• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 10146
  • 4938
  • 806
  • 552
  • 536
  • 528
  • 528
  • 528
  • 528
  • 528
  • 329
  • 245
  • 164
  • 157
  • 135
  • Tagged with
  • 21811
  • 2722
  • 2284
  • 1983
  • 1783
  • 1696
  • 1523
  • 1436
  • 1314
  • 1140
  • 1126
  • 1102
  • 1026
  • 1011
  • 1006
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Thinking outside the cage : sacrifice, equality and the plight of the animal

De Villiers, Jan-Harm 27 May 2013 (has links)
In this dissertation I illustrate the existence of anthropocentric social and legal configurations that are maintained through the embodiment of a belief system in which animals occupy a space as sacrificial beings, and philosophically examine and call into question the way in which we relate to animals within these schemata of domination. These sacrificial structures or arrangements contain animals in an identity which marks them as Other and I subsequently call for a problematisation and destabilisation of these structures. I employ a critical approach that seeks to move beyond the traditional rights-based approach that has come to dominate animal liberation discourse. Such an approach emphasises the significance of deconstruction for animal ethics and highlights the way in which the animal is subjected to marginalisation within anthropocentric schemata of domination. From this perspective, I argue that we need a deconstruction and ensuing displacement of the human (subject) as phallogocentric structure and that we need to embrace a mode of being that facilitates the development of an ethical relation to the animal Other. To this end, I advance veganism as a form of deconstruction and ethical way of being that allows us to criticise and resist repression of the animal Other. I also contemplate animal subjugation as a relation to the law and examine the ideological underpinnings of animal welfare theory and animal rights theory, the two most prominent theories aimed at transforming the human-animal relation. I proceed to critically engage with the philosophical presuppositions of animal rights theory as a possible foundation for animal liberation by addressing, like others have done before me, the historical and theoretical gaps of rights theory. I argue that animal rights theory invokes dichotomies and rigid identities that replicate and perpetuate anthropocentric relations of subordination by (paradoxically) confirming a certain interpretation of the human subject that lies at the very core of animal subjugation. I ultimately argue that such an approach must be rejected if we are to hold open the possibility of recalibrating the animal's status as sacrificial being. / Dissertation (LLM)--University of Pretoria, 2012. / Jurisprudence / unrestricted
12

Fertility Associated Antigen (FAA): Economics of Testing

Skopp, Stacy January 2011 (has links)
Proteins in bull semen have been found that increase fertility, including the fertility-associated antigen (FAA). The uses of FAA-positive bulls have been found in previous studies to increase conception rates at least 16%. Increased fertility rates by FAA-positive bulls increased the number of pregnant cows early in the breeding seasonUsing historical data to compute an equation that can demonstrate buyers and producers in the Southwestern United States the benefits of using and testing for FAA-positive bulls over time. The cost for addition of a cassette to the BSE testing will be offset by an increase in conception rate, birthing rate, and increase calf weaning weightsThis study focuses on the Southwestern United States, but eventually the information may be used nationwide. Fertility-associated antigen is a new science that is being studied to help the cattle industry increase production and profitability.
13

Genetic aspects of pigment production in the guinea pig

Alsop, Annette January 1940 (has links)
No description available.
14

Filogeografia do gênero Rhizoprionodon (Elasmobranchii, Carcharhinformes) no Atlântico Ocidental utilizando marcadores moleculares do DNA mitocondrial /

Mendonça, Fernando Fernandes. January 2010 (has links)
Resumo: Os tubarões representam atualmente um importante recurso para a pesca mundial. No entanto, a falta de informações básicas tais como características populacionais, definições taxonômicas precisas e avaliações dos volumes capturados têm favorecido a contínua e intensiva exploração de espécies e populações que já podem estar apresentando declínios em níveis críticos para a manuntenção da sustentabilidade. Pertencente à família Carcharhinidae, o gênero Rhizoprionodon é constituído por sete espécies de tubarões de pequeno porte distribuídas em praticamente todos os mares e devido seus hábitos associados às regiões costeiras, frequentemente representam uma grande parcela dos volumes desembarcados. Destas espécies, três apresentam-se distribuídas no Atlântico Ocidental (R. terraenovae, R. porosus e R. lalandii) com ocorrências desde o Norte dos EUA até a América do Sul, onde a pesca tem sido intensa, principalmente no Brasil. No presente estudo, utilizando marcadores moleculares do DNA mitocondrial, foram analisadas as estruturas populacionais das espécies R. porosus e R. lalandii, desde o Mar do Caribe até a região sul do Brasil, foi buscada a distinção espécie-específica entre R. terraenovae e R. porosus e foram desenvolvidos protocolos de identificação forense para espécies de tubarões amplamente explorados pela pesca na costa brasileira. Na análise utilizando sequencias da região controladora do mtDNA de amostras de R. porosus foram encontrados 53 halótipos com forte estruturação populacional (FST=0.271, P<0,0001), caracterizando a existência de duas populações distintas, separadas pela Corrente Marítima do Equador. Entre os tubarões da espécie R. lalandii foram encontrados 30 haplótipos também com forte estruturação (FST=0.254, P<0,0001) entre as populações do Caribe e as demais populações da costa brasileira. Provavelmente... (Resumo completo, clicar acesso eletrônico abaixo) / Not available / Orientador: Fausto Foresti / Coorientador: Otto Bismarck Fazzano Gadig / Banca: Claudio de Oliveira / Banca: Iracilda Sampaio / Banca: Rui Coelho / Banca: Patricia Charvet / Doutor
15

