Dissertations / Theses: 'Loss of a domesticated animal'

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Levine, Nadejda. "Wild Animals and Domesticated Landscapes: A Case Study of Human-Animal Relationships in the Middle and Late Woodland Coastal Plain of Virginia." W&M ScholarWorks, 2007. https://scholarworks.wm.edu/etd/1539626531.

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Tarkalson, David Dale. "PHOSPHORUS LOSS IN SURFACE RUNOFF FROM PIEDMONT SOILS RECEIVING ANIMAL MANURE AND FERTILIZER ADDITIONS." NCSU, 2001. http://www.lib.ncsu.edu/theses/available/etd-20010926-002603.

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The purpose of this research was to measure P losses in runoff from agricultural land in the Piedmont region of the southeastern U.S. with varying soil P levels and receiving broiler litter and inorganic P fertilizers. The experimental results will be helpful for the development of the P Loss Assessment Tool in North Carolina and other P Index approaches in states with similar soil characteristics and crop management practices. A net influx of P into many areas due to high animal populations has resulted in increased potential P losses to sensitive surface waters. A typical North Carolina broiler farm and dairy farm were found to have annual P surpluses of 65 kg P/ha and 20 kg P/ha respectively. The use of low phytic acid corn varieties and phytase enzyme has the potential to reduce the P surplus on broiler farms by 25 to 58%. Phosphorus losses in runoff from Piedmont conventional till (CT) and no-till (NT) soils with varying soil P concentrations and from soils currently receiving broiler litter and fertilizer P applications were assessed. In these studies, rainfall simulation at rates of 6 and 7.6 cm/hr were utilized to collect runoff samples from crop land with a range of initial P concentrations and from plots with varying fertilizer P and broiler litter application rates, both incorporated and broadcast. Runoff samples were collected at 5-min intervals for 30 min and analyzed for reactive P (RP), algal-available (AAP), and total P (TP). Concentration of RP in runoff from CT and NT plots was positively correlated with Mehlich-3 extractable P (r2 = 0.61 and 0.7 respectively) and oxalate extractable degree of P saturation (DPS) (r2 = 0.6 and 0.61 respectively). However, only TP mass loss (kg TP/ha) in runoff from CT was correlated with DPS (r2 = 0.57). A Mehlich 3 extractable P concentration of 350 mg P/kg and a DPS of 84% corresponded to 1 mg RP/L in runoff. Incorporation of broiler litter and inorganic P fertilizer into the soil at all P application rates virtually eliminated P runoff loses and had similar P losses in runoff as the unfertilized control. Surface application of broiler litter resulted in runoff containing between 2.9 and 24.5 mg RP/L for application rates of 8 to 82 kg P/ha respectively. Mass loss of TP in runoff from surface-applied broiler litter ranged from 1.3 to 8.5 kg P/ha over the same application rates. There was no significant relationship between surface applied inorganic P application rate and RP concentrations or TP mass losses in runoff. However, there was a trend for increased RP concentrations and TP mass losses in runoff with increasing application rate. Concentration of RP and mass loss of TP in runoff from surface applied inorganic P averaged 4.9 mg RP/L and 1.1 kg P/ha over all application rates. There was no significant difference between P losses in runoff from plots receiving surface applied conventional broiler litter and broiler litter derived from birds fed a low phytic acid corn (High Available P corn).

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McGill, Trevor, and University of Lethbridge Faculty of Arts and Science. "Cell therapy limits loss of vision in an animal model of retinal degenerative disease." Thesis, Lethbridge, AB : University of Lethbridge, Faculty of Arts and Science, 2004, 2004. http://hdl.handle.net/10133/274.

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The Royal College of Surgeons (RCS) rat was used as a model of human retinal degenerative disease, and for studying the efficacy of cell transplanation treatments. In order to characterize the spatial vision of the RCS strain, the visual acutiy and contrast sensitivity of adult non-dystrophic RCS rats was measured. The acuity and contrast sensitivity of these rats was normal. The acuity of dystrophic RCS rats was alos characterized to determine how photoreceptor degeneration affects vision. These rats progressively lost visual acuity from one month of age until elevn months of age when they were judged to be blind. The degeneration of vision in these animals was more protacted than would be predicted from previous anatomical and electrophysiological measures. Subretinal transplantation of human-derived Retinal Pigment Epithelial (RPE) cells and human Schwann cells into the dystrophic RCS rat significantly delayed the loss of visual acuity. These studies show that cell transplantation may be a viable method of limiting loss of vision in humans with retinal degenerative blinding diseases. vii, 77 leaves ; 29 cm.

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Coventry, T. L. "Loss of social status as an animal model of depression : an evaluation of validity." Thesis, Swansea University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.636304.

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McCullough, Brendan J. "The deafwaddler mouse as a model for human hearing loss /." Thesis, Connect to this title online; UW restricted, 2005. http://hdl.handle.net/1773/10627.

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Pyszczynski, Adam D. "Nondrug Reinforcement Loss and Relapse to Alcohol Seeking in Another Context." DigitalCommons@USU, 2011. https://digitalcommons.usu.edu/etd/865.

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Extinguished alcohol-maintained responding has been shown to relapse in aresurgence preparation when food-reinforced responding is subsequently extinguished within the same context. However, drug and nondrug reinforcers are often specific to different contexts. Accordingly, the present experiments sought to determine whether loss of an alternative source of nondrug reinforcement in one context could produce relapse to drug seeking in a separate context. In one experiment, rats made topographically different responses for food or alcohol in alternating components of a multiple schedule. Both reinforcers were delivered during baseline, alcohol was withheld during the second phase of the experiment, and finally both reinforcers were withheld during the final phase. Extinguished alcohol-maintained responding increased upon discontinuation of food deliveries, but may have increased due to similarity between the final experimental phase and an initial training phase. In a second experiment, the training phase that complicated interpretation of the elevated responding observed in Experiment 1 was eliminated altogether. Alcohol seeking again relapsed upon discontinuation of food, suggesting that the training conditions were not the cause of the observed relapse in Experiment 1. Thus, loss of a nondrug reinforcer in one context can produce relapse to drug seeking in another. This procedure may provide a novel model of drug relapse in which loss of context-specific, alternative nondrug reinforcers precipitates relapse to drug seeking in a separate context.

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Wolmarans, Wilhelm J. "The effect of transport on live weight loss, meat quality and blood haematology in slaughter ostriches." Thesis, Stellenbosch : University of Stellenbosch, 2011. http://hdl.handle.net/10019.1/6762.

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Thesis (MScAgric (Animal Sciences))--University of Stellenbosch, 2011. ENGLISH ABSTRACT: The production and export of ostrich meat from southern Africa, to especially the European Union, are increasing rapidly due to the healthy nature of ostrich meat. The European Union has very high standards when importing food products, and it is inevitable that more emphasis is being placed on the production of high quality ostrich meat. Another aspect also of concern to consumers, is the welfare of animals prior to slaughter, and this forces producers to look at ways to decrease stress of animals during the ante-mortem period. Research regarding the effect of stress during the ante-mortem period, and as a result, on meat quality, haematology and weight loss in ostriches, is lacking and thus the purpose of this study was to investigate the effect of various transport distances, travel conditions and different birds on these factors. Ante-mortem stress was measured using serum corticosterone levels (ng/ml), heterophil: lymphocyte (H:L) ratio, white blood cell (WBC) count, aspartate aminotransferase (AST) and creatine kinase (CK), as well as the rate and extent of pH decline in the M. gastrocnemius. Special emphasis was also placed on the meat quality parameters drip loss, cooking loss, colour and Warner-Bratzler shear force (kg/1.27 cm diameter). Live weight losses, as well as carcass weight and weight of bruises cut off from each bird were also recorded during various stages of the trials. The effect of transport distance on the meat quality of ostriches was investigated. Ultimate pHu measurements were taken at 24 hours post-mortem. The muscles of the ostriches from the control group (i.e. birds that were not transported prior to slaughter) had a lower mean pHu (5.77 ± 0.053) than birds that travelled 60 (5.93 ± 0.053) and 600 km (6.11 ± 0.053), respectively. Differences in meat drip loss percentage were also observed between the three treatments. The birds in the control group (0.40 ± 0.07 %) had the lowest meat drip loss percentage compared to the birds that travelled 60 km (treatment C) (1.36 ± 0.07 %) and 600 km (treatment B) (0.97 ± 0.07 %), respectively, to a commcerical ostrich abattoir. Ostriches that were transported for 600 km (8.13 ± 1.16 %) had a greater percentage live weight loss during the antemortem period than birds that travelled a distance of 60 km (2.4 ± 2.185 %) to the abattoir, although both groups were deprived of feed for the same period. When the haematology of the groups that travelled different distances was compared at various time intervals in the ante-mortem period, both groups of birds experienced significant increases in WBC, s-AST and s-CK. An increased H:L ratio from pre-transport to post-transport was only evident in the birds that travelled 600 km (treatment B). However, the birds that travelled 60 km were the only group of birds that had significant elevated serum corticosterone levels during the ante-mortem period. The increase in the various blood parameters indicates severe physical stress, which negatively affected meat quality. Another trial also investigated the effect of various farming systems and transport on meat quality and bruising of ostrich carcasses. Ostriches were raised in three different farming systems, i.e. feedlot -, semiintensive - and free range conditions. Other factors that could maybe impact on stress susceptibility, such as road conditions, floorspace and floor type were also investigated. A significant difference in meat pHu was found between ostriches that were raised in a feedlot (5.95 ± 0.018) and semi-intensive (6.04 ± 0.033) environment. The feedlot birds also had the greatest percentage of carcass weight removed due to bruising. The free range birds were the birds that had the lowest floor density per birds and also had the least amount of bruising on their carcasses. Incidently the other two groups (feedlot and semi intensive) were the birds that travelled on the same type of road (mountain pass) in a truck with rubber flooring whilst the free range birds travelled on a straight road in trucks with metal grid floors.The results indicate that the type of farming system didn’t have a significant influence on meat quality of ostriches, but that factors such as road conditions, flooring and bird density did play a significant role in the incidence of bruises and injuries obtained during transport. AFRIKAANSE OPSOMMING: Die produksie en uitvoer van volstruisvleis vanuit suidelike Afrika, na veral die Europese Unie, is gedurig aan die toeneem as gevolg van die gesonde aard van volstruisvleis. Die Europese Unie het baie hoë standaarde wanneer dit kom by die invoer van voedselprodukte en dit is onvermydelik dat meer klem op die produksie van hoë gehalte volstruisvleis gelê word. ŉ Ander aspek wat ook kommer wek by verbruikers is die welstand van diere voor slagting en hierdie aspek noodsaak produsente om te kyk na maniere om stres te beperk tydens die periode voor slagting. Navorsing rakende die effek van stres tydens die ante-mortem periode, asook vleiskwaliteit, hematologie en gewigsverlies in volstruise as gevolg van vervoer, ontbreek. Die doel van die studie was dus om die invloed van verskillende vervoerafstande, vervoersomstandighede en tipe produksiesisteme op volstruise se stresrespons te ondersoek. Die omvang van ante-mortem stres is bepaal deur die serum-kortikosteroon vlakke (ng/ml), heterofiel: limfosiet (H:L) ratio, witbloedsel (WBS) telling, aspartaat aminotransferase AST en creatien kinase CK, asook die tempo en vlak van pH-daling in die M. gastrocnemius, te meet. Spesiale klem is gelê op die vleisgehalte parameters kookverlies, drupverlies, kleur en Warner-Bratzler-skeurwaardes (kg/1.27 cm deursnee). Gewigsverlies is aangeteken op verskillende stadiums tydens die proewe. Karkasgewigte en die hoeveelheid gewig afgesny van elke volstruiskarkas a.g.v. kneusings is ook bepaal. Die eerste studie het die invloed van vervoerafstand op vleiskwaliteit van slagvolstruise ondersoek. Vleis kwaliteit parameters soos pH, drip verlies, kook verlies, taaiheid en kleur is ondersoek. Die pHu metings is op 24 uur post-mortem geneem. Slagvolstruise in die kontrole groep (d.i. -volstruise wat nie voor slagting vervoer is nie) het ’n laer vleis pHu (5.77 ± 0.05) gehad as voëls wat onderskeidelik 60 km (5.93 ± 0.05) en 600 km (6.11 ± 0.05) ver vervoer is. Verskille in persentasie dripverlies is gesien tussen die vleis van die voëls wat nie vervoer is nie (0.40 ± 0.07 %) en die voëls wat 60 km (1.36 ± 0.07 %) en 600 km ver (0.97 ± 0.07 %) onderskeidelik vervoer is. Volstruise wat vir 600 km (8.13 ± 1.16 %) vervoer is, het ‘n groter persentasie lewende gewig tydens die ante-mortem periode as voëls wat 60 km (2.4 ± 2.19 %) ver vervoer is na die abattoir, verloor, al was beide groepe weerhou van voer vir dieselfde tydperk. Beide groepe wat vervoer is (60 en 600 km) het merkbare toenames in witbloedsel (WBS) tellings, s-AST’s en s-CK’s getoon tydens die ante-mortem periode. Daar is slegs ŉ toename in H:L ratio (ŉ indikator van stres) van voor vervoer tot na vervoer gesien in die voëls wat 600 km vervoer is. Daarteenoor was die voëls wat slegs 60 km vervoer is die enigste voëls wat ŉ toename in korticosteroon vlakke getoon het gedurende die ante-mortem periode. Die toenames is heel moontlik ‘n aanduiding van erge fisiese stres wat ‘n negatiewe effek op vleiskwaliteit het. Die tweede studie het die effek van verskillende produksiesisteme en die stress respons van die verskillende groepe slagvolstuise op vervoer ondersoek. Vleis kwaliteit parameters soos pH, drip verlies, kook verlies en taaiheid is ondersoek. Die hoeveelheid kneusings per volstruis is ook gemeet. Daar was ‘n beduidende verskil (P = 0.009) tussen die pHu van die voerkraal (5.95 ± 0.018) en semi- intensiewe (6.04 ± 0.033) volstruise. Die voerkraal volstruise se vleis het die grootste drip- en kookverliese gehad in vergelyking met die ander twee groepe (semi-intensiewe en ekstensiewe) terwyl die ekstensiewe volstruise die taaiste vleis gehad het. Die voerkraalvoëls het ook die grootste persentasie karkasgewig verloor a.g.v. kneusings wat afgesny is. Die ekstensiewe voëls het die laagste vloer digtheid per volstruis gehad asook die minste kneusings. Die ander twee groepe (voerkraal en semi intensief) was die groepe wat op dieselfde pad vervoer is (bergpas) in vragmotors wat rubber vloere gehad het terwyl die ekstensiewe voêls op ‘n reguit pad vervoer is in ‘n vragmotor met ‘n metaal oppervlakte. Die resultate van die studie is ‘n aanduiding dat die tipe plaassisteem nie ‘n groot impak op die hoeveelheid akute stres ervaar deur die voëls tydens vervoer gehad het of gevolglik op die vleiskwaliteit van die volstruise nie, maar dat faktore soos pad toestand, tipe vloer en voëldigtheid wel ‘n wesenlike rol speel in die voorkoms van kneusings en beserings opgedoen tydens vervoer.

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Santos, Endrigo Sperto Rodrigues dos. "Correlação entre doença aterosclerótica, dieta hipercolesterolêmica e as perdas dentais, estudo em modelo animal." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/23/23147/tde-28042009-095027/.

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O objetivo deste trabalho foi de avaliar em Modelo animal, coelhos (raça Nova Zelândia) divididos em três grupos randomizados, (jovem com 60 dias (G1), um idoso com aterosclerose e ingestão de colesterol (G2) e um idoso com aterosclerose e sem ingestão do colesterol (G3)) se, a dieta rica em colesterol e a idade, causam lesões de aterosclerose e placas ateroscleróticas nos animais, alterações nos comprimentos dos dentes, aumento ou diminuição dos espaços periapicais dos dentes, perda óssea alveolar na maxila e mandíbula. Através da metodologia descrita e após as análises histológicas e morfológicas, verificou-se diferença estatisticamente significante, nas variáveis dos comprimentos dos dentes 1º prémolares superiores entre os grupos G3 versus G1 p<5%. médias de 1247,88 (p=0,017) e G3 versus G2, com diferença das médias de 1190,85 (p=0,025) ou seja o comprimento dos dentes fora diferente no grupo G2. Com relação à variável, espessura do osso alveolar, não ocorreu significância estatística, porém tendências de que este esteja sendo alterado. Com relação a variável espessura do espaço periapical fora verificado significância estatística com p=0,017 em relação ao G1, na região dos 1º Pré-molares, apresentando a diferença das médias (403,42) a favor do G2, ou seja aumento do espaço periapical. A variável da área de placa de aterosclerose, correlacionada, com os comprimentos dos dentes e espessura do osso alveolar, também teve resultado significante na região 1º e 2º pré-molares entre G2 e G3. com p=0,025 e r=0,476. Confirmando assim a correlação da aterosclerose, dietas hiperclesterolêmicas e as alterações da cavidade bucal e estrutura de sustentação dos dentes. The aim of this study is, to evaluate on animal model (New Zealand rabbits), on different and randomized groups (G1 a young group, G2 an older rabbit, with atherosclerosis and ingesting hipercholesterolemic fat diet and another group G3, just an older group) investigated than the hipercholesterolemic fat diet induced atherosclerotic lesions and plaques in ascendant aorta, bone loss in maxillary and jaw, alterations on length of the tooth, alterations on tooth periapical spaces. By the methodology described and aplicated, before the histological and morphological analysis, was verified significant statistical variance in the length of the first premolar tooth and second premolar on maxillary region, the length of this tooth is reduced in G2 (p<5%). The medias are 1247,88 (p=0,017) and 1190,85 (p=0,025). Analyzing another variable on the alveolar bone thickness, was not found any statistical significance, but tendencies that this event may occur. According to another variable of the thickness found on the periapical space, it was verified a significant variable statistic such as p=0,017 related on G1, on first premolar region, suggesting a different statistic, between medias, favoring G2 meaning the increase of periapical space. The variable on the atherosclerosis plaque area, related to the teeth length and alveolar bone thickness, also showed significant results on first and second premolars regions between G2 and G3, with p=0,025 and r=0,476. That confirms the atherosclerosis correlations and hipercholestrolemic fat diet, also alterations in oral cavity and teeth implantation structure.

