Ostojic-Andric, Dusica, Slavca Hristov, Milan Petrovic, Vlada Pantelic, Dragan Niksic, Violeta Caro-Petrovic, and Branislav Stankovic. "The state of welfare on Serbian dairy farms." Biotehnologija u stocarstvu 32, no. 3 (2016): 239–49. http://dx.doi.org/10.2298/bah1603239o.
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The aim of this study was to analyze the overall welfare state on Serbian dairy farms, as well to suggest measures for its improvement. The assessment was done according to Welfare Quality? Assessment Protocol for Dairy Cows on 16 selected commercial farms in which the cows of Simmental and Holstein-Friesian breeds were reared (N=4833). Welfare state on each farm was evaluated by relevant measures that indicated insurance of appropriate feeding, housing, health and behavior as basic principles of welfare. Overall score (0-100 points) enabled finally categorization of farms into one of four welfare category (not classified, acceptable, enhanced and excellent).Based on results, half of the farms were assigned to acceptable, and other half to enhanced welfare category. Housing conditions on the majority of farms (63%) were assessed as unacceptable (?20 points) due to poor hygiene and discomfort. Cows were kept tied continuously on more than one third of farms which together with lack of pasture (17 days/year on average) restricting their comfort and freedom of movement. This may be also linked to low scored behavioral insurance (32points), especially inability to express its natural forms (6.7 points).Health condition was estimated as acceptable, but endangered welfare by high incidence of laminitis (38%), distocya (4.2%) and mortality (6.7%). Commonly performed dehorning procedure (79%) without anesthetic/analgesic application caused pain and stress in affected animals. Overall assessment score (2.5/5) showed the need for improvement in all areas of dairy cows' welfare, especially in terms of their housing and management.
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Cooper, M. D., D. R. Arney, and C. J. C. Phillips. "Differences in the behaviour of high and low yielding dairy cows selected by genetic merit." Proceedings of the British Society of Animal Science 2002 (2002): 220. http://dx.doi.org/10.1017/s1752756200008760.
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The effects of high milk yields on the behaviour and welfare of the dairy cow are unclear. A high milk yield increases the need to consume sufficient fodder in an attempt to meet high nutrient demands. The failure to meet the demands may result in persistent hunger in the dairy cow having to modify her behaviour by employing various coping strategies. These modifications may help the cow overcome a state of hunger but at the expense of being unable to express other important behaviours. The objective of this study was therefore to determine whether the behaviour and welfare of the genetically high yielding dairy cow is being compromised by the increased nutritional demands of milk production, and to investigate the possibility that an increased amount of time spent in food-directed behaviours may have a detrimental effect on the time available to perform other important behaviours.
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Moser, Scott A., and Dwayne C. Savage. "Bile Salt Hydrolase Activity and Resistance to Toxicity of Conjugated Bile Salts Are Unrelated Properties in Lactobacilli." Applied and Environmental Microbiology 67, no. 8 (August 1, 2001): 3476–80. http://dx.doi.org/10.1128/aem.67.8.3476-3480.2001.
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ABSTRACT Bacteria of numerous species isolated from the human gastrointestinal tract express bile salt hydrolase (BSH) activity. How this activity contributes to functions of the microorganisms in the gastrointestinal tract is not known. We tested the hypothesis that a BSH protects the cells that produce it from the toxicity of conjugated bile salts. Forty-nine strains of numerous Lactobacillusspp. were assayed to determine their capacities to express BSH activities (taurodeoxycholic acid [TDCA] hydrolase and taurocholic acid [TCA] hydrolase activities) and their capacities to resist the toxicity of a conjugated bile acid (TDCA). Thirty of these strains had been isolated from the human intestine, 15 had been recovered from dairy products, and 4 had originated from other sources. Twenty-six of the strains expressed both TDCA hydrolase and TCA hydrolase activities. One strain that expressed TDCA hydrolase activity did not express TCA hydrolase activity. Conversely, in one strain for which the assay for TDCA hydrolase activity gave a negative result there was evidence of TCA hydrolase activity. Twenty-five of the strains were found to resist the toxicity of TDCA. Fourteen of these strains were of human origin, nine were from dairy products, and two were from other sources. Of the 26 strains expressing both TDCA hydrolase and TCA hydrolase activities, 15 were resistant to TDCA toxicity, 6 were susceptible, and 5 gave inconclusive results. Of the 17 strains that gave negative results for either of the enzymes, 7 were resistant to the toxicity, 9 were susceptible, and 1 gave inconclusive results. These findings do not support the hypothesis tested. They suggest, however, that BSH activity is important at some level for lactobacillus colonization of the human intestine.
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Ozoliņš, Jānis. "Effect of Integration on the Gross Value Added in the Baltic States Dairy Sector Secondary Level." Proceedings of the Latvia University of Agriculture 28, no. 1 (February 6, 2013): 20–28. http://dx.doi.org/10.2478/v10236-012-0011-4.
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Abstract Dairy sector is an essential part of Baltic States economies in terms of created gross value added (GVA) and labour usage. The dairy sector’s potential to create economic effect is underutilised as a result of fragmented production structure and ensuing low economic efficiency. Integration can facilitate concentration of the sector’s market structure. The aim of this paper is to evaluate the effect of dairy sector secondary-level company integration on the creation of GVA. To accomplish the aim, an extensive sample of 54 companies is used whereas previous research has been based on data of only 5-10 largest Baltic States companies. It is concluded that integration characteristics of dairy processing companies significantly influence relationships which express their GVA creation pattern. Dominating horizontally integrated dairy processing companies are the most valuable to the economy as their GVA increase rate which results from net turnover growth is the highest. Non-integrated companies’ GVA growth rate provided that their net turnover grows is lower than for dominating horizontally integrated companies. Increases in company size do not statistically significantly increase the relation of GVA to the sum of net turnover and other operating income. Both successful and commercially weak companies can produce high GVA in respect to their size. However, only the successful companies are expected to generate positive growth dynamics, be economically efficient and can be relied upon as driving force of dairy sector growth.
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STELLA, A. E., R. P. MALUTA, E. C. RIGOBELO, J. M. MARIN, and F. A. DEÁVILA. "Virulence Genes in Isolates of Escherichia coli from Samples of Milk and Feces from Dairy Cattle." Journal of Food Protection 75, no. 9 (September 1, 2012): 1698–700. http://dx.doi.org/10.4315/0362-028x.jfp-11-468.
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The aim of this work was to determine if Escherichia coli isolates carrying the virulence genes eae and eltB and exhibiting the Ehly phenotype are present in feces and milk samples from healthy dairy cattle on farms. Isolates from calves showed a statistically higher prevalence of eae and eltB compared with isolates from older animals. The other factors tested (stx1, stx2, and Ehly) were not statistically different between the two groups. Two isolates originating from calf feces were identified as serotype O157:H7; one of these isolates carried stx1 and eae, the other stx2 and eae. E. coli isolated from milk contained stx1, stx2, and eltB. The results show that feces or milk from healthy dairy cattle may contain E. coli pathotypes that express virulence genes, indicating that these materials have zoonotic potential. The results also reinforce the idea that host age can influence the dynamics of virulence genes in E. coli from cattle.
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Glavić, Midhat, Amir Hasić, Amir Zenunović, and Vehid Mahmutović. "Protection and Animal Welfare in Farming Practices for Milk Production in Region of Northeastern Bosnia and Herzegovina." АГРОЗНАЊЕ 14, no. 4 (December 27, 2013): 479. http://dx.doi.org/10.7251/agren1304479g.