Efeito de dois alimentos comerciais secos no consumo energético, peso vivo e peso metabólico, escore corporal, escore e peso fecal de cães adultos em manutenção e atividade / Effect of two dry comercial feeds on energy consumption, body and metabolic weights, corporal score, faecal weight and score of adult dogs in maintenance and agility

Veronesi, Carla 24 October 2003 (has links)
Com o objetivo de avaliar a ingestão calórica e características fecais de cães adultos em manutenção e em atividade, dois grupos de animais foram utilizados, sendo o primeiro grupo composto por 4 cães ativos da raça Border Collie e o segundo composto por 14 cães de raças variadas. Foram fornecidos dois tipos de alimentos comerciais secos, um deles considerado superpremium (S) e o outro considerado popular (P). O experimento teve duração de 40 dias, e os resultados mostraram que o alimento S produz menor peso fecal e consistência mais firme, enquanto que o alimento P obteve peso fecal maior e consistência menos firme. Além disso, os animais ativos necessitam de maior demanda energética para o seu conforto metabólico do que os animais inativos, apesar de não terem perdido peso vivo e o escore corporal não ter sido modificado. / The aim of this study was to evaluate the energy comsumption and faecal characteristics of the adult dogs in maintenance and agility, two groups of animals have been used, first four active dogs Border Collie breed and the second 14 dogs of different breeds. Two tips of commercial dry feeds were offered, one of them superpremium (S) and the second usual (P). The experiment were carried out in 40 days, and the results should that feed S produced lower faecal weight and more consistent. Forthermore, the agility animals needed higher energetic demand for it metabolic comfort then inactive animals, otherwise had not lost body weight and score had not modified.
16

Development of a Fibroblast Growth Factor 21 Assay

Tamassia, Gabriela V. 09 March 2019 (has links)
<p> Obesity and diabetes play a major role in many diseases prevalent in our current society. Fibroblast Growth Factor 21 (FGF21) is a recently discovered hormone that has potential for therapeutic treatment of obesity and diabetes. It acts as a hormone in times of metabolic stress and is shown to stimulate hepatic fatty acid oxidation, ketogenesis, induce weight loss, allow for sustained decrease in plasma glucose and triglycrides, and decrease the growth hormone response. Obese or diabetic individuals often have higher than normal amounts of circulating FGF21; consequently, they may be considered FGF21 resistant. It is then advantageous to have an assay to measure FGF21 that will allow us to study FGF21 further. It is also important to study FGF21 in various livestock species for potential biomarkers, or as indicators of carcass quality that could prove to advance further research. We have developed a working FGF21 assay using an amplified luminescent proximity homogeneous assay (AlphaLISA). It is a homogeneous, no-wash immunoassay with high sensitivity and wide dynamic range. It is a bead based technology that brings two antibodies near each other allowing for an unstable singlet oxygen to trigger a downstream cascade of chemical events leading to a sharp intense chemiluminescent emission that can be read on an EnVision machine. The assay was set up using a &lsquo;sandwich&rsquo; design with guinea pig or rabbit anti-bovine FGF21 antibodies attached to the acceptor beads and biotinylated rabbit anti-bovine FGF21 antibodies attached to a streptavidin coated donor bead. The assay has a working range from 0.2- 200 ng/ml. Standard curves in serum from bovine, porcine, rabbit, rat, ewe, fetal bovine has been conducted and assay conditions were optimized for each. Manipulations of the sera were necessary in order to get functional curves. These included diluting it 2 fold or more, depending on the species, and increasing incubation temperatures. The assay can function using both serum and plasma. </p><p>
17