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Darr, Matthew J. "Advanced embedded systems and sensor networks for animal environment monitoring." Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1196199349.

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Coates, Ashley Nicole. "Wildlife Town Center: Reimagining Landmark Mall as a Space for Reconnecting with the Urban Flora and Fauna." Thesis, Virginia Tech, 2021. http://hdl.handle.net/10919/104157.

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Urban development typically displaces or extirpates wildlife and decreases habitat. While some species such as the grey squirrel and raccoon adapt well to urban living, other species are less successful due to a lack of habitat or the loss of other species. As urbanization continues, the way that humans develop land and interact with species living on that land must be reevaluated. One development model that has been common in the Washington DC area is multi-use development. This development type accommodates various land uses in a small area. The layout of multi-use developments typically includes a central open area for events surrounded by retail and restaurants on the ground level and apartments and office space above. This creates a community where people have all of their needs for goods, housing, and work met within a small area. Another name for these types of multi-use developments is a Town Center. One of the newest proposed multi-use developments in the Washington DC area is at the former Landmark Mall location. The development aims to revitalize the now closed Landmark Mall in Alexandria, Virginia. As a design in development, the Landmark Mall Redevelopment Plan is a prime opportunity to explore a new concept for development: a wildlife town center. In my experience, typical Town Centers are not designed for wildlife. They are designed for heavy human foot traffic with plant selections and surfaces to withstand such traffic. How might a town center be re-imagined to support wildlife and also provide for humans? Animal Aided Design is one strategy. The process of Animal Aided Design takes a sampling of species that could live in a landscape and provides the critical needs for those species. This thesis takes the process of Animal Aided Design and applies it to the Landmark Mall Redevelopment Plan. While the design focuses on five particular bird species, the intention is to create conditions that will suit many more than those five species and that the site will attract a variety of birds as year-round residents, as well as those passing through during migration or staying for the breeding season. The project creates a novel habitat to help increase the viable living and foraging areas for wildlife and protects wildlife populations, while giving people the opportunity to find joy in their interactions with other species. Master of Landscape Architecture Urban development decreases available habitat and causes wildlife to move to new areas or perish. While some species such as the grey squirrel and raccoon adapt well to urban living, other species are less successful due to a lack of habitat or the loss of other species. As development in urban areas continues, the way that humans develop land and interact with species living on that land must be reevaluated. One development model that has been common in the Washington DC area is multi-use development. This development type accommodates various types of businesses and housing to exist near each other in a small area. The layout of multi-use developments typically includes a central open area for events surrounded by retail and restaurants on the ground level and apartments and office space above. This creates a community where people have all of their needs for goods, housing, and work met within a small area. Another name for these types of multi-use developments is a town center. One of the newest proposed town center developments in the Washington DC area is at the former Landmark Mall location. The development aims to revitalize the now closed Landmark Mall in Alexandria, Virginia into a place for community gathering. As a project in development, the Landmark Mall Redevelopment Plan is a prime opportunity to explore a new concept for development: a wildlife town center. In my experience, typical Town Centers are not designed for wildlife. They are designed to withstand people walking around with their children and pets. The plant selection in these areas are not typically native and have little benefit to the local wildlife. How might a town center be re-imagined to support wildlife and also provide for humans? One would take an approach that is more holistic and designs for the basic needs of wildlife as well as the humans. This strategy is called Animal Aided Design. This thesis takes the process of Animal Aided Design and applies it to the Landmark Mall Redevelopment Plan. While the design focuses on five particular bird species, the intention is to create conditions that will suit many more than those five species and that the site will attract a variety of birds as year-round residents, as well as those passing through during migration or staying for the breeding season. The project creates a novel habitat to help increase the viable living and foraging areas for wildlife and protects wildlife populations, while giving people the opportunity to find joy in their interactions with other species.

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Gregorich, Jenna L. "Effects of Induced Moisture Loss on Broiler Chicks Immune Response Post Salmonella enteritidis Lipopolysaccharide Challenge." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu149985847613047.

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Bair, Necia Beck. "A Hydrothermal After-ripening Time Model of Seed Dormancy Loss in Bromus tectorum." BYU ScholarsArchive, 2004. https://scholarsarchive.byu.edu/etd/533.

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After-ripening, the process of seed dormancy loss in dry storage is associated with a decrease in the mean base water potential, one of the parameters of hydrothermal time. The rate of change of the mean base water potential is assumed to be a linear function of temperature above a specific base temperature and as a result can be described by a thermal after-ripening (TAR) time model, an extension of hydrothermal modelling. The thermal requirement for after-ripening is the thermal time necessary for the modelling base water potential of the seed to shift from its original value to its final value. In order to include the effects of water potential on the rate of dormancy loss, a hydrothermal after-ripening (HTAR) time model was developed. Laboratory and field studies were conducted using seeds of Bromus tectorum. These studies identified four important ranges of water potential that influence the rate of dormancy loss. The ranges are identified as follows: seeds experiencing soil water potentials seeds experiencing soil water potentials <-400 MPa do not after-ripen, between -400 MPa and -150 MPa seeds after-ripen as a function of temperature (T) and water potential (Ψ), seeds experiencing water potentials >-150 MPa after-ripen as a linear function of temperature, and somewhere above -40 MPa seeds are too wet to after-ripen. These ranges suggest that specific reaction thresholds associated with non-fully imbibed seeds also apply to the process of after-ripening. The HTAR model for B. tectorum seeds generally improved predictions of dormancy loss in the field under soil conditions that were too dry for TAR alone. Reduced after-ripening rate under extremely dry conditions is ecologically relevant in explaining how seeds may prolong dormancy under high soil temperature conditions.

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Marx, Fábio Ritter. "Biodisponibilidade da gordura em dietas para carnívoros : efeitos dietéticos e da espécie animal." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2016. http://hdl.handle.net/10183/143158.

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As gorduras são componentes importantes em dietas para carnívoros, porém o aproveitamento pelos animais sofre influência de fatores inerentes à composição das dietas, principalmente fibras e minerais, que precisam ser melhor estudados. Os trabalhos que avaliam as perdas endógenas de gordura nas fezes (PEGF) e os efeitos na digestibilidade aparente da gordura são escassos e divergentes. Desta forma, os objetivos destes estudos foram: determinar as PEGF em cães e mink; utilizar as PEGF para obtenção dos valores de digestibilidade verdadeira da gordura; além de avaliar os efeitos da composição de fibras dietéticas e a inclusão de emulsificantes no aproveitamento da gordura por cães. No primeiro estudo, as PEGF foram mensuradas em cães adultos. Dietas com níveis crescentes de gordura de frango foram utilizadas e as PEGF dos cães foram determinadas a partir de análises de regressão. As PEGF foram expressas em relação ao peso corporal (PC) dos animais, 155 mg/kg PV/dia, ou em relação ao consumo de gordura na matéria seca (MS), 7,9 g/kg MS consumida. A digestibilidade aparente total da gordura apresentou aumento conforme o consumo. A digestibilidade verdadeira total da gordura, corrigida para PEGF, não variou mediante o consumo de gordura. A relação entre PEGF e consumo de gordura foi maior em dietas com baixa gordura e explica o aumento na digestibilidade aparente da gordura quando concentrações maiores são consumidas. No segundo estudo, as PEGF foram determinadas em mink. Dietas com níveis crescente de óleo de soja foram formuladas e as PEGF avaliadas por regressão. Foi obtido o valor de 0,5 g/100g MS consumida, próximo ao relatado em cães. No terceiro estudo foi avaliada a influência das fibras dietéticas e da lecitina de soja na digestibilidade aparente da gordura em dietas para cães adultos. Foram avaliadas três fontes de carboidratos, amido de milho, celulose e polpa de beterraba, combinadas ou não à lecitina de soja. A polpa de beterraba reduziu a digestibilidade aparente e verdadeira da gordura em cães, aumentou o teor de umidade e elevou o escore fecal, porém ainda dentro da faixa considerada ideal. A lecitina de soja não apresentou efeito de melhora na digestibilidade dos macronutrientes e da energia das dietas. Fats are important components of carnivores diets, however inherent factors of diets composition, mainly fibers and minerals, may affect its use by the animals, requiring further studies. Studies evaluating endogenous fat loss (EFL) and the effects on apparent total tract digestibility of fat are limited and divergent. The objectives of these studies were: to determine the EFL in dogs and mink; apply the EFL to calculated the true total tract digestibility of fats; and to evaluate the effects of dietary fiber composition and an emulsifying agent on fats digestibility in dogs. On the first study, the EFL was evaluated in adult dogs. Diets with increasing levels of poultry fat were used and the EFL was determined by regression analysis. The EFL was obtained according to the dogs’ body weight (BW) as 155 mg/kg BW/day, or according to dry matter (DM) fat intake, as 7.9 g/kg DM intake. The apparent total tract digestibility of fat increases according to the intake level. However, the true total tract digestibility of fat, EFL corrected, remained unaffected by fat intake. The relation between EFL and fat intake is higher for low fat diets and explains why the apparent digestibility increases according to intake. On the second study, the EFL was measured in mink. Diets with graded levels of soybean oil were offered and the EFL evaluated by regression. The value of 0.5 g/100 g DM intake was obtained, close to the reported with dogs. The third study assessed the influences of dietary fibers and soy lecithin on apparent total tract digestibility of fat in adult dog diets. Were evaluated three carbohydrate sources; corn starch, cellulose and beet pulp; combined or not with soy lecithin. The beet pulp decreased apparent and true total tract digestibility of fat in dogs, increased the moisture level of faeces and the faecal score, yet the faeces still had good quality. The soy lecithin did not improve digestibility of macronutrients and energy of diets.

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Fischer, Manuela Marques. "Influência da obesidade, restrição energética e castração na microbiota intestinal de cães e gatos." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2015. http://hdl.handle.net/10183/132500.

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Os métodos de tratamento para a obesidade em cães e gatos focam na restrição calórica, seja restringindo a ingestão de alimento ou alimentando o animal com dietas hipocalóricas. Entretanto, esses métodos frequentemente falham, sendo necessárias estratégias alternativas para promover a perda de peso. O objetivo desse estudo foi investigar as diferenças na microbiota fecal entre animais magros e obesos e determinar se a castração e/ou a perda de peso estão associadas com mudanças na população microbiana. No primeiro experimento, a composição da microbiota fecal foi avaliada nos gatos magros inteiros, magros castrados e obesos castrados, antes e depois da perda de peso. Os gatos obesos foram submetidos a seis semanas de restrição energética e apresentaram redução na massa gorda após a perda de peso (P<0,001), embora o peso corporal não tenha mudado (P>0,05). Firmicutes, seguido de Bacteroidetes foram os filos predominantes em todos os grupos. O grupo dos magros castrados tiveram o perfil de bactérias que era esperado para os obesos, com maior abundância de Firmicutes e menor de Bacteroidetes (P<0,05). Não foram observadas diferenças entre os grupos magros inteiros e obesos castrados. A população microbiana dos gatos obesos mostrou poucas alterações com a perda de peso. No segundo experimento, o teste foi realizado quando os cães estavam magros, após consumo ad libitum para promover o ganho de peso e após a perda de peso. As seguintes concentrações séricas foram analisadas: glicose, colesterol, triglicerídeos, albumina, creatinina, fosfatase alcalina (FA), alanina aminotransferase (ALT), proteínas totais (PT), insulina e leptina. As amostras de fezes foram analisadas para determinar a abundância de Bacteroidetes e Firmicutes. As concentrações de triglicerídeos, colesterol, albumina, FA, ALT e PT foram maiores (P<0,05) nos cães obesos quando comparados aos magros. Bacteroidetes foi mais abundante (P<0,001) nos magros e Firmicutes não diferiu entre os grupos (P>0,05). Após a perda de peso, os níveis de colesterol e PT e a abundância de Bacteroidetes permaneceram inalteradas estatisticamente. Conclui-se então que, nos modelos testados, há diferenças na microbiota fecal entre os grupos dos estudos realizados. Entretanto, no estudo com os gatos a obesidade pareceu não influenciar o crescimento das diferentes populações de microorganismos. Treatment methods for obesity in dogs and cats focus on calorie restriction, either by restricting the calorie intake of the animal, or by feeding energy diluted diets. However, these methods often fail, requiring additional strategies to promote weight loss. The objective of this study was to investigate differences in the gut microbiota between lean and obese animals and determine whether neutering and/or weight loss are associated with changes in the microbial populations. In the first experiment, the composition of the faecal microbiota was evaluated in lean intact, lean neutered and obese neutered cats, before and after weight loss. The obese cats were submitted to six weeks of energy restriction and showed less fat body mass after weight loss (p<0.001), although the body weight has not changed (P>0.05). Firmicutes followed by Bacteroidetes were the predominant bacterial phyla in all groups. The lean neutered cats had a bacterial profile of what one would expect from the obese cats, with greater abundance (P<0.05) of Firmicutes and lower abundance (P<0.05) of Bacteroidetes. There were no significant differences between lean intact and obese neutered. The microbe populations of obese cats showed very few changes with weight loss. In the second experiment, testing was performed when the dogs were lean, after ad libitum feeding to promote weight gain and after weight loss. Serum concentrations were analyzed: glucose, cholesterol, triglycerides, albumin, creatinine, alkaline phosphatase (ALP), alanine aminotransferase (ALT), total proteins (TP), insulin and leptin. Faecal samples were analyzed to determine the abundances of Bacteroidetes and Firmicutes. Triglycerides, cholesterol, albumin, PA, ALT and TP were greater (P<0.05) in obese dogs when compared to the lean. The abundance of Bacteroidetes was greater (P<0.001) in the lean group and the phylum Firmicutes showed no differences among the groups (P>0.05). After weight loss, the levels of cholesterol and TP and the abundance of Bacteroidetes remained unchanged statistically. In conclusion, differences in the faecal microbiota were observed among the groups of both studies. However, in the study with cats, obesity seems not to influence the growth of diverse populations of microrganisms.

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Oliveira, Déria de. "O luto pela morte do animal de estimação e o reconhecimento da perda." Pontifícia Universidade Católica de São Paulo, 2013. https://tede2.pucsp.br/handle/handle/15313.

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Made available in DSpace on 2016-04-28T20:38:47Z (GMT). No. of bitstreams: 1 Deria de Oliveira.pdf: 4690787 bytes, checksum: 8f696230d02df0b79aecaf054817516f (MD5) Previous issue date: 2013-11-14 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior The domestic animal is considered a family member and it fills individual needs, improving the pet‟s owners‟ self-esteem by offering affection and companionship, among other perceived benefits. On the other hand, when a pet dies, an emptiness overcomes the owner, with grief by the loss of a significant creature in his life history. The aim of this study was to investigate, by means of a quantitative research, the recognition of the loss by pet‟s death. For this purpose, a survey was done by means a questionnaire published and answered on a page available on the internet by bereaved pet owners whose pet had died less than five years before. The study had 360 participants. A qualitative research was also done with a recorded interview, looking to describe the grief of six bereaved owners who lost their pets by pet´s death less than one year from the date of the interview to comprehend the bond formed with the animals. The grief is similar to the one which takes place when a dear person dies. This outcome suggests that there are three categories of dyads between people and pets: 1) relational dyad, 2) bond dyad and 3) attachment dyad that influencing in the differences of the intensity in their distress and lasting grief. Other studies to assess primary attachment styles and adulthood are necessary to confirm and to deepen these results, considering the repercussion in the bond with pets O animal doméstico é hoje considerado um membro da família e preenche necessidades individuais, melhorando a autoestima dos proprietários, por fornecer afeto e companhia, entre outros benefícios percebidos. Por outro lado, quando um animal de estimação morre, abre-se uma lacuna na vida de seu proprietário, com luto pela perda de um ser significativo da sua história de vida. O objetivo deste estudo foi investigar por meio de uma pesquisa quantitativa, o reconhecimento da perda pela morte do animal de estimação. Para esta finalidade, foi realizada uma pesquisa utilizando-se um questionário divulgado e preenchido em uma página disponibilizada na Internet, por enlutados há menos de cinco anos. O estudo contou com 360 participantes. Foi efetuada também uma pesquisa qualitativa, com realização de entrevista gravada, buscando descrever o luto de seis pessoas pela morte de seus animais há menos de um ano da data da entrevista e compreender o vínculo formado com os animais. Verificou-se que o luto é semelhante ao que ocorre quando morre uma pessoa querida. Os resultados sugerem que podem ser formadas três categorias de díades entre pessoas e animais de estimação: 1) díade relacional; 2) díade vinculada e 3) díade de apego, que influenciarão na intensidade do sofrimento e no luto mais prolongado. Outros estudos, para avaliar os estilos de apego primários e na vida adulta são necessários, para confirmar e aprofundar estes resultados, considerando a repercussão no vínculo com os animais de estimação

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Graß, Ingo [Verfasser], and Nina [Akademischer Betreuer] Farwig. "Habitat loss and exotic plant invasions disrupt plant-animal mutualisms in a heterogeneous South African landscape / Ingo Graß. Betreuer: Nina Farwig." Marburg : Philipps-Universität Marburg, 2014. http://d-nb.info/105193494X/34.