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The main goal of the research is to determine the conditions of welfare and housing of farm animals for milk production. Milk producers in the region of northeastern BiH are not informed enough about the protection and welfare of animals. This research was conducted in May 2012. The results were obtained on the basis of the questionnaire methodology in five freedoms in the welfare and accommodation of animals (Webster, 1987). Farms are divided into three groups, farms that have up to 5 dairy cows (they are in majority in the region), farms that have up to 20 dairy cows and farms with more than 20 dairy cows. On farms that have up to 5 dairy cows all farms posses tied system of keeping cows and cows are kept in closed conditions. Farms with up to 20 dairy cows also a large percentage of 67% related to the system of keeping cows in indoor conditions. A smaller part of the farm has a free system of keeping cows and stables open with good light and ventilation. Only 16% of farms with more than 20 dairy cows are tied housing system and the rest of the free system of keeping cows. All farms meet freedom from hunger and thirst, but the big problem is freedom from discomfort, freedom from stress and fear, freedom of injury and illness and the freedom to express natural behavior. The research was carried out within the project "Improvement of milk production in northeastern Bosnia and Herzegovina" funded by the Development Agency of the Czech Republic.
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Medrano-Galarza, Catalina, Stephen J. LeBlanc, Andria Jones-Bitton, Trevor J. DeVries, Jeffrey Rushen, Anne Marie de Passillé, and Derek B. Haley. "Producer perceptions of manual and automated milk feeding systems for dairy calves in Canada." Canadian Journal of Animal Science 98, no. 2 (June 1, 2018): 250–59. http://dx.doi.org/10.1139/cjas-2017-0038.
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As part of a cross-sectional survey, Canadian dairy producers were asked a set of questions to (1) determine factors that influenced them to continue using manual milk feeding (MMF) systems or to switch to automated milk feeding (AMF) and (2) investigate producers’ perceived advantages and disadvantages regarding both feeding systems. A total of 670 responses were received. Among respondents, 16% used AMF and 84% used MMF. The four most frequent factors that producers reported as important in motivating them to switch to AMF were to raise better calves, offer more milk to calves, reduce labor, and improve working conditions. For MMF farms, investment in equipment and group housing facilities, as well as farm size, were the primary reasons reported for their continued use of MMF systems. The principal perceived advantages of having an AMF were that calves are able to express natural behaviors and drink more milk without increased labor input. For MMF systems, the main perceived advantage was related to easier identification of sick calves. Results provide insights into factors affecting the choice of calf feeding methods by dairy producers, and improve understanding of producers’ needs and expectations regarding calf management and adoption of technology.
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Wicks, H. C. F., and J. D. Leaver. "Influence of Genetic Merit on 305-day Milk Production of Dairy Cattle on Commercial Farms at Three Levels of Feeding." Proceedings of the British Society of Animal Science 2002 (2002): 14. http://dx.doi.org/10.1017/s1752756200006700.
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The objective was to estimate the influence of genetic merit on milk production at different levels of concentrate feeding. The presence of an interaction between genetic merit and level of feeding would mean that cows with a high potential for milk production are unable to express their potential under all conditions. Oldham and Simm, (1998) showed there was a significant interaction between level of concentrate feeding and PTAf+p under experimental conditions, and that the milk yield response to genetic merit increased with increased concentrate feeding. The current work estimated the value of genetic merit (PIN95 and PTAf+p) on 305-day milk production traits of dairy cattle on commercial farms, where farms were categorised by the level of concentrate (Cg) fed.
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Perier, Nadège, Alice de Boyer des Roches, Margit Bak Jensen, and Kathryn Proudfoot. "Infectious Disease Does Not Impact the Lying and Grooming Behaviour of Post-Parturient Dairy Cows." Animals 9, no. 9 (August 30, 2019): 634. http://dx.doi.org/10.3390/ani9090634.
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Behaviour is commonly used to detect sickness in animals, but the impact of sickness on lying and maternal behaviours around parturition is not well understood. The objective was to assess the effects of sickness on the lying and grooming behaviours of dairy cows in the first 24 h after giving birth. Cows were categorized as ‘sick’ (n = 8) if they had at least one rectal temperature ≥39.1 °C and one clinical sign of illness (mastitis, pneumonia or an unknown infection) within 24 h of calving. These cows were match-paired for parity with cows that had no rectal temperature ≥39.1 °C and no clinical signs of illness up to 3 d after calving (n = 8; ‘not sick’). The duration and latency of cow behaviours (standing, lying, lying bouts, lying close to calf, and grooming of the calf) and calf behaviours (standing and lying) were recorded for 24 h post-partum. We found no differences in the behaviour of sick and not sick cows and their calves post-calving, except that sick cows took longer to lie down near their calf after calving compared to those without illness. Cows may be more motivated to groom and spend time with their calf than to express sickness behaviours immediately after giving birth.
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Orden, José Antonio, José Antonio Ruiz-Santa-Quiteria, Silvia García, Dolores Cid, and Ricardo de la Fuente. "In Vitro Activities of Cephalosporins and Quinolones against Escherichia coli Strains Isolated from Diarrheic Dairy Calves." Antimicrobial Agents and Chemotherapy 43, no. 3 (March 1, 1999): 510–13. http://dx.doi.org/10.1128/aac.43.3.510.
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ABSTRACT The in vitro activities of several cephalosporins and quinolones against 195 strains of Escherichia coli isolated from dairy calves affected by neonatal diarrhea were determined. One hundred thirty-seven of these strains produced one or more potential virulence factors (F5, F41, F17, cytotoxic necrotizing factor, verotoxin, and theeae gene), but the remaining 58 strains did not produce any of these factors. From 11 to 18% of the E. coli strains were resistant to cephalothin, nalidixic acid, enoxacin, and enrofloxacin. However, cefuroxime, cefotaxime, and cefquinome were highly effective against the E. coli isolates tested. Some significant differences (P < 0.05) in resistance to quinolones between the strains producing potential virulence factors and nonfimbriated, nontoxigenic, eae-negative strains were found. Thus, eae-positive, necrotoxigenic, and verotoxigenic (except for nalidixic acid) E. coli strains were significantly more sensitive to nalidixic acid, enoxacin, and enrofloxacin than nonfimbriated, nontoxigenic, eae-negative strains. Moreover, eae-positive strains were significantly more sensitive to enoxacin and enrofloxacin than F5-positive strains. Thus, the results of this study suggest that the bovine E. coli strains that produce some potential virulence factors are more sensitive to quinolones than those that do not express these factors.
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Riboni, Mario Vailati, John Roche, Ilkyu Yoon, and Juan Loor. "Nutrition as a way to improve the dairy industry sustainability: a nutrigenomic approach." Journal of Animal Science 97, Supplement_2 (July 2019): 29–30. http://dx.doi.org/10.1093/jas/skz122.054.
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Abstract Due to the high incidence of diseases and high culling rate, the peripartum is a period of significant stress, and its management sets the stage for the health, future productivity and reproductive performance of the herd, hence making it the perfect target to improve the industry sustainability as a whole. Looking at grazing systems, using a nutrigenomic approach, we determined that, contrary to historic industry standards, cows should be slightly underfed (~75% of their energy requirements) in the three weeks before parturition to prime their metabolism and ensure an optimal transition. Farmer will be able to preserve pasture area in a period of low forage production, reaching the spring (calving season) with abundant and high quality pasture. While looking at confined systems we tested the supplementation efficacy of immunomodulatory nutrients. The greater feed intake and greater milk production performances (both in milk quantity, and quality), coupled with lower incidence of disease, underscore a smoother transition to lactation when cows are supplemented with rumen-protected methionine. Moreover, methionine induced greater blood neutrophil phagocytosis and oxidative burst postpartum, and optimized the response to LPS, by mitigating the hyper-response of the immune cells. Supplementation of cows undergoing a mastitic challenge with a S. cerevisiae fermentation product improved indexes of mammary gland health and pathogen resistance. Pathway analysis highlighted physiological mechanisms enhancing local immune cell trafficking, antimicrobial activity, and inflammation control in the mammary gland of supplemented animals, compared to control cows that showed signs of tissue damage and loss of epithelial integrity. Looking at calf nutrition, enhancing nutrient intake in the pre-weaning period stimulates mammary development, increasing their future productivity potential. Nutritional improvement of animal health shows great potential as a rapidly applicable strategy to improve animal welfare, allowing them to express their full genetic potential.