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Reilly, Melissa. "The Lived Experience of Grief After the Death of a Long-Term Companion Animal." Antioch University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=antioch1527018092359502.

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Bertoli, Claudia Damo. "Modelos e metodologias para estimação dos efeitos genéticos fixos em uma população multirracial Angus x Nelore." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2015. http://hdl.handle.net/10183/128116.

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Os objetivos deste trabalho foram estimar os efeitos genéticos fixos atuando sobre uma população sintética e testar diferentes modelos e metodologias neste processo de estimação. Os efeitos genéticos fixos testados foram os efeitos aditivos direto e materno de raça e não aditivos diretos e maternos de heterose, perdas epistáticas e complementariedade. Os modelos testados incluem alternada e conjuntamente todos estes efeitos. As metodologias de regressão de cumeeira e regressão por quadrados mínimos foram comparadas assim como dois métodos distintos para determinação do ridge parameter. Uma população sintética, envolvendo as raças Angus e Nelore foi utilizada. Foram utilizados 294.045 registros de desmame e 148.443 registros de sobreano de uma população sintética envolvendo as raças Angus e Nelore. Foram estudadas as seguintes características: ganho de peso do nascimento ao desmame (WG), escores de conformação (WC), precocidade (WP) e musculatura (WM) coletados ao desmame, ganho de peso do desmame ao sobreano (PG), escores fenotípicos de conformação (PC), precocidade (PP) e musculatura (PM) e perímetro escrotal (SC) coletados ao sobreano. Na maioria das análises, os efeitos genéticos fixos estimados foram estatisticamente significativos. O modelo completo, incluindo todos os efeitos genéticos fixos foi o mais indicado nas duas metodologias testadas. Na estimação por regressão de quadrados mínimos, o modelo mais parcimonioso foi o que incluiu apenas os efeitos aditivos de raça e não aditivos de heterose (dominância) e na estimação por regressão de cumeeira o mais parcimonioso foi o aquele que incluiu, além dos dois já referidos, os efeitos não aditivos de perdas epistáticas. As metodologias mostraram-se equivalentes, para os modelos que incluíram apenas efeito aditivo de raça e não aditivo de heterose. Todavia com a inclusão dos efeitos não aditivos de perdas epistáticas e/ou complementariedade, a regressão de cumeeira mostrou-se mais indicada até o momento em que os dados atingiram um determinado volume e estrutura, com grande parte das classes de composições raciais representadas na amostra e, a partir daí os modelos se mostraram equivalentes. Na comparação entre os métodos de determinação do ridge parameter, o mais indicado foi o método que identifica o menor valor possível que produz fatores de inflação de variância abaixo de 10 para todos os regressores estimados. The objectives of this study were to estimate the fixed genetic effects acting on a synthetic population, as well as test different models and methodologies in this estimation process. The tested fixed genetic effects were the direct and maternal breed additive and direct and maternal heterosis, epistatic loss and complementarity non-additive effects The tested models include alternate and together all these effects. The ridge regression and least square regression methodologies were compared and were also compared two different methods for determining the ridge parameter to use in the ridge regression. A synthetic beef cattle population, involving Angus and Nellore in several breed combinations was used. 294,045 records at weaning and 148,443 records at yearling were used. The traits of weight gain from birth to weaning (WG), phenotypic scores of conformation (WC), precocity (WP) and muscling (WM) collected at weaning, weight gain from weaning to yearling (PG), phenotypic scores of conformation (PC), precocity (PP) and muscles (PM) collected at yearling and scrotal circumference (SC) were used in the analyzes. In most of analyzes, the estimated fixed genetic effects were statistically significant. The complete model, including all fixed genetic effects was the most suitable in the two tested methodologies. In the estimation by least squares regression, the most parsimonious model was the model that included only breed additive and non-additive heterosis (dominance) effects and in the estimation by ridge regression the most parsimonious model was that included, besides the breed additive and non-additive heterosis (dominance) effects, the non-additive epistatic loss effects. Comparing the two methodologies, for models that include only breed additive and non-additive heterosis effects, methodologies proved to be equivalent; with the inclusion of non-additive epistatic loss and / or complementarity effects, ridge regression was more indicated originally. After reached a certain volume and structure, with much of classes of breeds represented in the sample. Both least squares and ridge regression were equivalent. Comparing the methods for determining the ridge parameter, the best method was that which identifies the smallest possible value that produces the variance inflation factors below 10 for all estimated regressors.

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Sanchez, Paula Katherine Vargas. "CARACTERIZAÇÃO DO MODELO DE PERDA ÓSSEA ALVEOLAR INDUZIDA POR LIGADURA EM RATOS." UNIVERSIDADE ESTADUAL DE PONTA GROSSA, 2015. http://tede2.uepg.br/jspui/handle/prefix/1709.

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Made available in DSpace on 2017-07-24T19:22:01Z (GMT). No. of bitstreams: 1 Paula Katherine Vargas.pdf: 5773266 bytes, checksum: a57cf65240bf44b7027306a6aa4921a9 (MD5) Previous issue date: 2015-11-24 Peridontal research involves the use of animal models to facilitate the understanding of biological processes of periodontal disease (PD), and the potential of new and existing therapies, therefore the induction of periodontal disease is needed. In the literature, the most widely used model for the induction of periodontal disease in rats is ligature. It is an insertion of a cotton yarn around the cervix of the first mandibular molar resulting in the accumulation of a bacterial biofilm, and triggering a local inflammatory response and the consequent alveolar bone loss (ABL). The methods most commonly used to evaluate the ABL are radiographic, histologic and morphometric. Which measure the distance between the cemento-enamel junction and bone crest. Although these methods are widely used, it is unknown the possibility of extrapolating resuts between research groups and the intra-examiner (repeatability) and inter-examiner (reproducibility) agreement. Other parameters usually assessed are leukocyte migration (MPO) and the presence of nitric oxide (NO), which are inflammatory markers. The aim of this study was characterized the kinetics of the ABL, leukocyte migration and nitric oxide at 0, 3, 7, 15, 30 and 60 days after induction of PD by ligature and evaluate the Bland-Altman concordance for the main assessment methodologies of ABL (radiographic, histologic and morphometric). 60 male Wistar rats between 250 and 300 g were randomly divided into 6 experimental groups (n = 10 animals /group) as follows: G0 (not treatment), G3 (ligature for 3 days) G7 (ligature for seven days) , G15 (ligature for 15 days), G30 (ligature for 30 days) and G60 (ligature for 60 days). After 0, 3, 7, 15, 30 and 60 days, animals were sacrificed by anesthetic overdose, and hemimandibles were removed for radiographic analysis, morphometric (linear and area) and histological. Also was collected adjacent gum tissue from mandibular first molar for leukocyte migration analysis and nitric oxide dosage. The results were analyzed with ANOVA followed by Tukey test and Bland Altman test to establish the correlation between the methodologies. In the radiographic analysis was observed a significant ABL after the third day, the intra-examiner and inter-examiner analysis showed a significant difference between the measurements. In linear morphometric analysis, the ABL was significant after the third day, in contrast to measure the area was significant only after the seventh day. The concordance analysis intra and inter-examiner did not show difference between these measurements. In histological measurement, the ABL was significant after the seventh day. The intra and inter-examiner analysis showed no difference between the measurements. The leukocyte migration had significant difference on the seventh day and the nitric oxide showed a peak of activity in the fifteenth day. It is concluded that radiographic analysis and morphometric-linear had a significant ABL on the third day, in contrast to morphometric-area and histological showed a significant ABL after the seventh day of induction. The peak of MPO activity occurs seven days after the induction of disease, for NO the peak occurs on the fifteenth day. In addition it was observed an agreement of Bland Altman intra and inter-examiner for the morphometric and histological methods. But the radiographic method did not show intra- and inter-examiner concordance. A pesquisa na área da periodontia envolve o uso de modelos animais para facilitar o entendimento de processos biológicos envolvidos na doença periodontal (DP) e o potencial das terapias novas e já existentes. Na literatura, o modelo mais utilizado para a indução da DP em ratos é a ligadura. Nesta metodologia há a inserção de um fio de algodão na região cervical de molares (inferiores e/ou superiores), promovendo assim um acúmulo de um biofilme bacteriano, o qual desencadeia uma resposta inflamatória local e a consequente perda óssea alveolar (POA). As metodologias mais utilizadas para avaliar a POA são: radiográfica, morfométrica e histológica. Embora estas metodologias sejam amplamente utilizadas, não há na literatura a avaliação de sua confiabilidade por meio de testes estatísticos de concordância, dificultando assim a extrapolação dos dados entre diferentes grupos de pesquisas ou até mesmo dentro um mesmo grupo. Em acréscimo, considerando que cada metodologia de avaliação da perda óssea analisa uma região específica (crista mesial e rebordo alveolar) e que o processo inflamatório é dinâmico, torna-se plausível que a perda óssea, bem como os marcadores da inflamação possuam uma cinética peculiar de evolução de acordo com o tempo de indução da DP. Neste sentido, este trabalho teve como objetivo avaliar a concordância de Bland-Altman para as principais metodologias de avaliação da POA (radiográfica, morfométrica e histológica) e caracterizar a cinética da POA,migração leucocitária e do óxido nítrico nos tempos 0, 3, 7, 15, 30 e 60 dias após a indução da DP por meio do método da ligadura. Para isso, 60 ratos Wistar machos entre 250g e 300g foram divididos randomizadamente em 6 grupos experimentais (n=10 animais/grupo), sendo: G0 (sem ligadura), G3 (ligadura por 3 dias), G7 (ligadura por 7 dias), G15 (ligadura por 15 dias), G30 (ligadura por 30 dias) e G60 (ligadura por 60 dias). Após os tempos experimentais, os animais foram sacrificados e as hemimandibulas removidas para determinação da POA por meio das metodologias: (1) radiográfica, (2) morfométrica (através das medidas linear e da área) e (3) histológica. Além disso foi coletado o tecido gengival adjacente à ligadura do primeiro molar inferior para as análises de migração leucocitária e quantificação de óxido nítrico. Concordância de Bland-Altman foi utilizada para a determinação da confiabilidade (intra e inter-examinador) para as diferentes metodologias de análise da POA. ANOVA seguido do teste de Tukey foi empregado para as avaliações de cinética da POA, da migração leucocitária e do óxido nítrico. O nível de significância foi de 5%. Na análise radiográfica foi observada POA estatisticamente significativa (em relação ao tempo 0) após o terceiro dia. A análise de concordância intra e inter-examinador mostrou diferença significativa entre as mensurações. Na análise morfométrica linear, a POA foi significativa após o terceiro dia, enquanto que na mensuração da área foi significativa apenas após o sétimo dia. A análise de concordância intra- e inter-examinador não mostrou diferença entre estas mensurações. Na mensuração histológica, a POA foi significativa após o sétimo dia. A análise intra e inter-examinador não mostrou diferença entre as mensurações. A migração leucocitária teve diferença significativa no sétimo dia, coincidindo neste, o seu pico de migração no tecido gengival. Para o óxido nítrico, embora o primeiro tempo de atividade com diferença significativa tenha sido com 7 dias, o seu pico de quantificação ocorreu no décimo quinto dia. Conclui-se que as análises radiográfica e morfométrica linear, apresentaram uma POA significativa em torno do terceiro dia, em contraste as análises morfométrica da área e histológica que mostraram uma POA significativa somente após o sétimo dia da indução da DP. O pico de migração leucocitária ocorre após sete dias da indução da doença, enquanto que para o pico de dosagem do óxido nítrico ocorre somente no décimo quinto dia. Em acréscimo foi observada uma concordância de Bland Altman intra e inter-examinador para as metodologias morfométricas e histológicas. Porém a metodologia radiográfica não apresentou concordância intra nem inter-examinador.

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Kettle, S. J. A. "The use of end-to-side repair of peripheral nerves for neurotization after loss of nerve tissue in a large animal model." Thesis, University of Edinburgh, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.653346.

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This study uses a large animal model to compare two variations of end-to-side neurorrhaphy techniques with conventional clinically established methods of nerve repair to assess the feasibility of end-to-side suture as a technique for possible future clinical use. All the experiments were randomized and the author performed all the surgery. The nerve repairs were assessed electrophysiologically and histologically and the muscles supplied by the repaired nerves were assessed physiologically. There were no significant differences in the outcomes of nerve repair between different conventional techniques. End-to-side nerve repair did support nerve regeneration but it was or nothing. When innervation of the distal nerve slump and the recipient FCR muscle did occur, the functional outcomes were inferior to conventional techniques of nerve repair apart from the twitch and tetanic tensions of the FCR muscle. Double end-to-side nerve repair consistently supported nerve regeneration but this repair was inferior to conventional techniques to nerve repair in all measures of outcome except twitch and tetanic muscle tensions. It is likely that regenerating axons used the epineurial and perineurial layers of the donor nerve segment between the two neurorrhaphy sites as a conduit for axon growth as well as regenerating axons from collateral sprouts in the end-to-side pathway. The function of the donor ulnar nerves in terms of conduction velocity was compromised in the double end-to-side repair but not the end-to-side repair. Assessment of the donor FCU muscles in terms of the muscle physiological experiments also needs to be properly tested. Further study is needed to assess the effects of placing the proximal neurorrhaphy site further away from the distal site in a double end-to-side neurorrhaphy, on nerve regeneration. It is not clear from this work why some of the end-to-side neurorrhaphies supported nerve regeneration and some did not, especially in the light of the fact than none of the repairs had dehisced macroscopically. Although end-to-side neurorrhaphy did support nerve regeneration with sometimes good return of muscle function, the use of this technique as a clinical tool at this time cannot be recommended.

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Sgrò, Alberto. "Tissue engineering for the surgical tratment of muscle defects: application on animal model of congenital diaphragmatic hernia and skeletal volume muscle loss." Doctoral thesis, Università degli studi di Padova, 2018. http://hdl.handle.net/11577/3426684.

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Background. Repair of skeletal muscle loss due to trauma, surgical resection or malformations represent a challenge for clinicians. Several attempts to create a bioscaffold to substitute skeletal muscle have been done but no satisfying results were obtained due to lack in regeneration process and functionality of repaired tissue. Some studies on tissue engineering investigated the application of decellularized extracellular matrix (ECM) derived from skeletal muscle observing positive effect towards regeneration. It is becoming relevant the role of tissue-specificity in the field of tissue engineering. This study aims to compare the regenerative effect of both tissue-specific and no tissue-specific scaffolds when applied in a volume of volume muscle loss. Muscle regeneration and macrophagic response are investigated. Material and Methods. Decellularized extracellular scaffold from murine skin, intestine and rhabdomyosarcoma (ARMS) were obtained using a detergent-enzymatic protocol. Scaffolds’ characteristics were investigated. Wild type mice were used as animal model for in vivo implantation on diaphragm and tibialis anterioris muscles. Samples were obtained at sequential timepoints and analysed with Histology, DNA quantification techniques, Immunofluorescence, Real-time PCR. Results. Decellularized ECM scaffold were obtained from each tissue. Moreover, their ECM maintained ultrastructure and composition. Implantation in vivo showed a regeneration of new, centre nucleated myofibers when muscle scaffold was used. No significant regeneration was observed with other scaffolds. With muscle implants, macrophagic response was present and characterized by organized distribution of cells. Conclusions. The decellularization protocol used in this study demonstrated to be effective in maintaining ECM properties even if in absence of cells. Pro-regenerative results obtained only with implantation of muscle-derived scaffolds underline the importance of tissue-specificity in order to obtain the ideal material to repair muscular defects. Premesse. Il trattamento della perdita di sostanza muscolare dovuta a traumi, resezioni chirurgiche o malformazioni rappresenta ancora una sfida in ambito medico. In passato sono stati creati diversi bioscaffold che potessero sostituire il tessuto muscolare ma i risultati sono stati poco soddisfacenti a causa del mancato stimolo alla rigenerazione tissutale e del mancato recupero funzionale. Alcuni studi hanno hanno esaminato le potenzialità rigenerative di bioscaffold derivati da matrice extracellulare di muscolo scheletrico. In ambito di ingegneria tissutale risulta sempre più importante la specificità tissutale dello scaffold. Questo studio mette a confronto il potenziale rigenerativo di scaffold tessuto-specifici e non in un modello di perdita di sostanza muscolare. In particolare vengono studiati i meccanismi di rigenerazione muscolare e la risposta macrofagica. Materiali e Metodi. Utilizzando un protocollo di decellularizzazione detergente-enzimatico, sono stati ottenuti da modello murino scaffold di matrice extracellulare di cute, intestino, rabdomiosarcoma. Di tali scaffold sono state studiate le caratteristiche intrinseche. Come modello animale è stato utilizzato il topo wild type. Gli scaffold sono stati impiantati chirurgicamente a livello del diaframma e del muscolo tibiale anteriore. I campioni, prelevati a timepoints diversi, sono stati esaminati con istologia, quantificazione del DNA, Immunofluorescenza, Real-Time PCR. Risultati. E' stato possibile ottenere scaffold di matrice extracellulare decellularizzata da ciascun tessuto esaminato. La struttura e la composizione della matrice extracellulare è stata preservata nonostante il trattamento di decellularizzazione. L'applicazione in vivo di scaffold derivati da muscolo ha indotto la rigenerazione di nuove fibre muscolari centro-nucleate. L'applicazione in vivo degli scaffold derivati dagli atri tessuti non ha condotto a rigenerazione tissutale. Una volta applicato lo scaffold derivato dal muscolo la risposta macrofagica è stata significativa e caratterizzata da una distribuzione regolare delle cellule. Conclusioni- Il protocollo di decellularizzazione utilizzato in questo studio è risultato efficace nell'ottenere matrici extracellulari decellularizzate pur preservando le caratteristiche della matrice stessa. Lo stimolo rigenerativo ottenuto solamente mediante impianto di matrice muscolare sottolinea l'importanza della specificità tissutale nell'ottica di ottenere un valido sostituto in caso di danno con perdita di sostanza.