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KIRSANOV, VLADIMIR V. "STRUCTURAL-AND-FUNCTIONAL MODELS FOR CONSTRUCTING DIGITAL TECHNOLOGICAL MODULES OF MODERN DAIRY FARMS." Agricultural engineering, no. 2 (2021): 32–38. http://dx.doi.org/10.26897/2687-1149-2021-2-32-38.
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Establishing a standard series of digital automated robotic dairy farms of a new generation with diff erent confi gurations and capacity (25-50-100…1200…2400 goals) implies their structural typing and modular building based on the methodology of fi nite element analysis and structural-functional models, including complete modular units. The author has developed structural and functional models for building digital technological modules and modular units of modern automated and robotic dairy farms of a new generation. Modular structural and functional units are proposed. They include passive accumulative and regulating modules of inanimate (material, technological) and animate biological fl ows (animals), active machine-technological modules for moving and transforming material technological and production fl ows to/from animals,information and analytical modules for rapid assessment of the quality of production fl ows, systems for receiving, transmitting, processing and storing information fl ows (signals) received from machine-technological modules (milking, feeding, manure removal, etc.) and from animal sensors. The author analyzed and obtained formalized structural and functional models of digital modular units: automated and robotic milking parlors, automated and robotic animal feeding systems, automated systems for diff erentiated microclimate provision, energy-saving aerobic and (or anaerobic) modules for manure processing as complete structures, including space-planning accumulative-regulating technological modules of the passive type and machine-technological modules of the active type to move and transform material technological fl ows, as well as carry out express diagnostics of their quality and storage of information fl ows. The implementation of the developed structural and functional models of digital technological modules and modular units will provide for designing new projects of digital automated and robotic dairy farms of a new generation with increased functionality and adaptive functions to be applied to biological objects.
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Guo, Yuru. "Antimicrobial Resistance and Virulence Genes Distribution in Trueperella pyogenes Isolated from Dairy Cows with Clinical Mastitis in Liaoning of China." Pakistan Veterinary Journal 41, no. 03 (August 1, 2021): 329–34. http://dx.doi.org/10.29261/pakvetj/2021.040.
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Trueperella pyogenes is considered as a causative agent of many infections, such as mastitis, endometritis, pneumonia, liver abscessation. T. pyogenes can express several virulence genes such as plo, fimA, cbpA, nanH and nanP contributing to its pathogenicity. The aim of this study was to provide an investigation about antimicrobial resistance, as well as virulence genes distribution and gene cassettes among T. pyogenes isolates from dairy cows with clinical mastitis. The susceptibility to different antimicrobial agents was determined by the Broth Microdilution Method, and virulence genes and gene cassette was detected by polymerase chain reactions (PCRs). There are 10.49% (17/162) of milk samples from dairy cows with mastitis were positive for T. pyogenes. High levels of resistance were found to clindamycin (23.53%), oxytetracycline (23.53%), ciprofloxacin (47.06%), sulfamethoxazole/trimethoprim (100%). Moreover, all isolates carried class I integrons, and gene cassette arrays were aadA9 (2/17) or aadA5-dfrA17 (3/17). Finally, all isolates harbored plo nanH and fimA genes, but other genes encoding virulence genes including fimC, fimE, nanP and cbpA are ranged from 47.06% to 88.23%. Our study showed T. pyogenes isolates from dairy cows with clinical mastitis were susceptible to β-lactams. In addition, all seven virulence genes occurred in isolates, and plo, nanH, and fimA gene showed a significantly higher frequency in T. pyogenes of the Liaoning Province, China.
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Pilz, M., C. Fischer-Tenhagen, M. Grau, and W. Heuwieser. "Behavioural and physiological assessment of stress reactions during vaginal examination in dairy cows." Tierärztliche Praxis Ausgabe G: Großtiere / Nutztiere 42, no. 02 (2014): 88–94. http://dx.doi.org/10.1055/s-0038-1623211.
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Summary Objectives and aim: The objective of this study was to determine the origin of an arched back in cows during vaginal examination. Moreover, we tested whether the duration of an arched back and avoidance reactions during vaginal examination can be decreased by epidural anaesthesia or analgesic treatment. Material and methods: Behaviour during cleaning of the perivaginal region and during vaginal examination was scored using the avoidance reactivity score (ARS). Heart rate (HR) was recorded in 10 dairy cows considering four experimental phases, i.e. baseline, cleaning the perivaginal region, vaginal examination and post-examination. Each cow was examined three times and received no treatment (CON), an epidural anaesthesia (EPID) or an analgesic treatment (NSAID). The duration of an arched back during and post-examination was measured. Results: The expression of the arched back was shortest in cows of group EPID and longest in cows of group CON. Avoidance reactions did not differ between the cleaning phase and vaginal examination in cows of group EPID. Cows of group CON showed the strongest avoidance reactions during examination, whereas cows of group EPID showed least avoidance reactions. Mean HR increased during cleaning and vaginal examination and decreased post-examination. Mean HR during vaginal examination did not differ between treatment groups. Conclusion: The results show that cows express discomfort during vaginal examination with an increase in avoidance reactions and HR. Although epidural anaesthesia could reduce sensitivity in the perivaginal region, cows still felt the urge to empty the vagina from the examiner’s hand and, thus, were arching their back. Clinical relevance: In practice, routine vaginal examinations in dairy cows have not been considered as invasive examinations. Our results show that vaginal examinations indeed do cause discomfort. We do not suggest the application of any anaesthetic treatment as appropriate before routine vaginal examinations. None theless, the examiner should be aware of the stress potential of vaginal examinations and conduct such examinations most carefully.
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French, P., K. O. Driscoll, B. Horan, and L. Shalloo. "The economic, environmental and welfare implications of alternative systems of accommodating dairy cows during the winter months." Animal Production Science 55, no. 7 (2015): 838. http://dx.doi.org/10.1071/an14895.
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Pasture grazed in situ is one of the most competitive and sustainable feeding systems for dairy cows globally because of a low environmental footprint, the potential for excellent animal welfare and the relatively low cost in the production and utilisation of the feed. However, because of seasonal variation in grass production and inclement weather conditions, dairy cattle may have to be accommodated and/or fed off pasture. There are numerous infrastructural options for achieving this and the focus of the present paper was to review the research and discuss the merits of these alternate animal accommodation systems, focussing on the impact that they have on the environment, animal welfare and farm profitability relative to pasture-only systems. Research data showed that dairy cow welfare can be protected in a range of well managed alternative winter accommodation. In a temperate climate, such as that which pertains in Ireland, adequately fed adult cattle will not use extra feed energy to maintain body temperature when accommodated outdoors and exposed to the effects of wind, rain and low temperatures, as the heat produced from the digestion of feed is in excess of the requirement to maintain body temperature. The main welfare challenge of a wintering system in such conditions is to provide suitable lying facilities for cows to express normal lying behaviour and provide adequate feed. The primary economic focus of pasture-based systems should be to maximise the length of the grass-grazing season and, consequently, to minimise the period off paddock. Provided that body condition targets can be met, there will be minimal effect of wintering system on dairy cow productivity and the only economic differences will be in costs. The cost analysis should combine the capital costs of construction financed over its useful life and the annual operating costs, including labour.
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Mayne, C. S., and F. J. Gordon. "Implications of genotype X nutrition interactions for efficiency of milk production systems." BSAP Occasional Publication 19 (1995): 67–77. http://dx.doi.org/10.1017/s0263967x00031815.
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AbstractMajor increases in the rate of genetic improvement in the dairy herd have been obtained in the United Kingdom and the Republic of Ireland since the mid 1980s. The implications of increases in genetic merit and the possible consequences of genotype X nutrition interactions on the efficiency of milk production systems are reviewed. The majority of previous studies with dairy cattle of moderate genetic merit suggest little evidence of genotype X nutrition interactions across a range of nutritional and management regimes, with higher milk production of high merit cows largely accounted for by effects on nutrient partitioning. However, more recent results suggest a significant re-ranking of sires when evaluated under either intensive feeding systems or in systems with a high reliance on grazed pasture.Under intensive feeding systems higher animal performance has been obtained with high merit cows across a range of concentrate inputs and feeding systems. However, recent results from the Langhill studies provide the first tentative evidence of a genotype X nutrition interaction, with significantly different regression coefficients between genetic merit (as assessed by pedigree index) and milk production, under either low or high forage diets. The implications of these results are that high merit cows may be unable to express their full genetic potential for milk production when offered a high forage (or low energy density) diet. Consequently, the influence of other factors which have a major effect on voluntary food intake, and hence nutrient intake, e.g. forage dry matter content and forage digestibility, may be relatively more important with high genetic merit dairy cows.It is concluded that higher milk production in high merit cows is largely attributable to variation in partitioning of nutrients, rather than to changes in food intake or digestive efficiency. Consequently, it is important fully to assess the animal performance and welfare implications of maintaining high genetic merit dairy cows under systems which may limit nutrient intake, e.g. under high forage regimes involving a high reliance on grazed or conserved forage. The major challenge for research and dairy herd management is to increase food intake with grass- and/or grass silage-based diets, thereby reducing the need for high levels of concentrates input to prevent excessive body condition loss with high genetic merit dairy cows in early lactation.
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Leshonok, O., and V. Gridin. "Performance profile of cows of ural type at different level of milk productivity." Glavnyj zootehnik (Head of Animal Breeding), no. 2 (February 1, 2020): 22–28. http://dx.doi.org/10.33920/sel-03-2002-03.
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One of the tasks of selection and breeding work with dairy cattle is to assess the body type of cows in breeding herds. Body type plays an important role in the effi ciency of the use of animals in dairy cattle breeding only harmoniously developed cows when creating optimal conditions for housing and feeding, can show high milk productivity as well as they are less prone to the risks of premature culling for non-selective reasons. The selection of fi rst-calf heifers of Ural type of Black-and-White breed with milk productivity above 7000 kg of milk in breeding organizations of the Sverdlovsk region has been carried out. Materials on 2150 cows with average milk yield of 8622 kg of milk with the content of fat in milk of 3,90 % and protein – 3,20 % have been presented. With an increase in milk yield in fi rst-calf heifers there is a statistically signifi cant improvement in constitutional and performance features. Heifers have good parameters for the development of the body in height, which vary from 7,7 to 8,5 points, strong enough and deep body (fortress: 4,7–5,3 points; depth: 5,7–7,5 points), with well-defi ned milk forms (5,4–6,8 points). The udder of animals is characterized by a bath-shaped form (attachment density: 5,1–5,3 points; length of the front parts: 5,1–6,3 points) and an expressed escutcheon (width: 5,0–6,0 points; height: 7,8–8,3 points; central ligament: 4,9–5,3 points). For obtaining animals of dairy direction productivity with milk yield 7000 kg milk and more should make selection on the next parts of performance: rump high ≥ 7,0 points (from 145 centimeters); the depth of breast ≥ 6,0 points (not less 83 centimeters), length front share udder ≥ 5,0 points (from 21 centimeters), width rear share udder ≥ 5,0 points (not less 16 centimeters), express of dairy forms, central ligament ≥ 5,0 points.
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El-Sayed, G., Mohamed El-Diasty, and Hadeer Magdy. "Effect of progesterone on some reproductive performances in cattle." Mansoura Veterinary Medical Journal 20, no. 2 (June 25, 2019): 86–91. http://dx.doi.org/10.35943/mvmj.2019.22.109.
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Our experiment was conducted at a special dairy farm in Dakahlia Governorate between the periods (March –May 2018), This farm consisted of 400 Holestien cows; from the total of the animals only 210 lactating cows. The established experiment applied on 40 cows suffered from different types of anestrum detected by ultrasonography as follow (15 cows suffer from cystic ovary, 15 cows suffer from smooth inactive ovaries and 10 cows suffer from persist corpus luteum to study the effect of progesterone device insertion in dairy cattle and its effect in fertility. On day 0, cattle at random stage of estrous cycle received controlled internal drug release vaginal insert (CIDR).We left the CIDR in the vagina for seven days as we inject PGF2 on day 6 and remove the CIDR on day 7, blood samples were collected from 25 animals at zero day, 3rd, 7th and 9th day from the tail vein, and then we follow the estrous and detected the estrus cow for AI and apply ultrasonography for pregnancy diagnosis after 30 day from insemination From this study it was concluded that the use of progesterone for 7 days +i.m. injection of PGF2α in the 7th day can applied to dairy cattle to restart ovarian activity and it is an effective treatment for different infertility cases like cystic ovarian disease, persist corpus luteum and smooth in active ovaries. Moreover present study provides evidence for the importance of prior exposure to progesterone for cows to express estrous behavior, increase number of pregnant animals and increase conception rate.
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Raftari, Mohammad, Sobhan Ghafourian, and Fatimah Abu Bakar. "Metabolic engineering ofLactococcus lactisinfluence of the overproduction of lipase enzyme." Journal of Dairy Research 80, no. 4 (September 24, 2013): 490–95. http://dx.doi.org/10.1017/s0022029913000435.
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The dairy industry uses lipase extensively for hydrolysis of milk fat. Lipase is used in the modification of the fatty acid chain length, to enhance the flavours of various chesses. Therefore finding the unlimited source of lipase is a concern of dairy industry. Due to the importance of lipase, this study was an attempt to express the lipase fromBurkholderia cepaciainLactococcus lactis.To achieve this, a gene associated with lipase transport was amplified and subcloned in inducible pNZ8148 vector, and subsequently transformed intoLc. lactisNZ9000. The enzyme assay as well as SDS-PAGE and western blotting were carried out to analysis the recombinant lipase expression. Nucleotide sequencing of the DNA insert from the clone revealed that the lipase activity corresponded to an open reading frame consisting of 1092 bp coding for a 37·5-kDa size protein. Blue colour colonies on nile blue sulphate agar and sharp band on 37·5-kD size on SDS-PAGE and western blotting results confirm the successful expression of lipase byLc. lactis. The protein assay also showed high expression, approximately 152·2 μg/ml.h, of lipase by recombinantLc. lactis.The results indicate thatLc. lactishas high potential to overproduce the recombinant lipase which can be used commercially for industrially purposes.
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Whalin, Laura, Daniel M. Weary, and Marina A. G. von Keyserlingk. "Understanding Behavioural Development of Calves in Natural Settings to Inform Calf Management." Animals 11, no. 8 (August 20, 2021): 2446. http://dx.doi.org/10.3390/ani11082446.
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One important type of animal welfare concern is “natural living” (i.e., that animals are able to express natural behaviours that are important to them, and to engage with aspects of the natural world that they find important). The aims of this narrative review were to describe the behavioural development of calves (Bos taurus) in natural settings and use this to identify characteristics of natural systems that may be important to consider relative to this natural living conception of animal welfare. At birth, calves are licked by their mothers and soon stand to suckle for colostrum, and during the milk-feeding period, calves spend much of their time lying down. In natural systems, calves perform a variety of social behaviours with herd-mates, and slowly transition from their mother’s milk to eating solid food, by gradually increasing time spent grazing and ruminating. In contrast, on most commercial dairy systems, dairy calves are removed from their mothers at birth, housed individually, fed restricted amounts of milk and weaned abruptly at a young age. The results of this review suggest that accommodating key natural behaviours, for example through the use of teat feeding of milk, social housing, and gradual weaning, can help address welfare concerns.
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Biala, J., N. Lovrick, D. Rowlings, and P. Grace. "Greenhouse-gas emissions from stockpiled and composted dairy-manure residues and consideration of associated emission factors." Animal Production Science 56, no. 9 (2016): 1432. http://dx.doi.org/10.1071/an16009.