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28

Harbron, Janetta. "The association between genotype and BMI, health and lifestyle indicators as well as weight loss outcomes in overweight/obese Caucasian adults." Thesis, Stellenbosch : University of Stellenbosch, 2011. http://hdl.handle.net/10019.1/6478.

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Thesis (PhD (Physiological Sciences))--University of Stellenbosch, 2011. Includes bibliography. ENGLISH ABSTRACT: Genetic screening to improve obesity treatment outcomes is available despite the lack of conclusive evidence, specifically for Caucasian South Africans, in this regard. The aim of this study was to investigate the association between genotype (seven polymorphisms) and body mass index (BMI), health and lifestyle indicators in a cross-sectional sample of overweight/obese Caucasian adults (n=133), as well as the association between genotype and weight loss outcomes following an intervention (n=88) using a quasi experimental study design (time-series). The intervention consisted of a 24-week conservative weight loss programme that included dietary, physical activity and behavioural components. The primary null hypothesis for the cross-sectional sample, namely that there is no association between genotype and BMI, has not been rejected. A number of the secondary/exploratory hypotheses were rejected of which the most plausible associations (based on support by the literature and a physiological basis for the findng) are: 1) the mutant TT homozygotes of the GNB3 C825T polymorphism may have a higher risk to develop the metabolic syndrome (MetS) as they had significantly higher fasting triglyceride and glucose levels, a higher number of traits that met the diagnostic cut-off criteria for MetS and higher number of these subjects was diagnosed with MetS compared to the wild-type C-allele carriers; and 2) subjects with mutant alleles of either the FTO rs1421085 or rs17817449 polymorphisms may have poorer eating behaviours (a higher rigid control, habitual and emotional disinhibition, perceived hunger and internal locus for hunger) and higher intake of high-fat foods. The primary null hypothesis for the intervention sample, namely that there is no association between genotype and weight loss outcome, was not rejected for the FABP2 Ala54Thr, INSIG2 rs7566605, FTO rs1421085, ADRB3 Trp64Arg and GNB3 C825T polymorphisms. However, it was rejected in some instances indicating the following associations: 1) The wild-type TT homozygotes of the FTO rs17817449 polymorphism lost significantly more weight during the first two months of the program compared to the mutant allele carriers (this is a novel finding); 2) The wild-type Arg16Arg homozygotes of the ADRB2 Arg16Gly polymorphism lost significantly more weight during the first month of the program compared to the mutant allele carriers (this finding is supported by one other intervention study); 3) Subjects with a mutant C-allele of the INSIG2 rs7566605 polymorphism and a mutant Gly16-allele of the ADRB2 Arg16Gly polymorphism lost significantly less weight over the six month intervention period (this is a novel genegene interaction finding). A number of secondary/exploratory hypotheses were rejected, of which the most plausible finding include that the improvement in emotional disinhibition in the wild-type TT subjects of the FTO rs1421085 polymorphism was associated with a more pronounced decrease in BMI over the six month weight loss period. The integration of the results from this study with the literature indicates that there is insufficient evidence at this stage for genetic screening of the polymorphisms investigated in this study and the provision of evidence-based personalized recommendations for weight loss in obese individuals. It is recommended that these associations should be viewed as priority in future research. AFRIKAANSE OPSOMMING: Genetiese sifting om die resultate van vetsug behandeling te verbeter is beskikbaar ten spyte van ‘n tekort aan genoegsame bewyse, spesifiek ten opsigte van Kaukasiërs van Suid-Afrika. Die doel van hierdie studie was om die assosiasie tussen genotipe (sewe polimorfismes) en liggaamsmassa indeks (LMI), gesondheid en lewenstyl indikatore in ‘n dwarssnit (cross-sectional) steekproef van oorgewig/vetsugtige Kaukasiër volwassenes (n=133) te ondersoek, asook die assosiasie tussen genotipe en gewigsverlies uitkomste na afloop van ‘n intervensie (n=88) in ‘n kwasi-eksperimentele studie ontwerp (tydreeks). Die intervensie het bestaan uit ‘n 24-week konserwatiewe gewigsverlies program met dieet, fisieke aktiwiteit en gedragskomponente. Die primêre nul hipotese vir die dwarsnit steekproef, naamlik dat daar geen assosiasie tussen genotipe en LMI is nie, is nie verwerp nie. ‘n Aantal sekondêre/spekulatiewe hipotesis is verwerp waarvan die mees geloofwaardige assosiasies (gebasseer op ondersteuning van die literatuur en ‘n fisiologiese basis vir die bevinding) die volgende insluit: 1) die mutante TT homosigote van die GNB3 C825T polimorfisme het moontlik ‘n hoër risiko vir die ontwikkeling van die metaboliese sindroom (MetS) aangesien hulle betekenisvolle hoër vastende trigliseriede en glukose vlakke gehad het, ‘n grooter aantal kenmerke gehad het wat aan die diagnostiese afsnykriteria vir MetS voldoen en ‘n grooter aantal van hierdie persone was met MetS gediagnoseer in vergelyking met die wilde-tipe C-alleel draers; en 2) persone met die mutante allele van die FTO rs1421085 of rs17817449 polimorfismes het moontlik ‘n swakker eetgedrag (‘n hoër rigiede kontrole, gewoonte en emosionele disinhibisie, waarneembare honger en interne lokus van honger) en ‘n hoër inname van hoë-vet voedsel. Die primêre nul hipotese vir die intervensie steekproef, naamlik dat daar geen assosiasie tussen genotipe en gewigsverlies uitkomste is nie, is nie vir die FABP2 Ala54Thr, INSIG2 rs7566605, FTO rs1421085, ADRB3 Trp64Arg en GNB3 C825T polimorfismes verwerp nie. Dit was egter in sommige gevalle vir die volgende assosiasies verwerp: 1) Die wilde-tipe TT homosigote van die FTO rs17817449 polimorfisme het betekenisvol meer gewig in die eerste twee maande van die program verloor in vergelyking met die mutante alleel draers (dit is ‘n nuwe bevinding); 2) Die wilde-tipe Arg16Arg homosigote van die ADRB2 Arg16Gly polimorfisme het betekenisvol meer gewig gedurende die eerste maand van die program verloor in vergelyking met die mutante alleel draers (hierdie bevinding word ondersteun deur een ander intervensie studie); 3) Persone met ‘n mutante C-alleel van die INSIG2 rs7566605 polimorfisme en ‘n mutante Gly16-allele van die ADRB2 Arg16Gly polimorfisme het minder gewig tydens die ses maande intervensie periode verloor (dit is ‘n nuwe geen-geen interaksie bevinding). ‘n Aantal sekondêre/ spekulatiewe hipoteses is verwerp, waarvan die mees geloofwaardigste bevinding insluit dat ‘n verbetering in emosionele disinhibisie van die wild-tipe TT persone van die FTO rs1421085 polimorfisme geassosieer was met ‘n meer prominente daling in LMI oor die ses maande gewigsverlies periode. Die integrasie van die resultate van hierdie navorsing met die literatuur dui aan dat daar op hierdie stadium onvoldoende bewyse vir genetiese sifting en die voorsiening van bewys-gebasseerde persoonlike aanbevelings vir gewigsverlies in vetsugtig individue bestaan vir die polimorfismes wat ondersoek is. Dit word aanbeveel dat hierdie assosiasies as prioriteit in toekomstige navorsing beskou moet word.

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29

Goley, George. "Investigation and Improvement of Occupational and Military Noise Exposure Guidelines: Evaluation of Existing and Modified Noise Exposure Metrics Using Historical Animal Data." University of Cincinnati / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1275924272.

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30

Wilber, Samantha. "North American River Otter (Lontra canadensis) Presence and Habitat Analysis in Florida as Compared to Historical Data." Scholar Commons, 2015. http://scholarcommons.usf.edu/etd/6052.

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North American river otters are considered common in the state of Florida, but their populations have not been studied since the 1980’s. Since that time, Florida’s human population has more than doubled, and many natural areas of Florida have been developed. The aim of this study was to determine the presence or absence of river otters at locations in Florida which they historically inhabited. Forty-six sample sites where otters were historically found were obtained from the Florida Museum of Natural History Mammals Master Database (FMNH MMD). These sites were condensed to two focus areas, in and around Alachua and Collier Counties, where the sites were most highly clustered. Each site was surveyed to determine the presence or absence of river otters and to determine the suitability of the site’s environment for otter habitation. Sites with favorable habitat features for otters were surveyed a second time. River otters were not found at any site. Only 9 of the 46 sites had permanent water and only 8 of those had other habitat features preferred by otters. Therefore, only 17.39% of sites that historically supported otters likely still have the ability to do so. Loss of water over time is most likely the result of human disturbances such as the draining, damming, and canalizing of wetlands. As a result of this loss of natural habitat, river otters have become increasingly common in urban areas wither preferred habitat features, even if they are man-made. The increased presence near humans may have led to the apparently inaccurate assumption that otters are common, and, therefore, do not need protection.

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31

Casali, André Oliveira. "Procedimentos metodológicos in situ na avaliação do teor de compostos indigestíveis em alimentos e fezes de bovinos." Universidade Federal de Viçosa, 2006. http://locus.ufv.br/handle/123456789/5740.

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Made available in DSpace on 2015-03-26T13:55:11Z (GMT). No. of bitstreams: 1 texto completo.pdf: 2632315 bytes, checksum: d33798ae37ec1db08e156eb3480efaca (MD5) Previous issue date: 2006-12-19 Conselho Nacional de Desenvolvimento Científico e Tecnológico This dissertation was elaborated based on two experiments related to evaluation of indigestible compounds in cattle feeds and feces. In the first experiment, the aim was to evaluate the contents of in situ indigestible neutral detergent fiber (iNDF) and the fibrous particles lost in aqueous environment in some ruminant feeds by using bags made with different textiles. The physical structure of the textiles was too evaluated. Samples of wheat bran (WB), soybean hulls (SH), corn silage (CS), and signal grass hay (SGH) were used. The bags for rumen incubation were made with nylon (50 μm); F57 (Ankon®); e non-woven textile (NWT 100 g/m²). The feed samples were ground (1 mm) and put in the bags (4 x 5 cm) (6 bags/textile), according to relationship 20 mg of dry matter/cm2 of surface. The bags were incubated in the rumen of a cow fed with a mixed diet (30% of concentrate) during 144 hours. After that, the bags were cleaning with tap water and treated with neutral detergent. The residue was assumed as iNDF. The iNDF contents in WB, SH and CS were similar for F57 and NWT (P>.05), being the results lower when nylon was used (P<.05). For the SGH samples all textiles produced different results (P<.05) being the lower contents obtained with nylon. The fibrous particles lost in aqueous environment was evaluated by cleaning the bags in warm tap water (39ºC) (10 bags/textile). The particles lost was significant for nylon (P<.05). This lost could be considered the cause of lower iNDF contents obtained by using nylon textile, once the microscopic evaluation did not show that rupture of textile occurred during incubation or neutral detergent extraction. In the second experiment, it were evaluated the effects of in situ incubation time and structure of particles on the estimates of indigestible fractions of dry matter (iDM), neutral detergent fiber (iNDF), and acid detergent fiber (iADF). Samples of corn grain, wheat bran, corn silage, elephant grass, sugarcane, signal grass hay, corn straw, and feces obtained from cattle fed high and low concentrate diets were used. The samples were ground through 1 mm, 2 mm, and 3 mm screen sieve and put in 4 x 5 cm non-woven textile bags (20 mg of dry matter/cm² of surface). The samples were divided in three groups, being each group incubated in the rumen of a crossbred heifer. The incubation procedure was conducted three times with the change of groups among animals. It were used the following incubation times: 0, 12, 24, 48, 72, 96, 120, 144, 168, 192, 216, 240, and 312 hours. The contents of iDM, iNDF, and iADF were evaluated sequentially in each bag. The degradation profiles were interpreted by a non-linear logistic model. The size of particles did not influence the estimates of iDM, iNDF, and iADF (P>.10). On the other hand, the particles size has altered (P<.10) the rumen degradation dynamic rates of DM for corn silage and corn grain; of NDF for sugarcane, corn silage, and corn straw; and ADF for sugarcane. For those samples, the particle size has been positively associated with the incubation time necessary to estimate de indigestible fraction. Incubation times of 240 hours for DM and NDF, and 264 hours for ADF were suggested for obtaining accurate estimates of indigestible fractions. The use of 2 mm particle size can increase the precision of estimates. A presente dissertação foi elaborada com base em dois experimentos relacionados à avaliação dos teores de compostos indigestíveis em alimentos e fezes bovinas. No primeiro experimento, objetivou-se avaliar os teores de fibra em detergente neutro indigestível (FDNi) obtidos por procedimento in situ e a perda de partículas fibrosas em meio aquoso de alguns alimentos para ruminantes por intermédio de sacos de diferentes tecidos. Avaliou-se, concomitantemente a estrutura física dos tecidos utilizados. Os alimentos avaliados foram: farelo de trigo (FT), casca de soja (CS), silagem de milho (SM) e feno de capim-braquiária (FB). Foram avaliados os tecidos: nylon (50 μm); F57 (Ankon®); e tecido não-tecido (TNT 100 g/m²). Os alimentos foram moídos (1 mm) e acondicionados em sacos de dimensão de 4 x 5 cm (6 amostras/tecido), obedecendo-se à relação de 20 mg de matéria seca/cm2 quadrado de superfície. Os sacos foram incubados por 144 horas no rúmen de uma vaca alimentada com dieta mista (30% de concentrado). Posteriormente, os sacos foram retirados, lavados em água corrente até o total clareamento, e tratados com detergente neutro, sendo o resíduo considerado como FDNi. Verificou-se similaridade entre os teores de FDNi obtidos com TNT e F57 (P>0,05), sendo estes superiores aos obtidos com nylon (P<0,05) para os alimentos FT, CS e SM. Para FB, os teores diferiram entre todos os tecidos (P<0,05), sendo os maiores valores observados para F57, os menores para o nylon, tendo o TNT apresentado posição intermediária. A perda de partículas fibrosas em meio aquoso foi avaliada por intermédio da lavagem dos sacos contendo os alimentos em água (39ºC) (10 amostras/tecido). Verificou-se perda de partículas (P<0,05) quando empregado o nylon como ambiente para avaliação das amostras, corroborando os menores teores de FDNi obtidos com este tecido. Observou-se, por intermédio de microscopia eletrônica de varredura, que a perda de partículas para o nylon deve ser atribuída à estrutura do tecido e não a possíveis danos causados durante os processos de incubação e extração com detergente. No segundo experimento, objetivou-se avaliar a influência do tempo de incubação in situ e da estrutura de partículas sobre as estimativas das frações indigestíveis da matéria seca (MSi), da fibra em detergente neutro (FDNi) e da fibra em detergente ácido (FDAi). Avaliaram-se amostras de: fubá de milho, casca de soja, farelo de trigo, farelo de soja, farelo de algodão, silagem de milho, capim-elefante, cana-de-açúcar, feno de capim-braquiária, palha de milho, fezes de bovinos alimentados com alto ou baixo nível de concentrados na dieta. As amostras foram processadas em moinho com peneiras de porosidade 1, 2 ou 3 mm, sendo acondicionadas (20mg de matéria seca/cm² de superfície) em sacos de tecido não-tecido (100g/m2) de dimensão 4 x 5 cm. Os materiais foram divididos em três grupos, sendo cada grupo incubado no rúmen de 3 novilhas mestiças (Holandês x Zebu). O procedimento de incubação foi repetido por três vezes, sendo que, a cada período procedeu-se à incubação dos grupos em animais distintos. Foram utilizados os tempos: 0, 12, 24, 48, 72, 96, 120, 144, 168, 192, 216, 240 e 312 horas. Os teores de MSi, FDNi e FDAi foram avaliados seqüencialmente, sendo os perfis de degradação interpretados por intermédio de modelo logístico não-linear. Verificou-se ausência de efeito do tamanho de partícula sobre as estimativas de MSi, FDNi e FDAi (P>0,10). Em relação aos efeitos dos tamanhos de partículas sobre a velocidade de degradação, verificaram-se efeitos significativos (P<0,10) para a silagem de milho e fubá de milho no tocante à MS; cana-de-açúcar, silagem de milho e palha de milho para a FDN; e cana-de-açúcar para a FDA. Para estas amostras, o tamanho de partícula associou-se positivamente ao tempo necessário para se estimar a fração indigestível. Tempos de incubação de 240 horas para MS e FDN e de 264 horas para FDA são recomendados para que se obtenham estimativas exatas das frações indigestíveis. O uso de partículas com 2 mm é recomendado em função da maior precisão das estimativas.