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Emissions from stockpiled pond sludge and yard scrapings were compared with composted dairy-manure residues blended with shredded vegetation residues and chicken litter over a 5-month period at a farm in Victoria (Australia). Results showed that methane emissions occurred primarily during the first 30–60 days of stockpiling and composting, with daily emission rates being highest for stockpiled pond sludge. Cumulated methane (CH4) emissions per tonne wet feedstock were highest for stockpiling of pond sludge (969 g CH4/t), followed by composting (682 g CH4/t) and stockpiling of yard scrapings (120 g CH4/t). Sizeable nitrous oxide (N2O) fluxes were observed only when temperatures inside the compost windrow fell below ~45−50°C. Cumulated N2O emissions were highest for composting (159 g N2O/t), followed by stockpiling of pond sludge (103 g N2O/t) and yard scrapings (45 g N2O/t). Adding chicken litter and lime to dairy-manure residues resulted in a very low carbon-to-nitrogen ratio (13 : 1) of the composting mix, and would have brought about significant N2O losses during composting. These field observations suggested that decisions at composting operations, as in many other businesses, are driven more by practical and economic considerations rather than efforts to minimise greenhouse-gas emissions. Total greenhouse-gas emissions (CH4 + N2O), expressed as CO2-e per tonne wet feedstock, were highest for composting (64.4 kg), followed by those for stockpiling of pond sludge (54.5 kg) and yard scraping (16.3 kg). This meant that emissions for composting and stockpiling of pond sludge exceeded the new Australian default emission factors for ‘waste composting’ (49 kg). This paper proposes to express greenhouse-gas emissions from secondary manure-management systems (e.g. composting) also as emissions per tonne wet feedstock, so as to align them with the approach taken for ‘waste composting’ and to facilitate the development of emission-reduction methodologies for improved manure management at the farm level.
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Romanzin, Alberto, Mirco Corazzin, Edi Piasentier, and Stefano Bovolenta. "Effect of rearing system (mountain pasture vs. indoor) of Simmental cows on milk composition and Montasio cheese characteristics." Journal of Dairy Research 80, no. 4 (July 26, 2013): 390–99. http://dx.doi.org/10.1017/s0022029913000344.
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Dairy cattle in the Alps are traditionally maintained on high altitude pastures during summer. In recent decades, however, many farmers prefer to maintain the cows always indoor with a hay-based diet. Many authors have shown that the forage type is able to modify the characteristics of milk and cheese. Recently the product specification of PDO Montasio allowed differentiation between mountain cheeses and other products. Aim of this trial is to study the effect of rearing system on the characteristics of milk and cheese produced in this context. One hundred and twenty Simmental dairy cows were considered, 60 grazed on high altitude pasture, and 60 kept indoor and fed a hay-based diet. Cheese production was repeated in two periods (early July and late August) and ripened two and six months. Pasture-derived milk and cheese presented higher fat and lower protein content than hay-derived ones. Rearing systems also affected cheese colour. Textural parameters, hardness, gumminess and chewiness were found to be higher in pasture-derived cheese. In addition, it showed lower level of total saturated fatty acids, and higher level of mono and polyunsaturated fatty acids than hay-derived cheeses. Consumers perceived the difference of cheeses in terms of colour and holes, but they express a similar overall liking. More limited effects of period and ripening time were observed.
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Deng, Qinghua, Dehui Ma, Guoquan Sun, Xue Yuan, Zhe Wang, and Guowen Liu. "PTEN influences insulin and lipid metabolism in bovine hepatocytes in vitro." Journal of Dairy Research 86, no. 1 (February 2019): 73–76. http://dx.doi.org/10.1017/s0022029919000128.
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AbstractDairy cows with fatty liver or ketosis display decreased insulin sensitivity and defects in the insulin receptor substrate (IRS)/PI3K/AKT signaling pathway. Phosphatase and tensin homolog (PTEN) is a well-known tumor suppressor and also a negative regulator of insulin signaling and peripheral insulin sensitivity. We investigated the hypothesis that PTEN may affect the insulin pathway-mediated hepatic glucose and lipid metabolism in dairy cows. Adenovirus vectors that over-express and silence PTEN were constructed, and then transfected into hepatocytes isolated from calves to investigate the effect of PTEN on PI3K/AKT signaling pathway. PTEN silencing increased the phosphorylation of AKT and the expression of PI3K but decreased the phosphorylation of IRS1, which increased the phosphorylation levels of glycogen synthase kinase-3β (GSK-3β) and expression of sterol regulatory element-binding protein-1c (SREBP-1c). Increased GSK-3β phosphorylation further up-regulated expression of the key enzymes phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6-Pase) involved in gluconeogenesis. Furthermore, the expression of SREBP-1c target gene fatty acid synthase (FAS) also increased significantly. We further showed that PTEN over-expression could reverse the above results. PTEN negatively regulates the enzymes involved in hepatic gluconeogenesis and lipid synthesis, which suggests that PTEN may be a therapeutic target for ketosis and fatty liver in dairy cows.
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Ergul Ekiz, Elif, Hulya Yalcintan, and Bulent Ekiz. "Haematological stress parameters and behavioural characteristics of dairy type goat kids compared to indigenous breeds during an intensive fattening programme." Archives Animal Breeding 63, no. 2 (December 2, 2020): 441–49. http://dx.doi.org/10.5194/aab-63-441-2020.
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Abstract. In any production model, the extent to which the animals cope with the environment is important in terms of animal welfare and sustainability of production. The aim of the study was to investigate certain haematological parameters and behaviours of goat kids from dairy type Saanen and Maltese breeds via comparison with indigenous Hair and Gokceada breeds during the 10-week intensive fattening period. Eleven male goat kids each of Saanen, Maltese, Hair and Gokceada breeds were weaned at 3–3.5 months of age and then placed into four fattening pens prepared for each breed, separately. Cortisol, glucose and total protein levels were higher in Gokceada kids in the last period of the fattening compared to the kids of other breeds (P<0.05). In Gokceada kids, an evident decrease in the time spent hay feeding and on rumination and an increase in lying, standing and self-grooming behaviours were determined during the last 3 weeks of fattening. Moreover, there was a significant decrease regarding hay feeding in Hair goat kids in the last 2 weeks (P<0.05). Hair goat kids also exhibited less rumination behaviour compared to Saanen kids during the last 4 weeks of fattening (P<0.05). On the other hand, kids of dairy breeds did not express behavioural or biochemical stress responses during the fattening period. As a conclusion, when evaluated in terms of animal welfare, results of the current study may indicate that indigenous breeds, especially Gokceada kids, are not appropriate for intensive fattening in a pen.
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Guzmán, Jennifer R., and Melanie A. Medeiros. "An Unlikely Cause: The Struggle for Driver's Licenses to Prevent Family Separation." Practicing Anthropology 41, no. 1 (January 1, 2019): 3–6. http://dx.doi.org/10.17730/0888-4552.41.1.3.
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Abstract As a result of the family separation policies that were implemented at the southern border of the United States this summer, public attention turned to draconian federal practices that criminalize, imprison, and harm unauthorized immigrants. In Upstate New York, by contrast, the immigrant rights movement is focused on a state level policy that would protect immigrant families from the separations that occur when immigrants who lack a driver's license are turned over by state and local law enforcement to federal immigration authorities. This article highlights the reasons why one grassroots organization of Latin American dairy farmworkers is campaigning for a humane driver's license policy and why they see this as the best route to protect against family separations. We highlight the motivations members of the group express and discuss how our research and advocacy with this organization follows a model of engaged anthropology in which directly-affected people take the lead.
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Piton, Christine, and Rémy Grappin. "A Model for Statistical Evaluation of Precision Parameters of Microbiological Methods: Application to Dry Rehydratable Film Methods and IDF Reference Methods for Enumeration of Total Aerobic Mesophilic Flora and Coliforms in Raw Milk." Journal of AOAC INTERNATIONAL 74, no. 1 (January 1, 1991): 92–103. http://dx.doi.org/10.1093/jaoac/74.1.92.
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Abstract A new statistical approach for collaborative study data of microbiological methods Is proposed. This Includes a confirmatory test to the Polsson distribution of the number of colonies. In addition, 2 new statistical parameters are used to express precision as a percent of the original unit: the geometric relative standard deviation (GRSD) and the critical relative difference between 2 measurements (RD95). This statistical approach was applied to an Interlaboratory study to assess and compare the precision of both dry rehydratable film (PetrlfUrn® SM and Petrifllm® VRB) methods and International Dairy Federation (IDF) reference methods [total aerobic mesophilic plate count (TAMPC) and violet red bile lactose agar (VRBL) methods] for estimation of total bacteria and collform, respectively, in raw milk. Each of the 14 laboratories In the study analyzed 40 laboratory samples (20 different materials In blind duplicates) for total bacteria and collform counts by both the Petrifllm and standard methods. Repeatability standard deviations (In log10 unit) of TAMPC, Petrifllm SM, VRBL, and Petrifllm VRB were 0.106, 0.089, 0.219, and 0.171, respectively; their reproducibility standard deviations were 0.170,0.167,0.348, and 0.199, respectively.
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Amadori, Massimo, and Chiara Spelta. "The Autumn Low Milk Yield Syndrome in High Genetic Merit Dairy Cattle: The Possible Role of a Dysregulated Innate Immune Response." Animals 11, no. 2 (February 3, 2021): 388. http://dx.doi.org/10.3390/ani11020388.
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The analysis of milk yield data shows that high genetic merit dairy cows do not express their full production potential in autumn. Therefore, we focused on metabolic stress and inflammatory response in the dry and peripartum periods as possible causes thereof. It was our understanding that some cows could not cope with the stress imposed by their physiological and productive status by means of adequate adaptation strategies. Accordingly, this study highlights the noxious factors with a potential to affect cows in the above transition period: hot summer climate, adverse genetic traits, poor coping with unfavorable environmental conditions, outright production diseases and consequences thereof. In particular, the detrimental effects in the dry period of overcrowding, photoperiod change and heat stress on mammary gland development and milk production are highlighted in the context of the autumn low milk yield syndrome. The latter could be largely accounted for by a “memory” effect on the innate immune system induced in summer by diverse stressors after dry-off, according to strong circumstantial and indirect experimental evidence. The “memory” effect is based on distinct epigenetic changes of innate immunity genes, as already shown in cases of bovine mastitis. Following a primary stimulation, the innate immune system would be able to achieve a state known as “trained immunity”, a sort of “education” which modifies the response to the same or similar stressors upon a subsequent exposure. In our scenario, the “education” of the innate immune system would induce a major shift in the metabolism of inflammatory cells following their reprogramming. This would entail a higher basal consumption of glucose, in competition with the need for the synthesis of milk. Also, there is strong evidence that the inflammatory response generated in the dry period leads to a notable reduction of dry matter intake after calving, and to a reduced efficiency of oxidative phosphorylation in mitochondria. On the whole, an effective control of the stressors in the dry period is badly needed for better disease control and optimal production levels in dairy cattle.
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Behluli, B., M. Jahnke, J. K. West, and C. R. Youngs. "99 BIRTH OF THE FIRST BOVINE EMBRYO TRANSFER CALF IN THE REPUBLIC OF KOSOVA." Reproduction, Fertility and Development 29, no. 1 (2017): 157. http://dx.doi.org/10.1071/rdv29n1ab99.
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The objective of this applied field study was to assess the feasibility of successfully performing bovine embryo transfer in the Republic of Kosova—a feat that had not yet been accomplished in this newly independent (2008) eastern European country. Three Holstein heifers at the Iowa State University dairy farm were superovulated with a conventional descending dose regimen of FSH (Folltropin). Approximately 12 and 24 h after the observed onset of oestrus, heifers were inseminated with semen from a single Red Holstein bull. Embryos were non-surgically collected and washed in accordance with IETS procedures for sanitary handling of embryos. Embryos were cryopreserved for subsequent direct transfer. After obtaining an import permit from the Kosovo Food and Veterinary Agency, embryos were approved for export to the Republic of Kosova by the US Department of Agriculture, Animal Plant Health Inspection Service. Embryos were shipped via an express courier service. A total of 19 embryos were received in the Republic of Kosova. Recipients were monitored for signs of naturally occurring oestrus, and immediately before transfer, embryos were thawed by holding in air for 3 to 5 s followed by placement into a 37°C water bath for 25 to 30 s. The first-ever bovine embryo transfer calf in the Republic of Kosova was born July 6, 2015. A total of 9 calves were born from the 19 embryos transferred (47.4% embryo survival rate). Results of this applied field study show that bovine embryo transfer is feasible in the Republic of Kosova. Embryo transfer will be used to improve the quality of dairy cattle genetics in the Republic of Kosova and to subsequently increase the national supply of milk, decrease dependence on milk imports, and increase food security of the nation.
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Zasiekin, D. A., A. G. Pushkova, and R. O. Dymko. "Research of acute toxicity and the effect of detergent-disinfectant “Argomol” on the culture of ciliates Tetrahymena pyriformis." Animal Biology 22, no. 4 (December 2020): 22–26. http://dx.doi.org/10.15407/animbiol22.04.022.
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Detergents and disinfectants for sanitation of milking equipment and dairy equipment must have a wide range of antimicrobial activity and provide a proper cleaning effect. At the same time, they must meet high standards of environmental safety and non-toxicity. The article presents data on the parameters of acute toxicity of the new detergent-disinfectant “Argomol”, based on lactic acid, “Katamine AB”, polyhexamethylene guanidine hydrochloride and colloidal silver solution, as well as the toxicity of the tool, which was determined using the express method of Tetrachymena pyriformis. The acute toxicity of the means and its working 0.5% solution in tentative and detailed experiments on white mice was determined and the median lethal dose (DL50) was determined by the method of G. Kerber. It was found that the DL50 of the means in white mice for intragastric administration when calculated by the method of G. Kerber is 4250 mg/kg body weight, and 0.5% of its solution — more than 11000 mg/kg body weight, i. e. according to SOU 85.2-37-736:2011 “Veterinary drugs. Determination of acute toxicity”, this indicates that the means belongs to the IV class of toxicity, which combines low-toxic substances. The results of research on the effect of the new detergent-disinfectant “Argomol” on the culture of ciliates Tetrahymena pyriformis are presented. It was found that the detergent-disinfectant “Argomol” in concentrations of 0.02–0.5% at exposures of 1–10 min did not show toxic effects on the ciliate Tetrahymena pyriformis. Toxicological studies on ciliates suggest that the detergent-disinfectant “Argomol”, when used in the recommended doses and exposures, can be used for sanitation of milking equipment and dairy equipment, as it is environmentally friendly and low-toxic.
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Chankeaw, W., S. Lignier, M. Raliou, T. Ntallaris, C. Richard, Y. Guo, O. Sandra, G. Andersson, P. Humblot, and G. Charpigny. "113 Specific Impacts of Mild Feed Restriction on Gene Expression of Endometrial Luminal, Glandular and Stromal Cells in Postpartum Dairy Cows." Reproduction, Fertility and Development 30, no. 1 (2018): 196. http://dx.doi.org/10.1071/rdv30n1ab113.