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32

Zemaryalai, Khatera. "Investigations into the roles of potassium channels in hair growth : studies confirming the presence of several ATP-sensitive potassium (K+ATP) channels in hair follicles and exploring their mechanism of action using molecular biological, cell culture, organ culture and proteomic approaches." Thesis, University of Bradford, 2010. http://hdl.handle.net/10454/4461.

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Hair disorders cause significant distress. The main, but limited, treatment for hair loss is minoxidil, an ATP-sensitive potassium (KATP) channel opener whose mechanism of stimulation is unclear. The regulatory component of KATP channels has three forms: SUR1, SUR2A and SUR2B which all respond to different molecules. Minoxidil only opens SUR2B channels, though SUR1 and SUR2B are present in human hair follicles. To expand our understanding, the red deer hair follicle model was used initially. Deer follicles expressed the same KATP channel genes as human follicles when growing (anagen), but no channels were detected in resting follicles. This reinforces the importance of KATP channels in active hair growth and the usefulness of the deer model. To assess whether SUR1 KATP channels are actually involved in human hair growth, the effects of a selective SUR1 channel opener, NNC55-9216, on scalp follicle growth in organ culture was examined. NNC55-9216 stimulated anagen; its effect was augmented by minoxidil. This creates the potential for more effective pharmaceuticals to treat hair loss via SUR1 channels, either alone or in combination with minoxidil. The dermal papilla plays a crucial regulatory role in hair follicle activity determining the type of hair produced. Minoxidil had no effect on dermal papilla cell proliferation, but altered the profile of proteins produced when assessed by proteomics. Further research into the roles of KATP channels and greater understanding of the significance of these protein changes should enhance our knowledge of hair biology and help the development of new, improved therapies for hair pathologies.

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Bech, Sàbat Gregori. "Factors of Non-Infectius Nature Affecting Late Embryonic/Early Foetal Loss in High Producing Dairy Cows: A Therapeutic Approach." Doctoral thesis, Universitat de Lleida, 2010. http://hdl.handle.net/10803/8323.

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Liberman, Diego Nique. "Avaliação do efeito do álcool em baixas concentrações na perda óssea alveolar em ratos wistar." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2009. http://hdl.handle.net/10183/31238.

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A relação entre o álcool e as doenças periodontais destrutivas tem sido avaliada em humanos através de estudos transversais e longitudinais na última década. As investigações apontam para resultados conflitantes sobre a influência do consumo de bebidas alcoólicas na progressão da periodontite. Em quatro estudos recentes realizados em ratos Wistar, o consumo de álcool com concentrações entre 10% e 30% esteve associado a uma maior perda óssea alveolar. Nestes estudos, os métodos de avaliação da perda óssea alveolar em estudos de modelo animal tem sido realizados de formas distintas, impedindo uma comparação direta em investigações que utilizaram diferentes concentrações de álcool. Contudo, a literatura tem correlacionado o consumo de concentrações moderadas de bebidas alcoólicas com uma melhora no sistema imunológico e uma redução em marcadores inflamatórios sistêmicos, reduzindo a ocorrência de eventos cardiovasculares e aterosclerose. O mecanismo de atuação do álcool nestes parâmetros parece ser ambíguo e dependente da dose, do padrão de consumo e de características individuais variáveis. Os resultados conflitantes sobre a relação entre consumo de bebidas alcoólicas e doença periodontal podem sugerir esse padrão bifásico do álcool. Não existem estudos em modelo animal que avaliaram o impacto da administração de concentrações menores de álcool sobre a perda óssea alveolar. A discussão acerca de metodologias adequadas para estudos em animais e interpretação dos resultados encontra-se limitada em poucos estudos. A presente tese propôs-se a avaliar o impacto do consumo de álcool numa concentração de 5% na destruição periodontal em um modelo de periodontite induzida por ligaduras em ratos Wistar. Uma comparação entre dois métodos distintos para a quantificação da perda óssea alveolar também foi realizada. Através de uma avaliação morfométrica, tanto linear quanto de área, verificou-se que os ratos que receberam etanol em uma concentração de 5% apresentaram uma menor perda óssea do que os ratos do grupo controle em dentes que não receberam ligadura (0.32±0.07 e 0.37±0.07 respectivamente;p=0.04). Apesar da menor perda óssea apresentada pelos ratos do grupo teste também nos dentes que haviam recebido ligadura, tais diferenças não foram estatisticamente significantes (0.78±0.14 e 0.84±0.18 respectivamente;p=0.14). Um valor de Correlação de Pearson de 0.98 foi encontrado estre os métodos de avalição de perda óssea alveolar lineares e de área, indicando de uma correlação quase perfeita.Sendo assim, ambos os métodos revelaram eficazes na detecção de alterações na crista óssea alveolar.Os resultados do presente estudo revelam que o consumo de álcool em concentrações moderadas (5%) pode inibir a perda óssea alveolar em ratos Wistar. The relationship between alcohol and periodontal disease have been evaluated in humans throughout cross-sectional and longitudinal studies in the last decade. The investigations have led to conflicting results about the influence of alcohol drinking on periodontitis progression. In four studies with Wistar rats, alcohol consumption in concentrations ranging between 10% to 30% was associated with greater alveolar bone loss. In these studies,different methods of bone loss evaluation have been used in animal model studies and it turns difficult to make a direct comparison between investigations that utilized different alcohol concentrations. However, the literature has associated moderate alcohol consumption with improvement in immunological status and reduction in inflammatory markers, reducing cardiovascular events and atherosclerosis. The mechanisms by which alcohol influences these parameters seems to be ambiguous and dependent of dose, pattern of consumption and individual characteristics. The conflicting results between beverage consumption and periodontal disease may suggest the biphasic pattern of alcohol. There aren’t studies in animal models that evaluated the impact of low alcohol concentrations on alveolar bone loss. Discussion about methodological issues and results interpretation in relation to studies in animals are restricted to few studies. The aim of the present thesis was to evaluate the impact of alcohol consumption in a concentration of 5% on periodontal breakdown in a ligature periodontitis-induced model. Also, a comparison between two distinct methods for bone loss assessment was evaluated. Linear and area morphometric evaluation revealed that rats receiving ethanol 5% presented less alveolar bone loss than rats in control group in unligated teeth (0.32±0.07 and 0.37±0.07 respectively;p=0.04). Despite the fact that rats in test group presented less alveolar bone loss even in ligated teeth when compared to controls,differences were no statistically significantly (0.78±0.14 and 0.84±0.18 respectively;p=0.14).A value of 0.98 were found in Pearson’s Correlation between linear and area morphometric methods of evaluating alveolar bone loss indicating an almost perfect correlation. Both methods were reliable for detecting alterations in alveolar bone crest. The results of the present study revealed that alcohol consumption in moderate concentrations (5%) may inhibit alveolar bone loss in Wistar rats.

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Edgel, Robert John. "Habitat Selection and Response to Disturbance by Pygmy Rabbits in Utah." BYU ScholarsArchive, 2013. https://scholarsarchive.byu.edu/etd/3928.

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The pygmy rabbit (Brachylagus idahoensis) is a sagebrush (Artemisia sp.) obligate that depends on sagebrush habitats for food and cover throughout its life cycle. Invasive species, frequent fires, overgrazing, conversion of land to agriculture, energy development, and many other factors have contributed to recent declines in both quantity and quality of sagebrush-steppe habitats required by pygmy rabbits. Because of the many threats to these habitats and the believed decline of pygmy rabbit populations, there is a need to further understand habitat requirements for this species and how they respond to disturbance. This study evaluated habitat selection by pygmy rabbits in Utah and assessed response of this small lagomorph to construction of a large-scale pipeline (i.e. Ruby pipeline) in Utah. We collected habitat data across Utah at occupied sites (pygmy rabbit occupied burrows) and compared these data to similar measurements at unoccupied sites (random locations within sagebrush habitat where pygmy rabbits were not observed). Variables such as horizontal obscurity, elevation, percent understory composed of sagebrush and other shrubs, and sagebrush decadence best described between occupied (active burrow) and unoccupied (randomly selected) sites. Occupied sites had greater amounts of horizontal obscurity, were located at higher elevations, had greater percentage of understory comprised of sagebrush and shrubs, and had less decadent sagebrush. When considering habitat alterations or management these variables should be considered to enhance and protect existing habitat for pygmy rabbits. The Ruby pipeline was a large-scale pipeline project that required the removal of vegetation and the excavation of soil in a continuous linear path for the length of the pipeline. The area that was disturbed is referred to as the right of way (ROW). From our assessment of pygmy rabbit response to construction of the Ruby pipeline, we found evidence for habitat loss and fragmentation as a result of this disturbance. The size of pygmy rabbit space-use areas and home ranges decreased post construction, rabbits shifted core-use areas away from the ROW, and there were fewer movements of collared rabbits across the ROW. Mitigation efforts should consider any action which may reduce restoration time and facilitate movements of rabbits across disturbed areas.

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Frederico, Canisso Igor. "Studies on Equine Placentitis." UKnowledge, 2014. http://uknowledge.uky.edu/gluck_etds/21.

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Two types of placentitis were studied: ascending and nocardioform placentitis. Although the first diagnosis of nocardioform placentitis was made three decades ago, little is known about the disease, due to the lack of an experimental model. In attempt to develop a research model, Crossiela equi was inoculated through intrauterine, intravenous, intrapharyngeal, and oral routes, but none of the routes resulted in nocardioform placentitis. This may indicate that unidentified factors may play a role in disease pathogenesis and that simple presence of bacteria is not sufficient to induce nocardioform placentitis. The second and major component of this dissertation involved the identification of diagnostic markers for placentitis. Because ascending bacterial placentitis is readily and predictably induced using existing experimental models, this model was used to identify diagnostic markers for placentitis in maternal plasma and fetal fluids. Three potential biomarkers were examined: acute phase inflammatory proteins, steroid hormones produced by the fetoplacental unit, and protein composition of the fetal fluids. Of the three acute phase proteins investigated, serum amyloid A and haptoglobin but not fibrinogen increased in association with experimentally induced ascending placentitis. Androgens and progestins appear to be poor markers for placentitis. Serum estradiol 17β concentrations were reduced in mares with experimentally induced placentitis and appear to be a good marker for placentitis in mares. Different methods were used to study the protein composition of the fetal fluids. Alpha-fetoprotein was characterized as a major protein present in the equine fetal fluids, and this protein was elevated in plasma of mares with placentitis. In another study, using a high-throughput proteomic technique several new proteins were characterized in the amniotic and allantoic fluids of mares carrying normal pregnancies, and several previously uncharacterized proteins were detected in the allantoic fluid of mares with placentitis. Three secreting proteins were elevated in allantoic fluid of mares with experimentally induced ascending placentitis.

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37

Gayer, Whitney Anne. "Water Transport in the Lateral Line Canal of the Intertidal Fish Xiphister mucosus (Girard 1858) and Its Significance to Evaporative Water with Preliminary Observations of the Metabolic Consequences of Water Loss." PDXScholar, 2018. https://pdxscholar.library.pdx.edu/open_access_etds/4089.

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The lateral line canal system is a sensory organ found in all teleost fish that has a wide range of morphological variation. Variation in morphology may often be the result of evolutionary necessity where the need for function dictates form. Xiphister mucosus is an amphibious Stichaeid fish that inhabits the rocky intertidal zone of the northeastern Pacific Ocean. The rocky intertidal is considered an extreme environment where crashing waves and ebbing tides may require the specialization of adaptations for surviving the many abiotic stressors encountered there. The lateral line trunk canal of Xiphister is regarded as unique among teleosts with multiple, branching, zigzag shaped canals that are morphologically complex. The X. mucosus canal was found to not serve as a mechanosensory organ, rather the findings presented here suggest a new role as a water transport organ. This may be an exaptation to help X. mucosus avoid desiccation during low tides when the fish remain upon the rocky shore and exposed to dehydration. While emersed, Xiphister relies on cutaneous respiration as its primary means of aerial respiration.

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38

Lord, Linda K. "Epidemiological study of Ohio animal shelters and lost and found pet population issues." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1163187060.

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39

Guterres, Acacio da Costa. "The effects of different cutting heights, mulching and burning on the control of bellyache bush (jatropha gossypifolia L.) applicable in East Timor." Thesis, Curtin University, 2008. http://hdl.handle.net/20.500.11937/2357.

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Since bellyache bush invaded to East Timor it has significantly reduced crop and animal production and consequential loss of income from farm enterprises. Methods of control of bellyache bush chosen should be appropriate to the poor economic position of the farmers. An integrated method of controlling bellyache bush involving slashing combined with mulching and or burning is low cost and is widely used by the Timorese farmers. Although these practices are commonly used to control weeds, there are still many problems that appear in the field during and after weed control. For instance, rapid regeneration of cut stems and production of less fuel than mixed stands to support burning management.Therefore, the objective of this study is to investigate mechanical control such as cutting stems at different heights and cutting stems at different heights in combination with mulch, handpulling and mulching of small plants and mulching of seedlings. This study also investigates bellyache bush properties as a fuel for burning management in the late dry season to control its infestations.Mechanical control of bellyache bush plants was undertaken south of Darwin at Acacia (12º45’S, 131º09’E) which has an annual average rainfall of 1588.1 mm and Channel Island (12º33’S, 130º51’E) which has annual rainfall of 1713.9 mm. This study was conducted from January 2007 to February 2008. All bellyache bush plants were cut off at different heights according to treatment 0cm (ground level), 10cm, 20cm, 30cm, 40cm and uncut plants considered as a control.The results indicated that all cutting treatments achieved 100% mortality under low canopy cover, irrespective of season. While, under high canopy cover bellyache bush plants only achieved 100% mortality if cut at 0cm and 10cm height. Stems cut at 20cm, 30cm and 40cm heights re-sprouted in the dry season. Hand-pulling completely killed small plants while mulching did not. Mulching achieved a partial kill of seedlings however it stimulated seedling emergence in the wet season, irrespective of site.The use of bellyache bush as a fuel for burning management was studied. The study was undertaken at Channel Island, Acacia and Katherine (14º22’S, 132º09’E). The latter has a mean annual rainfall of 875 mm. All bellyache bush plants in the plot were cut in May. Five 1m x 1m quadrat samples were selected within a 10m x 10m plot to measure wet weight and dry weight for the curing rate calculation. In addition, 15 of the cut stems were randomly selected to measure re-sprouting. From five randomly selected 25cm x 25 cm quadrat samples were taken to calculate the weight of fine fuel (less than 6mm in diameter), medium (6mm-25mm) and coarse (greater than 25mm). Heat yield of fuel combustion of this material was calculated by using a bomb calorimeter (As 10-38.5 leco 350 calorimeters).The results indicated that cut stems of bellyache bush from a low canopy cover site had 7 percent moisture content while stems from a high canopy cover site had a 66 percent moisture content by the end of the dry season. The proportion of these stems in the site with low canopy cover re-sprouted significantly less than those in the high canopy cover site. The fuel load at bellyache bush monoculture had less fine, medium and coarse fuel compared with tropical savanna fuel. However, results from this study indicated that it had a similar heat yield of combustion to other plants in the tropical savanna.A study of the use of fire as a control tool for bellyache bush was undertaken at Acacia and Katherine from May 2007 to February 2008. This study was carried out on established plants of bellyache bush. The experiment was undertaken in three 10m X 10m plots at each of the two sites. The experiment consisted of three treatments namely: cutting stems at 30 cm and followed by burning, uncut plants plus burning and unburnt plants considered as a control. Each of 20 pieces of bellyache bush stems were randomly selected for fine 0-6 mm, medium 6-25 mm and coarse 25 mm fuel. All these pieces were weighed before and after fire to calculate fuel consumption. Fire intensity was calculated by using Byram’s fire intensity equation. Fifteen soil temperature sensors were buried under uncut plants before burning. After burning all soil temperature sensors were dug out the temperature read and used to calculate fire temperature. Plant mortality was calculated by counting live bellyache bush plants before and after fire. Seed germination and seed recruitment was calculated by counting all seedlings within five 1m x 1m randomly chosen quadrats.The results show that fire consumed all bellyache bush stems in the late dry season burning. Fire intensity of bellyache bush fuels was quite low compared to other tropical savanna fuel. Soil temperatures ranged between 54.17ºC to 126.13ºC. All bellyache bush plants were completely killed by the fire treatment, but fire stimulated seedling emergence in the following wet season. It was concluded from the results of the experiments that mechanical control slashing system may provide a suitable fuel for the burning management if cut early in the dry season. By late in the dry season bellyache bush plants cut early in the dry season have a low moisture content are completely cured and able to support fire spread of adequate intensity to destroy the plants.