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Although numerous studies have examined global mRNA expression in the whole endometrium, very few studies aimed at characterising the global mRNA profile at specific cellular types within this tissue. In this study, we hypothesised that metabolic status during the postpartum period can affect specifically gene expression of endometrial luminal, glandular epithelial and stromal cells. To achieve this, endometrial biopsies were performed in 22 postpartum cows receiving either a control diet (n = 12, aiming for 35 kg/d of energy-corrected milk, ECM) or a mild restricted diet (n = 10, aiming for 25 kg/d of ECM). The diet affected the metabolic status of the cows as documented in Ntallaris et al. (2017 Theriogenology 90, 276-283). Three endometrial biopsies were collected for each cow between 12 and 15 days post-oestrus (oestrus was synchronized with CIDR and all cows had progesterone concentrations >5 ng mL−1 at time of biopsy). Biopsies were frozen in Optimal Cutting Temperature compound and then 10-µm sections were obtained by using cryostat. Slides were fixed in ethanol and stained using cresol violet. Luminal and glandular epithelial cells as well as stromal cells were harvested by laser capture microdissection using the PixCell II LCM System. Following capture, mRNA was extracted from each cellular types using the Arcturus PicoPure RNA Isolation (Thermo Fisher Scientific, Waltham, MA, USA). A genome-wide transcriptomic profile of endometrial cells from biopsies was generated with RNAseq. Samples were sequenced in 50-length paired. The average number of reads across all samples was near 100 million. Reads were mapped on the UMD3.1 assembly of the Bos taurus genome using Tophat. Quantification of gene expression has been performed using HTSeq with annotations from Ensembl. The comparisons of interest have been performed using DESEqn 2 (R package) with the statistical method proposed by Love et al. (2014 Genome Biol. 15, 550). With an adjusted P-value of 0.05, 8, 571, and 2658 genes were found significantly differentially expressed between animals fed with low or control diets for glandular, stromal, and luminal cells respectively. These results provide novel insights into mechanisms regulating endometrium physiology in postpartum dairy cows. The number of differentially expressed genes according to diet was much higher in luminal epithelial and stromal cells than in glandular cells providing evidence that these cells express differential responses to the metabolic environment to which they are exposed. Therefore, transcriptomic analyses based only on full tissue, as possibly biased by differences in cell numbers of different types could be not fully relevant. We acknowledge the financial support of ‘Prolific’ (EU grant KBBE; 31176) and RMUTSV (Thailand)
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Sobko, G. "INDICATORS OF PHAGOCYTOSIS OF GRANULOCYTES NEUTROPHILES IN COWS BLOOD SICK ON SUBCLINICAL FORM OF MASTITIS AND UNDER THE INFLUENCE OF PREPARATION «ANTYMAST»." Scientific Messenger of LNU of Veterinary Medicine and Biotechnologies 18, no. 3(71) (October 8, 2016): 244–47. http://dx.doi.org/10.15421/nvlvet7155.
Full textAbstract:
The article contains the results ofthe experimental researches of the influence of preparation «Antymast», is made from natural bee raw material, on the indicators of neutrophils granulocytes phagocytosis of cows blood, which have subclinical form of mastitis.The research was conducted during the spring period on two groups of cows of Black–Spotted Dairy breeds (2–3 lactation) 5 – 7 animals in each group.The cows before starting the investigations were diagnosed with the help of viscose metric express method for subclinical forms of mastitis: control group – clinically healthy animals, research group – with signs of subclinical mastitis.Cows from the research group were administered intracisternally with one injection of syringe tube (13 ml) three times at intervals of 24 hours of preparation «Antymast»in the affected udder quarters, half of the therapeutic dose was prophylactically injected into the healthy quarter of breast.It was established that in cows, sick on subclinical form of mastitis, was observed the activation of phagocytic activity of blood granulocytes neutrophils against decrease in phagocytic index (p < 0,05) and the number and increase (p < 0,05) spontaneous NBT test.Intracisternal introduction of preparation «Antymast» to sick cows contributed to the normalization of phagocytic activity of blood neutrophils and increase their absorption capacity and the reduction of NBT test (p < 0,05).
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Bydanova, V. V., and N. V. Grudina. "Determination of the concentration of high-molecular water-soluble polymer used in the development of a new type of feed additive." Rossiiskaia selskokhoziaistvennaia nauka, no. 6 (December 15, 2019): 58–60. http://dx.doi.org/10.31857/s2500-26272019658-60.
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High molecular weight water soluble nanoscale polymers (HWP) have different functional functions and different applications. For the first time in livestock, we applied GDP in feeding ruminants to increase their dairy and meat productivity. When developing an innovative feed additive based on nanosized anionic polymers, it is necessary to study their properties, for this purpose it is necessary to determine the presence of these polymers in aqueous solutions. Currently, there are several basic methods for determining the concentration of HWP in water. However, they have significant disadvantages, including complexity of execution, duration of the process, use of aggressive reagents, necessity to use expensive equipment. Our rapid method of quantifying anionic HWP is simple, accurate and inexpensive. The method is based on the flocculating properties of polymers. The method envisages preparation of basic and auxiliary solutions of golden ochre pigment and saturated solution of mixture of sodium and potassium chloride salts, determination of time of gold ochre pigment settling in idle test and in analysed solutions. Formulas for calculation of ochre sedimentation rate and polymer concentration are given. The method can be used in the concentration range of anionic polymers 0.0001 0.5 mg/ml. The express method is intended for specialists of chemical laboratories of industrial and agricultural enterprises, scientific and medical institutions.
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Mahmood, Zahed, Muazzama Zahid, Muhammad Jahangeer, Areej Riasat, Naveed Munir, and Muhammad Asad. "Probiotic as Immune Modulator; A New Trend in Medication." FRONTIERS IN CHEMICAL SCIENCES 1, no. 2 (December 31, 2020): 29–58. http://dx.doi.org/10.52700/fcs.v1i2.10.
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Probiotics are live microbes that confer beneficial health effects to the host when administered in sufficient amount. The dead bacteria may express the properties of probiotic components. The most common strains of probiotics are lactobacillus and Bifidobacterium, these are also present in functional food stuffs mostly in dairy and fermented foods. The use of probiotics based on the goal of producing food microbes that are healthy for intestine and food ingestion. Basically, the purpose of probiotics is to prevent from pathogens and maintain the proper gastrointestinal functions. The probiotics ameliorate many digestive disorders included, lactose intolerance, irritable bowel syndrome and antibiotic associated diarrhea. Probiotics also treat other diseases such as cardiovascular diseases, diabetes, obesity, liver diseases, cancer and in the treatment of HIV. The patients of HIV who are on antiretroviral therapy, they, may have dysbiosis of gut microbiom. The probiotics are useful for the prevention of immunological activity of gut. Probiotics have different mechanism of action such as colonization of perturbed microbes in intestine, pathogens exclusion competitively, mucin production cell adhesion, production of short chain fatty acids and immune system modulation mainly differentiate the T regs and increase the regulation of anti-inflammatory cytokines (IL-10) and growth factors.
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Hendriks, Stacey J., Daniel J. Donaghy, Lydia M. Cranston, Grant R. Edwards, and David F. Chapman. "Perennial ryegrass breeding and the scaling issue: a review of system experiments investigating milk production and profit differences among cultivars." Animal Production Science 57, no. 7 (2017): 1289. http://dx.doi.org/10.1071/an16524.
Full textAbstract:
Results of studies designed to determine whether or not differences measured among perennial ryegrass cultivars in small-plot studies translate into differences in milk production and profit in dairy whole-system studies were reviewed. Only three experiments were identified that met the criteria for fully self-contained systems repeated over multiple years required to account for annual feed supply–demand balance, its interaction with animal intake and production, and the influence of inter-annual climate variability on these processes. Collectively, these studies provide evidence of improvement in animal production, associated with genetic gains from ryegrass breeding, albeit through shifts in factors such as heading date (as it affects herbage quality and grazing efficiency) and host plant by endophyte interactions, rather than through gains in dry-matter yield. The latter remains unresolved, despite substantial evidence for gains from small-plot trials of dry-matter yield increases in the order of 0.5% per annum. These studies also highlighted the number of factors that have to be taken into account in the design and conduct of such studies, including gaining clarity about the size of the differences that can be expected and ensuring sufficient statistical power. Implementing objective management rules that allow cultivars to express their potential and capture differences through the grazing animal will ensure sufficient measurement intensity to enable differences (if observed) in milk production and profit to be explained. This should guard against confounding factors such as the differential effects of insect pests on plant performance, and consequent changes in pasture botanical composition mediated by ryegrass endophyte strains. Despite these difficulties, more experiments of this type are required to quantify and, ultimately, increase the value being delivered by ryegrass breeding to pasture-based dairy production systems in temperate regions. Therefore, there is a need for whole-system studies to be undertaken to provide valuable new information and give farmers the confidence to invest in the use of new cultivars.
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Hernandez, Laura L., Sean W. Limesand, Jayne L. Collier, Nelson D. Horseman, and Robert J. Collier. "The bovine mammary gland expresses multiple functional isoforms of serotonin receptors." Journal of Endocrinology 203, no. 1 (August 4, 2009): 123–31. http://dx.doi.org/10.1677/joe-09-0187.
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Recent studies in dairy cows have demonstrated that serotonergic ligands affect milk yield and composition. Correspondingly, serotonin (5-HT) has been demonstrated to be an important local regulator of lactational homeostasis and involution in mouse and human mammary cells. We determined the mRNA expression of bovine 5-HT receptor (HTR) subtypes in bovine mammary tissue (BMT) and used pharmacological agents to evaluate functional activities of 5-HT receptors. The mRNAs for five receptor isoforms (HTR1B, 2A, 2B, 4, and 7) were identified by conventional real-time (RT)-PCR, RT quantitative PCR, and in situ hybridization in BMT. In addition to luminal mammary epithelial cell expression, HTR4 was expressed in myoepithelium, and HTR1B, 2A, and 2B were expressed in small mammary blood vessels. Serotonin suppressed milk protein mRNA expression (α-lactalbumin and β-casein mRNA) in lactogen-treated primary bovine mammary epithelial cell (BMEC) cultures. To probe the functional activities of individual receptors, caspase-3 activity and expression of α-lactalbumin and β-casein were measured. Both SB22489 (1B antagonist) and ritanserin (2A antagonist) increased caspase-3 activity. Expression of α-lactalbumin and β-casein mRNA levels in BMEC were stimulated by low concentrations of SB224289, ritanserin, or pimozide. These results demonstrate that there are multiple 5-HT receptor isoforms in the bovine mammary gland, and point to profound differences between serotonergic systems of the bovine mammary gland and the human and mouse mammary glands. Whereas human and mouse mammary epithelial cells express predominately the protein for the 5-HT7 receptor, cow mammary epithelium expresses multiple receptors that have overlapping, but not identical, functional activities.
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Zainettinova, D. B., N. N. Muhamadieva, M. N. Julanov, V. Yu Stefanyk, V. V. Zaviruha, and I. A. Sarhambaeva. "The effectiveness of the treatment of cows with mastitis." Scientific Messenger of LNU of Veterinary Medicine and Biotechnologies 21, no. 94 (July 30, 2019): 78–81. http://dx.doi.org/10.32718/nvlvet9414.
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The main sector of agriculture in Kazakhstan, including the East Kazakhstan region is cattle breeding and, in particular, cattle breeding, which is determined by climatic and geographical conditions. However, successful reproduction and increase in livestock productivity is largely hampered by infertility and mastitis, and as a result they cause significant economic damage and reduce the reproduction rate and profitability of dairy cattle. Recently, the number of subclinical mastitis in cows has increased, which subsequently lead to profound morphological and functional changes in the mammary gland, a decrease in milk productivity and quality. Mastitis can be caused by various reasons, primarily poor or inadequate feeding, poor care, improper maintenance and use of animals, negligent attitudes towards organizing and conducting artificial insemination, due to various diseases of the genital organs, which appear most often during childbirth and the postpartum period. The quality control of the milk of cows was investigated by California test and DEDM (Device for Express Diagnostic of Mastitis). The express methods that we used allowed us to identify the subclinical and clinical forms of mastitis and timely treat it. Laboratory studies on the presence of somatic cells in milk were also conducted. After the detection of breast diseases, complex symptomatic treatment was performed. For the treatment of various forms of mastitis, drugs were used: mastiet forte - intracisternally for five days at a dose of 10 ml 2 times a day for five days in a row. Mastiet Forte has a high therapeutic efficacy in subclinical and clinical forms of cow mastitis. And the drug ketoprof has also been used. Ketoprof as an anti-inflammatory agent was used intramuscularly – 3 ml per 100 kg of animal weight 1 time per day for 3 days in a row. Klineksin 5%, as an antibacterial agent, was used intramuscularly at a dose of 1 ml per 50 kg of body weight 1 time per day for 3 days in a row. Antimicrobial agents and biologically active substances needed to be combined for successful therapy. Such biologically active substances include vitamin of Helsivit. They were used subcutaneously – 6 ml once.
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Paskar, N. A., E. N. Parizhskaya, O. P. Rotar, M. A. Boyarinova, A. M. Erina, А. S. Alieva, E. P. Kolesova, Е. V. Mogychaya, and A. O. Konradi. "The relationship of food behavior and vascular aging on the example of a population selection of residents of St. Petersburg." Translational Medicine 7, no. 4 (September 22, 2020): 12–20. http://dx.doi.org/10.18705/2311-4495-2020-7-4-12-20.
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Background. Diet and nutrition can favorably modulate arterial function during vascular aging, and therefore the search for their relationship is important.Objective. To study the relationship between eating behavior and markers of early vascular aging in patients with prehypertension and arterial hypertension.Design and methods. The respondents from the population sample of the epidemiological observational study ESSE-RF were questioned. 477 questionnaires were selected for further analysis of the respondents’ eating habits and the prevalence of early vascular aging among them. Inclusion criteria were age over 40 years to assess the risk of developing cardiovascular complications using the SCORE and ASCORE scales; lack of criteria for high and very high risk on the SCORE scale. A standard questionnaire was used, developed on the basis of adapted and validated international methods, with 12 modules. In the answers of the respondents, the amount and frequency of consumption of table salt, sugar, animal fats, meat and processed meat products, vegetables and fruits, poultry and fish were analyzed. The estimated vascular age of all respondents was assessed using the ASCORE scale.Results. In total, the responses on eating behavior were analyzed in 295 women and 182 men aged 40 to 65 years; the estimated vascular age (ASCORE) was 55.5 ± 9.6 years. For respondents with healthy vascular aging, compared to respondents with premature vascular aging, significantly less salt (57.2% versus 70.6%), sausages (44.1% versus 27%) and higher consumption of poultry meat are typical (44.1% versus 13.9%), dairy products (73.6% versus 41.4%) and fresh vegetables / fruits (88.2% versus 58%). The group of people with healthy vascular aging showed a higher level of daily consumption of sweets (55.9% versus 30.5%).Conclusion. Based on the results of a questionnaire survey of the population sample, it can be assumed that there is a connection between the peculiarities of the food pattern and vascular aging. Express assessment of eating behavior and calculation of vascular age can be used in outpatient practice for preventive counseling.
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Braw-Tal, R., and Z. Roth. "Gene expression for LH receptor, 17α-hydroxylase and StAR in the theca interna of preantral and early antral follicles in the bovine ovary." Reproduction 129, no. 4 (April 2005): 453–61. http://dx.doi.org/10.1530/rep.1.00464.
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The onset of gene expression for three proteins that play pivotal roles in theca interna function, namely the LH receptor (LH-R), cytochrome P450 17α-hydroxylase (17αOH) and the steroidogenic acute regulatory protein (StAR), was determined. Ovaries were obtained on day 9 of the oestrus cycle from mature synchronized dairy cows (n= 5) and gene expression in preantral and antral follicles up to 4 mm in diameter was evaluated byin situhybridization. LH-R and 17αOH mRNAs were observed first, in the theca interna of large preantral follicles (type 4), concurrent with its morphological differentiation. StAR mRNA appeared later during follicular growth, in follicles >1 mm in diameter (type 6). LH-R and 17αOH mRNAs were found exclusively in the thecal cells, whereas StAR mRNA appeared in thecal cells, granulosa cells of late atretic follicles and oocytes. In early atresia, thecal cells expressed all three mRNAs, and their expression decreased gradually as atresia progressed. Atresia in granulosa cells was characterized by massive apoptosis of periantral, but not peribasal cells, that differentiated into luteal-like cells expressing StAR.In summary, our study suggests that in spite of the presence of 17αOH, a key enzyme in steroidogenesis, the ability to produce steroids by bovine follicles smaller than 1 mm in diameter must be very limited due to the absence of StAR protein. During the early stages of atresia, thecal cells remain morphologically and functionally healthy, and continue to express all three studied mRNAs.