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Muller, Fernando. "Volatilização de amônia com o uso de dejetos de suínos com pH modificado." Universidade Estadual do Oeste do Paraná, 2018. http://tede.unioeste.br/handle/tede/3950.

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Submitted by Edineia Teixeira (edineia.teixeira@unioeste.br) on 2018-09-26T13:43:20Z No. of bitstreams: 2 Fernando_Muller_2018.pdf: 512041 bytes, checksum: 2ff86626a282d8b0ea9a5d679b8fd5a4 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Made available in DSpace on 2018-09-26T13:43:20Z (GMT). No. of bitstreams: 2 Fernando_Muller_2018.pdf: 512041 bytes, checksum: 2ff86626a282d8b0ea9a5d679b8fd5a4 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-03-27 In western Paraná the production of pigs in feedlot system is in a large scale, resulting in a wide production of manure with a high power of environmental pollution if not treated correctly. The use of this manure as biofertilizers may be an interesting alternative for the agricultural sector by providing nutrients to plants, especially nitrogen. In addition, the biofertilizer can improve soil fertility by increasing its organic matter. However, after the application of nitrogen to the soil, gaseous losses of this nutrient may occur, denominated ammonia volatilization, which can be intensified by different factors. Thus, the objective of this work was to evaluate the fertilization of soybean with liquid swine manure and the loss of nitrogen by volatilization after the application of it with different pHs. The work was conducted in two experiments. The first one was conducted in the 2015/2016 under no-tillage system with soybean crop. On the day of sowing, the treatments were composed of three doses of liquid swine manure (48; 96 and 144 m3 ha-1), plus additional treatments, which were the control (without fertilization) and a treatment with mineral fertilization (300 kg ha-1 of NPK formulation 04-30-10). The productivity of grains, green stems, heights of plants and one hundred grain mass were analyzed. The second work was conducted in a greenhouse during the period from October to December 2017. The ammonia volatilization was evaluated according to the adjusted pH of the liquid swine manure, being 3.0; 4.0; 5.0; 6.0 and 7.4 (natural manure). Further, two additional treatments were evaluated: natural manure + agricultural gypsum and the control (without application of manure). In order to capture the volatilized ammonia, Sale type collectors were used, with a static free semi-open chamber. The volatilization flow, accumulated volatilization and percentage of ammonia loss were analyzed. The mineral fertilization of soybean crop can be replaced by fertilization with liquid swine manure, mainly in high fertility soils. The fertilization with 48 m³ ha-1 was able to supply the nutritional need of the soybean crop according to the productivity obtained. The application of liquid swine manure with natural pH (7,4) provided high losses of ammonia, around 46 % higher. With the acidification of the manure by adjusting the pH around 3 to 5, a great reduction to 5 % of loss of nitrogen by volatilization was observed. No oeste do Paraná a produção de suínos em sistema de confinamento é de grande escala, resultando em alta produção de dejetos, com grande potencial para poluição ambiental se não tratados de forma correta. A utilização desses dejetos como biofertlizante pode ser uma alternativa interessante para o setor agrícola pelo fornecimento de nutrientes às plantas, principalmente o nitrogênio. Além do mais, a aplicação do biofertilizante pode melhorar a fertilidade do solo pelo incremento da matéria orgânica. Entretanto, após a aplicação de nitrogênio no solo podem ocorrer perdas gasosas desse nutriente, principalmente sob a forma de amônia. Esse processo é denominado volatilização e pode ser intensificado por diferentes fatores. Assim, o trabalho teve por objetivo avaliar a adubação da soja com dejetos líquidos de suínos e a perda de nitrogênio por volatilização após a aplicação dos dejetos com diferentes pHs. O trabalho foi conduzido em dois experimentos. O primeiro foi conduzido na safra 2015/2016 em sistema de plantio direto com a cultura da soja. No dia da semeadura foram aplicados os tratamentos compostos por três doses de dejeto líquido de suínos (48; 96 e 144 m3 ha-1), mais os tratamentos adicionais, que foram a testemunha (sem adubação) e um tratamento com adubação mineral (300 kg ha-1 do formulado NPK 04-20-10). Foram analisados a produtividade de grãos, hastes verdes, alturas de plantas e massa de cem grãos. O segundo trabalho foi conduzido em casa de vegetação durante o período de outubro a dezembro de 2017. Foi avaliada a volatilização da amônia em função dos pHs ajustados do dejeto líquido de suínos, sendo 3,0; 4,0; 5,0; 6,0 e 7,4 (natural do dejeto). Além disso, foram avaliados dois tratamento adicionais: dejeto natural + gesso agrícola e a testemunha (sem aplicação de dejeto). Para captação da amônia volatilizada foram utilizados coletores do tipo Sale, com câmara semiaberta livre estática. Foram analisados o fluxo de volatilização; volatilização acumulada e porcentagem de perda de amônia. A adubação mineral da cultura da soja pode ser substituída pela adubação com dejeto líquido de suínos, principalmente em solos de fertilidade alta. A adubação com 48 m³ ha-1 de dejeto líquido de suínos foi capaz de suprir a necessidade nutricional da cultura da soja conforme a produtividade obtida. A aplicação do dejeto líquido de suínos com pH natural (7,4) proporcionou altas perdas de amônia, em torno de 46 %. Com a acidificação dos dejetos ajustando-se o pH em torno de 3 a 5 houve e redução para 5 % de perda de nitrogênio por volatilização.

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41

Schenkel, André Cavalheiro. "Relação entre condição corporal de fêmeas suínas ao primeiro parto e ao desmame e a produção de leitões no segundo parto." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2007. http://hdl.handle.net/10183/10415.

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O objetivo deste estudo foi avaliar a influência do número de leitões paridos e desmamados no primeiro parto, das reservas corporais ao parto e a perda das reservas corporais durante a lactação sobre a produção de leitões no segundo parto. Foram analisadas 1222 fêmeas que chegaram ao segundo parto sem interrupções como retorno ao estro, abortamento ou vazias ao parto. Foram medidos o peso corporal, espessura de toucinho (ET) e escore corporal visual (ECV), no máximo 24 horas pós-parto e no dia do desmame. Foram calculados a gordura e a proteína corporal ao parto e ao desmame para posteriormente serem obtidos os valores com relação às perdas destas reservas. O total de leitões nascidos no primeiro e no segundo partos e o número de leitões desmamados foram analisados de acordo com as características corporais e produtivas das fêmeas no primeiro parto e primeiro desmame. O tamanho de leitegada no primeiro e no segundo partos foram, respectivamente 12,4 leitões e o de 9,7 leitões nascidos totais. Na média as fêmeas apresentaram redução de 18,6 kg (9%) de peso corporal, 3,1mm de ET e 0,8 de ECV durante a lactação. O tamanho da leitegada no segundo parto não diferiu entre as classes das variáveis, peso, ET, ECV, gordura e proteína corporal no primeiro parto (P>0,05). As fêmeas com peso acima de 178kg, ET (≥16), ECV (≥3,0) e gordura corporal (≥21%) ao desmame tiveram maior leitegada no segundo parto e menor diferença no número de nascidos entre o primeiro e segundo parto (P<0,05). Fêmeas com maior percentual de proteína corporal ao desmame (≥15%) tiveram maior número de leitões nascidos na segunda leitegada. Houve maior diminuição no tamanho da segunda leitegada nas fêmeas com perdas de peso corporal acima de 10% (P<0,05). Perdas de proteína ou de gordura corporal acima de 10% e de 23%, respectivamente implicaram na maior diminuição no número de leitões nascidos no segundo parto (P<0,05). A perda de reservas corporais durante a lactação de primíparas influencia a redução do tamanho da leitegada no segundo parto. The aim of this study was to evaluate the influence of body reserves at farrowing and the corporal reserves losses during the first lactation on the second litter size. A number of 1222 females that reached the second parity without interruptions as return to estrus, abortion or failing to farrow were analyzed. Measurements of body weight, backfat thickness (BT) and corporal condition (CC) were taken within 24-hours after farrowing and on the weaning day. Sow body fat and protein mass, at first farrowing and first weaning, were calculated and the values of these reserves losses were estimated. The total piglets at first and second farrowing and the number of weaned piglets were analyzed according to the females corporal and productive characteristics at first farrowing and first weaning.Litter size at first and second farrowing were respectively 12.4 and 9.7 total born piglets. In the average, the females demonstrated a reduction of 18.6 kg (9%) in body weight, 3.1mm BT and 0.8 CC during lactation. Second litter size did not differ between the categories body weight, BT, CC, body fat and body protein at first farrowing (P>0.05). Females with more than 178kg, BT (≥16), ECV (≥3.0) and body fat (≥21%) at weaning had largest second litters and less differences in the number of piglets born between first and second farrowing (P<0.05). Sow body protein mass at weaning (≥15%) had a higher effect on the number of piglets produced in the second litter. Females with weight losses during lactation above 10% showed the greatest reduction in second litter size (P<0.05). Protein or fat mass losses above 10% and 23%, respectively resulted in a high reduction in the number of total born piglets in second litter (P<0.05).Looses of corporal reserves during the first lactation influences the reduction in the second litter size.

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42

Guterres, Acacio da Costa. "The effects of different cutting heights, mulching and burning on the control of bellyache bush (jatropha gossypifolia L.) applicable in East Timor." Curtin University of Technology, Faculty of Science and Engineering, Muresk Institute, 2008. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=119757.

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Since bellyache bush invaded to East Timor it has significantly reduced crop and animal production and consequential loss of income from farm enterprises. Methods of control of bellyache bush chosen should be appropriate to the poor economic position of the farmers. An integrated method of controlling bellyache bush involving slashing combined with mulching and or burning is low cost and is widely used by the Timorese farmers. Although these practices are commonly used to control weeds, there are still many problems that appear in the field during and after weed control. For instance, rapid regeneration of cut stems and production of less fuel than mixed stands to support burning management. Therefore, the objective of this study is to investigate mechanical control such as cutting stems at different heights and cutting stems at different heights in combination with mulch, handpulling and mulching of small plants and mulching of seedlings. This study also investigates bellyache bush properties as a fuel for burning management in the late dry season to control its infestations. Mechanical control of bellyache bush plants was undertaken south of Darwin at Acacia (12º45’S, 131º09’E) which has an annual average rainfall of 1588.1 mm and Channel Island (12º33’S, 130º51’E) which has annual rainfall of 1713.9 mm. This study was conducted from January 2007 to February 2008. All bellyache bush plants were cut off at different heights according to treatment 0cm (ground level), 10cm, 20cm, 30cm, 40cm and uncut plants considered as a control. The results indicated that all cutting treatments achieved 100% mortality under low canopy cover, irrespective of season. While, under high canopy cover bellyache bush plants only achieved 100% mortality if cut at 0cm and 10cm height. Stems cut at 20cm, 30cm and 40cm heights re-sprouted in the dry season. Hand-pulling completely killed small plants while mulching did not. Mulching achieved a partial kill of seedlings however it stimulated seedling emergence in the wet season, irrespective of site. The use of bellyache bush as a fuel for burning management was studied. The study was undertaken at Channel Island, Acacia and Katherine (14º22’S, 132º09’E). The latter has a mean annual rainfall of 875 mm. All bellyache bush plants in the plot were cut in May. Five 1m x 1m quadrat samples were selected within a 10m x 10m plot to measure wet weight and dry weight for the curing rate calculation. In addition, 15 of the cut stems were randomly selected to measure re-sprouting. From five randomly selected 25cm x 25 cm quadrat samples were taken to calculate the weight of fine fuel (less than 6mm in diameter), medium (6mm-25mm) and coarse (greater than 25mm). Heat yield of fuel combustion of this material was calculated by using a bomb calorimeter (As 10-38.5 leco 350 calorimeters). The results indicated that cut stems of bellyache bush from a low canopy cover site had 7 percent moisture content while stems from a high canopy cover site had a 66 percent moisture content by the end of the dry season. The proportion of these stems in the site with low canopy cover re-sprouted significantly less than those in the high canopy cover site. The fuel load at bellyache bush monoculture had less fine, medium and coarse fuel compared with tropical savanna fuel. However, results from this study indicated that it had a similar heat yield of combustion to other plants in the tropical savanna. A study of the use of fire as a control tool for bellyache bush was undertaken at Acacia and Katherine from May 2007 to February 2008. This study was carried out on established plants of bellyache bush. The experiment was undertaken in three 10m X 10m plots at each of the two sites. The experiment consisted of three treatments namely: cutting stems at 30 cm and followed by burning, uncut plants plus burning and unburnt plants considered as a control. Each of 20 pieces of bellyache bush stems were randomly selected for fine 0-6 mm, medium 6-25 mm and coarse 25 mm fuel. All these pieces were weighed before and after fire to calculate fuel consumption. Fire intensity was calculated by using Byram’s fire intensity equation. Fifteen soil temperature sensors were buried under uncut plants before burning. After burning all soil temperature sensors were dug out the temperature read and used to calculate fire temperature. Plant mortality was calculated by counting live bellyache bush plants before and after fire. Seed germination and seed recruitment was calculated by counting all seedlings within five 1m x 1m randomly chosen quadrats. The results show that fire consumed all bellyache bush stems in the late dry season burning. Fire intensity of bellyache bush fuels was quite low compared to other tropical savanna fuel. Soil temperatures ranged between 54.17ºC to 126.13ºC. All bellyache bush plants were completely killed by the fire treatment, but fire stimulated seedling emergence in the following wet season. It was concluded from the results of the experiments that mechanical control slashing system may provide a suitable fuel for the burning management if cut early in the dry season. By late in the dry season bellyache bush plants cut early in the dry season have a low moisture content are completely cured and able to support fire spread of adequate intensity to destroy the plants.

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43

Sun, Huawei. "Theoretical and experimental study of a high rise hog building for improved utilization and environmental quality protection." Columbus, Ohio : Ohio State University, 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1079066940.

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Thesis (Ph. D.)--Ohio State University, 2004. Title from first page of PDF file. Document formatted into pages; contains xii, 200 p.; also includes graphics (some col.). Includes abstract and vita. Advisor: Frederick C. Michel, Jr., Dept. of Food, Agricultural, and Biological Engineering. Includes bibliographical references (p. 173-181).

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44

Molon, Rafael Scaf de. "Patofisiologia de osteonecrose induzida por bisfosfonatos e inibidores de RANK-L /." Araraquara, 2016. http://hdl.handle.net/11449/138846.

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Orientador: Joni Augusto Cirelli Banca: Juliano Milanezi de Almeida Banca: Daniela Bazan Palioto Banca: Pedro Paulo Chaves de Souza Banca: Francisco Humberto Nociti Junior Resumo: A patogênese de osteonecrose dos maxilares (ONJ) e os fatores de risco ainda não estãototalmente elucidados e continuam sendo foco de contínuos estudos visando estabelecer umcorreto diagnóstico, prevenção e tratamento. Assim, os objetivos do presente estudo foram:(1) desenvolver em camundongos, um modelo experimental de ONJ induzido porbisfosfonatos (BPs) e inibidores de RANK-L associado a doença periodontal espontânea; (2)investigar neste modelo se a descontinuação desses medicamentos alteraria as característicasclinicas e radiográficas de osteonecrose e, (3) avaliar a influência da artrite reumatoide (AR)no agravamento de ONJ experimental. As análises em todos os estudos foram estabelecidaspor meio de avaliações radiográficas, por microtomógrafo, e histológicas. No primeiro estudo,foi estabelecido um novo modelo experimental animal utilizando-se diferentes medicamentosanti-reabsortivos, resultando em características clinicas semelhantes ao que ocorre emhumanos, ou seja, extensas áreas necróticas e com exposição óssea a cavidade oral. Osresultados do estudo 2 demonstraram que a descontinuação de OPG-Fc, um inibidor deRANK-L, mas não de BPs reverteu todas as características clinicas e radiográficas de ONJ.Além disso, os resultados do estudo 3 sugerem que a AR associada ao tratamento com altasdoses de BPs exacerba a incidência e a severidade de ONJ em camundongos. Com base nosachados do presente estudo, conclui-se que ONJ induzida por BPs e por ... (Resumo completo, clicar acesso eletrônico abaixo) Abstract: The pathogenesis of the osteonecrosis of the jaw (ONJ) and its risk factors still remain poorly understudied and continue to be the focus on ongoing studies to establish a proper diagnosis, prevention and treatment. Thus, the aims of this study were: (1) to develop in mice, an experimental model of osteonecrosis induced by bisphosphonates (BPs) and RANK-L inhibitors associated with spontaneously periodontal disease. Then, (2) using the same experimental model in mice, to investigate if the discontinuation of these drugs alters the clinical and radiographic features of ONJ. In addition, (3) the influence of systemic diseases such as rheumatoid arthritis (RA), and ONJ was assessed as a possible risk factor for worsening ONJ characteristics. The analyses in all studies were established through radiographic, by means of micro-computed tomography, and histological assessments. In the first study, a new experimental animal model using different antiresorptive drugs was established with clinical features similar to what occurs in humans, with extensive necrotic areas and exposed bone o the oral cavity. The results of the study 2 showed that discontinuing OPG-Fc, a RANK-L inhibitor, but not BPs reversed all the clinical and radiographic features of ONJ. Furthermore, the results of study 3 suggest that treatment with high doses of BPs associated with the presence of RA exacerbated the incidence and severity of ONJ in mice. These data evidenced that BPs and RANK-L inhibitors possess gr... (Complete abstract click electronic access below) Doutor

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45

Biswas, Tanushree. "A Spatio-Temporal Analysis of Landscape Change within the Eastern Terai, India : Linking Grassland and Forest Loss to Change in River Course and Land Use." DigitalCommons@USU, 2010. http://digitalcommons.usu.edu/etd/610.

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Land degradation is one of the most important drivers of landscape change around the globe. This dissertation examines land use-land cover change within a mosaic landscape in Eastern Terai, India, and shows evidence of anthropogenic factors contributing to landscape change. Land use and land cover change were examined within the Alipurduar Subdivision, a representative of the Eastern Terai landscape and the Jaldapara Wildlife Sanctuary, a protected area nested within Alipurduar through the use of multi-temporal satellite data over the past 28 years (1978 - 2006). This study establishes the potential of remote sensing technology to identify the drivers of landscape change; it provides an assessment of how regional drivers of landscape change influence the change within smaller local study extents and provides a methodology to map different types of grassland and monitor their loss within the region. The Normalized Difference Vegetation Index (NDVI) and a Normalized Difference Dry Index (NDDI) were found instrumental in change detection and the classification of different grasslands found inside the park based on their location, structure, and composition. Successful spectral segregation of different types of grasslands and their direct association with different grassland specialist species (e.g., hispid hare, hog deer, Bengal florican) clearly showed the potential of remote sensing technology to efficiently monitor these grasslands and assist in species conservation. Temporal analysis provided evidence of the loss of dense forest and grasslands within both study areas with a considerably higher rate of loss outside the protected area than inside. Results show a decline of forest from 40% in 1978 to 25% in 2006 across Alipurduar. Future trends project forest cover and grassland within Alipurduar to reduce to 15% and 5%, respectively. Within the Alipurduar, deforestation due to growth of tea industry was the primary driver of change. Flooding changed the landscape, but more intensely inside the wildlife preserve. Change of the river course inside Jaldapara during the flood of 1968 significantly altered the distribution of grassland inside the park. Unless, the direction of landscape change is altered, future trends predict growth of the tea industry within the region, increased forest loss, and homogenization of the landscape.

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Peralta, Felipe da Silva. "Indução de doença periodontal em ratos previamente expostos à ciclosporina A." Universidade de Taubaté, 2008. http://www.bdtd.unitau.br/tedesimplificado/tde_busca/arquivo.php?codArquivo=468.

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A Ciclosporina A (CsA) é o medicamento de escolha utilizado no controle da rejeição de órgãos em pacientes transplantados. Efeitos adversos associados ao fármaco, como alterações ósseas e o aumento gengival são fatores de risco para a doença periodontal. O objetivo do estudo foi avaliar o efeito da indução de doença periodontal no tecido ósseo, tecido epitelial e tecido conjuntivo de ratos previamente tratados com a CsA. Foram utilizados quarenta ratos Wistar, com 12 semanas de vida, divididos em quatro grupos (n=10): grupo Controle (GC); grupo Ciclosporina A (GCsA), administração de 10mg/kg de CsA durante sessenta dias a partir do início do experimento; grupo Ciclosporina A Ligadura (GCsAL), inserção da ligadura após trinta dias do início do experimento e administração de 10mg/Kg de CsA desde o início do experimento, durante sessenta dias; grupo Ligadura (GL), inserção da ligadura após trinta dias do início do experimento. Os animais foram sacrificados após sessenta dias por meio de perfusão cardíaca para a realização da análise histológica e histomorfométrica do tecido gengival e tecido ósseo, análise radiográfica do suporte ósseo periodontal e da densidade radiográfica e análise bioquímica da Fosfatase Alcalina. Os resultados foram submetidos à análise de variância (ANOVA, Tukey) a 5% e ao teste não paramétrico de Kruskal- Wallis. Os valores médios para GC (60.5 2.22%) e GCsAL (58.1 2.24%) foram equivalentes entre si para o suporte ósseo periodontal e diferentes de GCsA (55.0 4.44%) e GL (54.8 3.11%) (p=0.0007). Os valores médios da densidade radiográfica não apresentaram diferença estatística significativa (p=0.1776). Em relação à fosfatase alcalina, novamente não foi observada diferença significativa entre os grupos (p=0.2806). Os valores médios de células TRAP+ por grupo experimental, não apresentaram diferença estatística significativa (p=0.3995). Os valores médios para GC (0.29 0.03mm2) e GCsA (0.30 0.02mm2) foram equivalentes entre si para a área do ligamento periodontal e diferentes de GCsAL (0.43 0.17mm2) e GL (0.41 0.11mm2) (p=0.3994). Na área total do tecido gengival, os valores médios para GCsA (0.088 0.033mm2) e GL (0.101 0.034mm2) foram equivalentes entre si e diferentes de GC (0.053 0.020mm2) e GCsAL (0.146 0.047mm2) (p=0.000001). Na proporção área do conjuntivo e área total, os valores médios para GC (28.60 8.64%) foi equivalente ao GCsA (32.72 14.13%) e diferente do GCsAL (38.50 10.98%) e GL (37.70 7.49%) (p=0.0093). Em relação à proporção área do epitélio e área total, os valores médios para GC (71.39 8.64%) foi equivalente ao GCsA (67.27 14.13%) e diferente do GCsAL (61.49 10.98%) e GL (63.37 7.44%) (p=0.0142). Na proporção área do epitélio e área do conjuntivo, os valores médios para GC (2.80 1.13) foi equivalente ao GCsA (2.18 1,32) e diferente do GCsAL (1.89 1.17) e GL (1.81 0.80) (p=0.0334). Baseados nestes resultados pode-se concluir que a exposição prévia a CsA não modificou significativamente a evolução da doença periodontal induzida em ratos. Cyclosporine A (CsA) is the drug of choice used to prevent organ transplant rejection. Side effects associated to the drug, like bone alterations and gingival overgrowth are considered risk factors to periodontal disease. The objective of the present study was to evaluate the effect of periodontal disease on the bone tissue, epitelial tissue and connective tissue of the rats previously treated with CsA. Forty Wistar rats with 12 weeks were divided into four groups: Control Group (CG, n=10); CsA Group (CsAG, n=10), with CsA (10mg/kg) administration during 60 days since the beginning of the experiment; CsA and Ligature Group (CsALG, n=10), with ligature placement at 30 days after the beginning of the experiment with CsA administration during the whole period; and, Ligature Group (LG, n=10), with ligature placement at 30 days after the beginning of the experiment. After blood sample collection for the biochemical analysis of the Alkaline Phosphatase (PA) activity, the animals were sacrificed by intracardiac perfusion at 60 days after the beginning of the experiment. The mandibles were removed for histologic and histometric analyses of the gingival and bone tissues, and radiographic analysis of the alveolar bone support and density. The data were subjected to analysis of variance (ANOVA, Tuckey) at 5% and to the non-parametric test of Kruskal-Wallis. The mean percentage of alveolar bone support for the CG (60.5 2.22%) was similar to the CsALG (58.1 2.24%) and different to the CsAG (55.0 4.44%) and LG (54.8 3.11%) (p=0.0007). Bone density and PA activity were not statistically different among groups (p=0.1776, and p=0.2806, respectively). The mean values for TRAP+ cells were not statistically different among experimental groups (p=0.3995). The mean values of the periodontal ligament area for CG (0.29 0.03mm2) were similar to the CsAG (0.30 0.02mm2) and statistically different to the CsALG (0.43 0.17mm2) and to the LG (0.41 0.11mm2) (p=0.3994). With regards to the total area of the gingival tissue, the mean values for the CsAG (0.088 0.033mm2) and LG (0.101 0.034mm2) were similar between each other and statistically different to the CG (0.053 0.020mm2) and CsALG (0.146 0.047mm2) (p=0.000001). Regarding the proportion of connective tissue area to the total area, the mean value of the CG (28.60 8.64%) was similar to the CsAG (32.72 14.13%) and statistically different to the CsALG (38.50 10.98%) and to the LG (37.70 7.49%) (p=0.0093). In relation to the proportion of the epithelial tissue area to the total area, the mean value for the CG (71.39 8.64%) was similar to the CsAG (67.27 14.13%) and different to the CsALG (61.49 10.98%) and LG (63.37 7.44%) (p=0.0142). In the proportion of epithelial tissue area to the connective tissue area, the mean value for the CG (2.80 1.13) was similar to the CsAG (2.18 1.32) and different to the CsALG (1.89 1.17) and LG (1.81 0.80) (p=0.0334). Based on these results it can be concluded that previous exposure to CsA did not significantly modify the development of periodontal disease induced in rats.

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LANDIM, Aline Vieira. "EFEITO DO GRUPO GENÉTICO E PESO DE ABATE NAS CARACTERÍSTICAS DA CARCAÇA E QUALIDADE DA CARNE DE CORDEIROS CONFINADOS." Universidade Federal de Goiás, 2008. http://repositorio.bc.ufg.br/tede/handle/tde/1127.

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Made available in DSpace on 2014-07-29T15:13:43Z (GMT). No. of bitstreams: 1 alineteseca.pdf: 944325 bytes, checksum: 5f0b947649cbf727f1cd020b11cdb011 (MD5) Previous issue date: 2008-12-15 Sheep rearing is becoming an important economic activity, where it is necessary to establish the ideal slaughter weight per genetic group and sex to acheive standardized carcasses which meet customer needs in terms of product quality.This experiment evaluated the effect of genetic group and slaughter weight on carcass traits and meat quality in lambs. Twenty four Santa Ines (SI), 24 ½ Ile de France x ½ Santa Inês (ILE x SI) and 8 ½ Texel x ½ Santa Inês (TE x SI), slaughtered at different weights (30, 35, 40 and 45 kg ) were used.Eye rib area and fat thickness were measured in vivo and on the carcass. After a 16 hour food and water fast the animals were slaughtered conventionally and the carcasses placed in a cold chamber at 4ºC/24h. pH was measured at slaughter and after 24h as were subjective measurements on the Longissimus dorsi. A section of the rib region from the 11th to 13th ribs of the left side of the carcass was used for tissue and fractional composition, physic-chemical parameters and fatty acid composition. The experiment was in a 3 x 2 x 4 factorial design. For physic-chemical and fatty acids a 3 x 4 factorial and analysed using CORR (Correlation), REG (Regression) and Duncan (5%) means test in SAS ®. Genetic group did not influence (P>0.05) means for rib eye area or fat thickness measured by ultrasound or paquimeter. These measurements increased with slaughter weight. Tissue composition was influenced by genetic group and slaughter weight (P<0.05). The Texel x Santa Inês had most muscle (63.75 g), fat (53.75 g), bone (29.37 g) and edible portion (78.75%) at 35 and 45 kg . Slaughter weight centesimal composition, with an increase in total lipids as weight increased. No significant differences were found for final pH between genetic groups and slaughter weights. Genetic group did not influence colour (3.32), shear force (3.57 kgf) or loss in cooking (24.05%) of the Longissimus dorsi, but slaughter weight affected these, causing stronger colour, tougher meat and greater loss in cooking as slaughter weight increased. Significant differences were found in the sensorial traits of the meat with different genetic groups and slaughter weights. The fatty acids found included oleic (43%); palmitic (22%) and estearico (18%). Higher quantities of desirable fatty acids were found in the Texel x Santa Inês (66.78%) group. Slaughter weight caused a significant difference (P<0.05) in the fatty acid profile of saturated and polyunsaturated fats. A criação de ovinos surge como atividade de importância econômica, na qual busca-se estabelecer o peso ideal para abate por grupo genético e sexo, proporcionando carcaças padronizadas que satisfaçam as perspectivas dos consumidores em termos de qualidade do produto. Objetivou-se com este experimento avaliar os grupos genéticos e peso de abate nas características da carcaça e qualidade da carne de cordeiros. Foram utilizados 24 cordeiros Santa Inês (SI), 24 cordeiros mestiços ½ Ile de France x ½ Santa Inês (ILE x SI) e 8 cordeiros mestiços ½ Texel x ½ Santa Inês (TE x SI), abatidos em diferentes pesos (30, 35, 40 e 45 kg). As análises de área de olho de lombo e espessura de gordura foram realizadas in vivo e na carcaça dos animais. Após jejum e dieta hídrica de 16 h, os animais foram submetidos ao abate convencional e as carcaças permaneceram em câmara fria a 4ºC/24h. Durante esse período foi realizada a leitura de pH inicial e final (24 h) e avaliações subjetivas no músculo Longissimus dorsi. Posteriormente foram retiradas as frações correspondentes à região da 11ª a 13ª costelas da carcaça esquerda para as análises de composição tecidual e centesimal, avaliação dos parâmetros físico-químicos e composição de ácidos graxos. O delineamento utilizado foi inteiramente casualizado em esquema de fatorial 3 (grupo genético) x 2 (sexo) x 4 (peso de abate). Para as análises físico-químicas e perfil de ácidos graxos foi utilizado fatorial 3 x 4 com aplicação de procedimentos CORR (Correlação), REG (Regressão) e teste de médias (Duncan 5%) do programa estatístico SAS. Os grupos genéticos não influenciaram (P>0,05) os valores médios da área de olho de lombo e espessura de gordura pelo ultra-som e paquímetro. Observou-se maior a área de olho de lombo e espessura de gordura na 12a costela com o aumento dos pesos ao abate. A composição tecidual foi influenciada pelos grupos genéticos e peso ao abate (P<0,05). Os animais Texel x Santa Inês apresentaram maior quantidade de músculo (63,75 g), gordura (53,75 g), osso (29,37 g) e porção comestível (78,75%) aos 35 e 45 kg. Houve efeito dos pesos de abate para a composição centesimal, apresentando aumento do teor de lipídeos à medida que os pesos eram elevados. Não houve diferença para pH final entre os grupos genéticos e pesos ao abate avaliados. Os grupos genéticos não influenciaram a cor (3,32), força de cisalhamento (3,57 kgf) e perda por cozimento (24,05%) do músculo Longissimus dorsi, no entanto, houve diferença significativa para os grupos de peso ao abate, atribuindo-se a coloração mais acentuada, carne menos macia e maior perda de líquido por cozimento com a elevação do peso ao abate. Foram detectadas diferenças nos atributos sensoriais avaliados nas carnes de cordeiros de diferentes genótipos e pesos ao abate. Os ácidos graxos encontrados em maior concentração foram o oléico (43%); palmítico (22%); esteárico (18%). Verificou-se maiores quantidades de ácidos graxos desejáveis em animais Texel x Santa Inês (66,78%). O peso de abate dos cordeiros determinou diferença significativa (P<0,05) no perfil dos ácidos graxos saturados e poliinsaturados.

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Andrade, Patrícia Bueno. "Avaliação físico-química de meias-carcaças bovinas resfriadas e de cortes dessossados sob emprego do filme stretch." Universidade Federal de Goiás, 2014. http://repositorio.bc.ufg.br/tede/handle/tede/4308.

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Submitted by Cássia Santos (cassia.bcufg@gmail.com) on 2015-03-17T10:56:03Z No. of bitstreams: 2 Dissertação - Patrícia Bueno Andrade - 2014.pdf: 1475062 bytes, checksum: 4e562bddc5f531befda3dd752b69d44f (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2015-03-20T13:56:48Z (GMT) No. of bitstreams: 2 Dissertação - Patrícia Bueno Andrade - 2014.pdf: 1475062 bytes, checksum: 4e562bddc5f531befda3dd752b69d44f (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Made available in DSpace on 2015-03-20T13:56:48Z (GMT). No. of bitstreams: 2 Dissertação - Patrícia Bueno Andrade - 2014.pdf: 1475062 bytes, checksum: 4e562bddc5f531befda3dd752b69d44f (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2014-09-30 Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq In the carcass cooling process, some important physical and chemical characteristics, such as weight loss, can be affected by the cooling method and speed. The weight loss during cooling is considered natural and is usually caused by superficial dehydration and exudation of carcasses, and has major economic consequences for meat industry, which tends to seek methods to improve yields and profits of slaughter. Accordingly, one proposed method is the use of stretch polyethylene film, which involves the half-carcass and reduces evaporation and water loss to the environment. Considering these aspects, this study evaluated the physicochemical quality of beef half-carcasses after healthy maturation of boneless meat cuts using stretch film. The experiment consisted of two stages with a total of 482 animals. The first stage comprised two slaughters of 241 carcasses in each one. Before healthy maturation, the carcasses were sectioned in half-carcasses and then divided into two groups; coated (right half-carcass) and uncoated (control - left halfcarcass). Each group was placed in a different chamber. All half-carcasses were weighed before and after maturation to calculate weight loss by evaporation. Half-carcasses of the coated group were previously involved in the film. We randomly selected four half-carcasses from one chamber, and the corresponding half-carcasses from the other chamber, where temperature, pH and color measurements were carried out. The half-carcasses remained within the chamber for a minimum period of 24 hours. In the second stage, we randomly withdrew 25 pieces of two kinds of cuts (eye round and knucle) from the half-carcasses of the two slaughters, totaling 200 cuts, and stored them for periods of seven, 15, 30, 45 and 60 days. In each period, five samples of each type of cut (eye round and knucle) and each group (control and stretch), 20 samples per day, from the two slaughters, totaling 200 samples. Analyses of weight loss by exudation, temperature, pH, water holding capacity (WHC) and humidity were carried out at the Laboratory of Physical-Chemistry of the Food Research Centre, School of Veterinary and Animal Science (UFG). Significant reduction (p <0.05) was observed in the weight loss of half-carcasses using the film during the first 24 hours of cooling, where losses have reduced from 2.29% to 1.27%. Significant effect of the plastic film was observed on the temperature of the half-carcasses (p<0.05), being the coated ones 1.18ºC warmer than the uncoated ones. The plastic did not affect the pH decrease (p>0.05), but it affected the color (p<0.05). Effect of the film (p<0.05) was verified on exudation losses, temperature, humidity and WHC of the stocked meat cuts. From the results, we concluded that the stretch film is an efficient technique that reduces weight losses during carcasses cooling; however, it hinders the reduction of temperature inside the carcasses, thus promoting microbial growth and physical and chemical changes in the meat. Storing the meat cuts from the coated half-carcasses, exudation losses, temperature, water holding capacity and moisture were affected by use of the technique. No processo de resfriamento de uma carcaça, algumas características físico-químicas importantes como a perda de peso podem ser influenciadas pelo método e pela velocidade de resfriamento. Esta perda de peso durante o resfriamento é considerada natural e normalmente é ocasionada pela desidratação superficial e exsudação das carcaças, e traz grandes consequências econômicas às indústrias frigoríficas, que tendem a procurar métodos para melhorar os rendimentos e o lucro da operação de abate. Nesse sentido, um método proposto é a utilização de filme de polietileno stretch que envolve a meia-carcaça e reduz a evaporação e perda de água para o ambiente. Mediante a estes aspectos, o estudo avaliou a qualidade físico-química de meias-carcaças bovinas após a maturação sanitária e de cortes cárneos desossados sob emprego do filme stretch. Foram realizadas duas etapas com um total de 482 animais. Na primeira etapa sendo dois abates, em cada um utilizou-se 241 carcaças e antecedendo a maturação sanitária, após secção das carcaças em meiascarcaças foram divididas em dois grupos; com revestimento (meia-carcaça direita) e sem revestimento (controle – meia carcaça-esquerda), cada grupo direcionado a uma câmara diferente. Todas as meias-carcaças foram pesadas antes e pós-maturação sanitária para cálculo da perda de peso por evaporação. As meias-carcaças do grupo com revestimento foram previamente envolvidas pelo filme. Aleatoriamente, selecionou-se 4 meias-carcaças de uma câmara, e a meia-carcaça correspondente na outra câmara, nestas foram realizadas as medições de temperatura, pH e cor. As meias-carcaças permaneceram dentro da câmara por um período mínimo de 24 horas. Na segunda etapa a partir das meias-carcaças dos dois abates foram retiradas aleatoriamente 25 peças de 2 tipos de cortes lagarto e patinho, de cada grupo, nos dois abates, totalizando 200 cortes, e foram estocados por períodos de 7, 15, 30, 45, 60 dias. Em cada período foram retiradas 5 amostras de cada tipo de corte (lagarto e patinho) e de cada grupo (controle e com revestimento), sendo 20 amostras por data, nos dois abates, totalizando 200 amostras. As análises de perda de peso por exsudação, temperatura, pH, capacidade de retenção de água (CRA) e umidade foram realizadas no Laboratório de Físico-Química do Centro de Pesquisa em Alimentos da Escola de Veterinária e Zootecnia (EVZ/UFG). Foi verificada significativa redução (p<0,05) nas perdas de peso das meias-carcaças com o uso do filme durante as primeiras 24 horas de resfriamento, sendo que as perdas reduziram de 2,29% para 1,27%. Houve influência significativa do filme plástico na temperatura das meias-carcaças (p<0,05), sendo as revestidas 1,18ºC mais quentes que as sem revestimento. O plástico não influiu sobre a redução do pH (p>0,05), e houve influência do filme sobre a cor (p<0,05). Houve efeito do filme (p<0,05) nas perdas por exsudação, na temperatura, na CRA e na umidade dos cortes cárneos estocados. A partir dos resultados, conclui-se que o revestimento stretch é uma eficiente técnica que reduz as perdas de peso durante o resfriamento de carcaças bovinas, porém, dificulta a redução de temperatura no interior das carcaças, o que favorecerá o crescimento microbiológico e modificações físico-químicas na carne. Ao estocar cortes cárneos provenientes das meias-carcaças com revestimento, as perdas por exsudação, a temperatura, a capacidade de retenção de água e a umidade são afetadas pelo uso da técnica.

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Le?o, Adriano de Castro. "Estudo comportamental, hormonal e histopatol?gico de animais com perda de peso progressina (SEP) e da vari?vel peso associada a uma nova classifica??o ontogen?tica em Callithrix jacchus." Universidade Federal do Rio Grande do Norte, 2007. http://repositorio.ufrn.br:8080/jspui/handle/123456789/17193.

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Made available in DSpace on 2014-12-17T15:36:30Z (GMT). No. of bitstreams: 1 AdrianoCL.pdf: 471335 bytes, checksum: 56ca8b5db29eb13c8ee17c7dee626744 (MD5) Previous issue date: 2007-09-24 The use of non-human primates in scientific research has contributed significantly to the biomedical area and, in the case of Callithrix jacchus, has provided important evidence on physiological mechanisms that help explain its biology, making the species a valuable experimental model in different pathologies. However, raising non-human primates in captivity for long periods of time is accompanied by behavioral disorders and chronic diseases, as well as progressive weight loss in most of the animals. The Primatology Center of the Universidade Federal do Rio Grande do Norte (UFRN) has housed a colony of C. jacchus for nearly 30 years and during this period these animals have been weighed systematically to detect possible alterations in their clinical conditions. This procedure has generated a volume of data on the weight of animals at different age ranges. These data are of great importance in the study of this variable from different perspectives. Accordingly, this paper presents three studies using weight data collected over 15 years (1985-2000) as a way of verifying the health status and development of the animals. The first study produced the first article, which describes the histopathological findings of animals with probable diagnosis of permanent wasting marmoset syndrome (WMS). All the animals were carriers of trematode parasites (Platynosomum spp) and had obstruction in the hepatobiliary system; it is suggested that this agent is one of the etiological factors of the syndrome. In the second article, the analysis focused on comparing environmental profile and cortisol levels between the animals with normal weight curve evolution and those with WMS. We observed a marked decrease in locomotion, increased use of lower cage extracts and hypocortisolemia. The latter is likely associated to an adaptation of the mechanisms that make up the hypothalamus-hypophysis-adrenal axis, as observed in other mammals under conditions of chronic malnutrition. Finally, in the third study, the animals with weight alterations were excluded from the sample and, using computational tools (K-means and SOM) in a non-supervised way, we suggest found new ontogenetic development classes for C. jacchus. These were redimensioned from five to eight classes: infant I, infant II, infant III, juvenile I, juvenile II, sub-adult, young adult and elderly adult, in order to provide a more suitable classification for more detailed studies that require better control over the animal development O uso de primatas n?o humanos na pesquisa cient?fica trouxe grandes contribui??es ? ?rea biom?dica e, no caso de Callithrix jacchus, evid?ncias importantes sobre mecanismos fisiol?gicos para compreens?o de sua biologia bem como para a sua proposi??o como modelo experimental em diferentes patologias. Entretanto, a cria??o de primatas n?o humanos em cativeiro por longos per?odos de tempo ? acompanhada de transtornos comportamentais e doen?as cr?nicas, a maioria delas apresentando como sinal prim?rio a perda progressiva de peso. O N?cleo de Primatologia da Universidade Federal do Rio Grande do Norte (UFRN) possui uma col?nia de cria??o de C. jacchus h? cerca de 30 anos e durante este per?odo seus animais foram pesados sistematicamente como forma de detectar poss?veis altera??es nas suas condi??es cl?nicas. Este procedimento gerou uma massa de dados sobre o peso dos animais em diferentes faixas et?rias de grande relev?ncia para o estudo desta vari?vel em diferentes perspectivas. Neste contexto, o presente trabalho apresenta tr?s estudos usando os dados da vari?vel peso coletados durante 15 anos (1985-2000) como forma de aferir o estado de sa?de e do desenvolvimento dos animais. O primeiro estudo gerou o primeiro artigo, o qual descreve os achados histopatol?gicos de animais com diagn?stico prov?vel da S?ndrome de Emagrecimento Progressivo (SEP), tendo sido encontrado que todos eles eram portadores de um tremat?deo (Platynosomum spp) associado a um quadro de obstru??o no sistema hepatobiliar, para o qual se prop?s este agente como um dos fatores etiol?gicos da s?ndrome. No segundo artigo a an?lise foi direcionada ? compara??o do perfil comportamental e do n?veis de cortisol entre animais com a evolu??o da curva de peso dentro dos par?metros de normalidade e ?queles com SEP. Ficou evidenciada a diminui??o na locomo??o, uso aumentado dos extratos inferiores da gaiola e hipocortisolemia, esta ?ltima provavelmente associada a uma adapta??o dos mecanismos que comp?em o eixo funcional hipot?lamo-hip?fise-adrenal,, como observado para outros mam?feros sob situa??es de desnutri??o cr?nica. Finalmente, no terceiro estudo, os animais com altera??es de peso foram exclu?dos da amostra e, com o emprego de ferramentas computacionais (K-m?dias e SOM Self-Organizing Maps) de maneira n?o supervisionada, e foram evidenciadas novas classes no desenvolvimento ontogen?tico de C. jacchus. Assim sugerimos ser redimensionada de cinco para oito novas classes: infantil I, infantil II, infantil III, juvenil I, juvenil II, sub-adulto, adulto jovem e adulto idoso, fornecendo uma classifica??o mais apropriada para estudos mais detalhados que requeiram maior controle do desenvolvimento do animal

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Pérez, Simbor Sofía. "In-body to On-body Experimental UWB Channel Characterization for the Human Gastrointestinal Area." Doctoral thesis, Universitat Politècnica de València, 2019. http://hdl.handle.net/10251/133034.

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Abstract:

[ES] La población mundial en países desarrollados está envejeciendo y con ello existe un aumento de enfermedades en gran medida causadas por la edad. Las nuevas tecnologías médicas pueden ayudar a detectar, diagnosticar y tratar estas enfermedades y con ello ahorrar dinero, tiempo y recursos de los sistemas sanitarios. Las tecnologías inalámbricas implantables han abierto un nuevo panorama para la próxima generación de tecnologías médicas. Frecuencias como la Ultra Wide-Band (UWB) de 3.1 a 10.6 GHz están siendo consideradas para la nueva generación de dispositivos inalámbricos para dentro del cuerpo humano. Las características como el reducido tamaño de las antenas, la baja potencia de transmisión y la alta velocidad de datos son las más buscadas en este tipo de dispositivos. El problema surge porque el cuerpo humano depende de la frecuencia de modo que a mayores frecuencias, mayores son las pérdidas por propagación. Conociendo el canal de transmisión se puede solventar el problema de las altas pérdidas. Esta tesis tiene como objetivo caracterizar el canal de radio frecuencia (RF) para la nueva generación de dispositivos médicos implantables. Para caracterizar el canal se han empleado tres diferentes metodologías: simulaciones numéricas, medidas en phantom y experimentos en animales vivos. Las medidas en phantom fueron realizadas en un nuevo sistema de medidas expresamente disen¿ados para medidas de dentro a fuera del cuerpo humano en la banda de frecuencias UWB. Además, se utilizó un novedoso recipiente con dos capas de phantom imitando la zona gastrointestinal del cuerpo. Estos phantoms fueron creados para este tipo de medidas y son extremadamente precisos a las frecuencias UWB. Para los experimentos en animales se utilizaron cerdos y se intentó reproducir en ellos las medidas previamente realizadas en phantom. Las simulaciones software se realizaron con la intención de replicar ambas metodologías. Una vez realizados los experimentos se realizó un extensivo estudio del canal en dominio frecuencial y temporal. Mas en detalle, se compararon las antenas usadas en la recepción y transmisión, el efecto de la grasa en el canal, la formas del recipiente contenedor de phantom y las componentesmulticamino. Como resultado se ha propuesto un modelo de propagación del canal para la banda baja de las frecuencias UWB (3.1 -5.1 GHz) para la zona gastrointestinal del cuerpo humano. Este modelo de propagación ha sido validado utilizando las tres metodologías previamente descritas y comparada con otros estudios existentes en literatura. Finalmente, se midió el canal de propagación para una determinada aplicación a bajas frecuencias con señales UWB. También se realizaron medidas del canal de propagación en la zona cardíaca del cuerpo humano desde un punto de vista de seguridad de datos. Los resultados obtenidos en esta tesis confirman los beneficios que tendría la utilización de frecuencias UWB para las futuras generaciones de dispositivos médicos implantables. [CA] La població mundial a països desenvolupats està envellint-se i enfrontant-se a un augment d'infermetats principalment causades per la edat. Les noves tecnologies mèdiques poden ajudar a detectar, diagnosticar i tractar aquestes malalties, estalviant diners, temps i recursos sanitaris. Els dispositius implantables sense fils han generat un nou panorama per a les noves generacions de dispositius mèdics. Les freqüències com la banda de UWB estan sent considerades per a les futures tecnologies implantables. La reduïda grandària de les antenes, la baixa potència de transmissió i les altes velocitats de dades son característiques buscades per als dispositius implantables. Per contra, els éssers humans depenen de la freqüència en el sentit que a majors freqüències, majors les pèrdues per propagació quan el senyal travessa el cos humà d'interior a exterior. Per solventar aquestes pèrdues el canal de propagació s'ha d'entendre i conèixer de la millor manera possible. Aquesta tesi doctoral te com a objectiu caracteritzar el canal de radio freqüència (RF) per a la nova generació de dispositius mèdics implantables. S'han emprat tres metodologies diferents per a realitzar aquesta caracterització: simulacions software, mesures amb fantomes i experiments amb animals vius. Els experiments amb fantomes es van realitzar a un sistema de mesures dissenyat expressament per a les transmissions de dins a fora del cos humà a les freqüències UWB. També es van utilitzar un contenidor per als fantomes de dues capes, imitant l'area gastrointestinal dels humans. Per als experiments a animals es van emprar porcs, replicant els experiments al laboratori en fantomes de la forma més semblant possible. Les simulacions software foren dissenyades per a imitar les experiments amb fantomes i animals. Després dels experiments el canal de propagació es va investigar exhaustivament des del domini freqüèncial i temporal. S'ha observat com les antenes en transmissió i recepció afecten al senyal, la influència de la grassa, la forma del contenidor de fantoma i les possibles contribucions multicamí. Finalment es proposa un nou model de propagació per a les baixes freqüències UWB (3.1 a 5.1 GHz) per a la zona GI del cos humà. El model es va validar utilitzant les tres metodologies abans esmentades i també foren comparades amb model ja existents a la literature. Finalment des d'un punt de vista aplicat, el canal es va avaluar per al senyal UWB a baixes freqüències (60 MHz). A més a més, per a la nova generació de marcapassos sense fil es va investigar el canal des d'un punt de vista de seguretat de dades. Els resultats obtinguts a aquesta tesi confirmen els avantatges d'emprar la banda de freqüències UWB per a la nova generació de dispositius médics implantables. [EN] The current global population in developed countries is becoming older and facing an increase in diseases mainly caused by age. New medical technologies can help to detect, diagnose and treat illness, saving money, time, and resources of physicians. Wireless in-body devices opened a new scenario for the next generation of medical devices. Frequencies like the Ultra Wide-band (UWB) frequency band (3.1 - 10.6 GHz) are being considered for the next generation of in-body wireless devices. The small size of the antennas, the low power transmission, and the higher data rate are desirable characteristics for in-body devices. However, the human body is frequency ependent, which means higher losses of the radio frequency (RF) signal from in- to out-side the body as the frequency increases. To overcome this, the propagation channel has to be understood and known as much possible to process the signal accordingly. This dissertation aims to characterize the (RF) channel for the future of in-body medical devices. Three different methodologies have been used to characterize the channel: numerical simulations, phantom measurements, and living animals experiments. The phantom measurements were performed in a novel testbed designed for the purpose of in-body measurements at the UWB frequency band. Moreover, multi-layer high accurate phantoms mimicking the gastrointesintal (GI) area were employed. The animal experiments were conducted in living pigs, replicating in the fairest way as possible the phantom measurement campaigns. Lastly, the software simulations were designed to replicate the experimental measurements. An in-depth and detail analysis of the channel was performed in both, frequency and time domain. Concretely, the performance of the receiving and transmitting antennas, the effect of the fat, the shape of the phantom container, and the multipath components were evaluated. Finally, a novel path loss model was obtained for the low UWB frequency band (3.1 - 5.1 GHz) at GI scenarios. The model was validated using the three methodologies and compared with previous models in literature. Finally, from a practical case point of view, the channel was also evaluated for UWB signals at lower frequencies (60 MHz) for the GI area. In addition, for the next generation of leadless pacemakers the security link between the heart and an external device was also evaluated. The results obtained in this dissertation reaffirm the benefits of using the UWB frequency band for the next generation of wireless in-body medical devices. Pérez Simbor, S. (2019). In-body to On-body Experimental UWB Channel Characterization for the Human Gastrointestinal Area [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/133034 TESIS

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