The impact of digestive enzymes in the ruminant animal

Keomanivong, Faithe Elizabeth 12 January 2017 (has links)
<p> Understanding the enzymatic activity in ruminant digestive systems is essential for securing adequate growth, reproduction and overall metabolism. In order to evaluate the impact of various nutritional sources and dietary strategies on enzymatic activity, five experiments were designed. Experiment 1 examined the influence of nutrient restriction and melatonin supplementation on maternal and fetal pancreatic development. Experiment 2 explored various phases of the reproductive cycle and the impact of intravenous arginine infusion amid differing levels of feed intake. Experiment 3 determined the effectiveness of realimentation during advancing stages of gestation. Experiments 4 and 5 examined the impact of variable rations on ruminal pH, NH3, VFA, total gas and methane concentration and enzymatic activity in steers consuming rations of fine- vs coarse-rolled corn and 20% vs 40% DDGS (Experiment 4) and corn vs barley based diets with low- vs moderate-oil DDGS (Experiment 5). Overall, nutrient restriction caused reduced BW, pancreatic mass and pancreatic enzyme activity in mature animals. In Experiment 1, the addition of dietary melatonin diminished the impact of nutrient restriction on maternal pancreatic mass and &alpha;-amylase activity while reducing the secretion of insulin and size of insulin-containing cell clusters. Fetal pancreatic enzymes were unaffected by treatment, however, pancreatic morphology exhibited greater insulin-containing cell cluster size in fetuses from adequately fed dams. In Experiment 2, arginine infusion did not alter pancreatic exocrine or endocrine function during the various luteal stage phases. In Experiment 3, realimentation during different stages of gestation decreased the impact of reduced feed intake and, in some cases, allowed for compensatory gain of the exocrine pancreas. The maternal and fetal endocrine pancreas was unaffected. Mature animals had greater changes in pancreatic exocrine secretions whereas fetuses differed mainly in endocrine function as a result of improper nutritional status. Comparison of pancreatic tissue revealed a greater quantity, and larger size, of insulin-containing cell clusters in fetuses which appear to separate as the animal matures. Differences in rumen enzymatic activity was found in Experiments 4 and 5, however, despite changes in lag time of gas production or ruminal degradation rates, the concentration of greenhouse gases (CH<sub>4</sub> or CO<sub>2</sub>) produced were unaffected. </p>
18

Reduce Reuse Re-rumen| Repurposing Ruminal Waste for Sustainable Livestock Production

Garcia, Taylor Jacob 28 March 2019 (has links)
<p> Animals with multi-compartmented stomachs, also known as ruminants, are adapted to digest cellulosic materials, which constitute the primary expense on ranches and dairies. Industrial byproducts can be repurposed for livestock diets to decrease these costs. Therefore, finding alternative feedstuffs may benefit the economics of livestock production. The goal of this project was to evaluate alternative uses of ruminal waste from commercial abattoirs. This project addressed two primary objectives. First, ruminal fiber as a potential dietary fiber source was evaluated. Second, the potential for preservation of ruminal fluid for later use was assessed. Results for the first objective indicated harvesting rumen waste from slaughterhouses could be beneficial for sustainable livestock production, while reducing the environmental threat posed by disposal of ruminal waste. Nutritional values of rumen waste in relation to other common livestock roughages sources commonly found in ruminant diets are numberical , such as coastal Bermuda grass hay (<i>Cynodon dactylon </i>) and alfalfa hay (<i>Medicago sativa</i>). Neutral detergent fiber (NDF), acid detergent fiber (ADF), acid detergent lignin (ADL) and crude protein (CP) values were 68.1%, 39.9%, 10.9% and 15%, respectively. Contribution to variance for NDF, ADF, ADL and CP were 97.2%, 97.9%, 95.4% and 19.1%, respectively. <i> In vitro</i> true digestibility (IVTD) and <i>in vitro</i> neutral detergent fiber digestibility (IVNDFD) were 46.2% and 21.6%, respectively. Results from the second objective showed lower degradation of feeds when frozen or lyophilized rumen fluid was used rather than fresh inoculum; however, differences in IVTD and IVNDFD suggest that, in the absence of fresh inocula, preserved rumen fluid may be a viable option. Implications from this study show rumen content could provide nutrients if fed to livestock and rumen microbes preserved (frozen or lyophilized) are still viable and able to degrade feedstuffs. Therefore, further research is needed to assess the consistency of using inoculum from slaughtered cattle and improve the preservation process.</p><p>
19

The existence and nature of hypothyroidism in reproductively inhibited prairie deermice (Peromyscus maniculatus bairdi) from laboratory populations

Pitman, John Mathews 01 January 1983 (has links)
No description available.
20

Evaluation of Antiviral Compounds Against Avian Influenza

Call, Evan W. 01 May 1991 (has links)
Tests in vitro for antiviral activity against avian influenza viruses, A/Turkey/Sanpete/85 (H6N8) and A/Turkey/Sanpete/86 (H10N9), isolated in Sanpete County, Utah, utilized known antiviral agents, amantadine•HCl (adamantanamine hydrochloride) and ribavirin (1-β-D ribofuranosyl-1,2,4-triazole-3-carboxamide). The testing involved evaluation of seven drug concentrations. Maximum tolerated dose, minimum inhibitory concentration and therapeutic indexes were determined for each drug used. Both drugs demonstrated reasonable antiviral activity. Then they were tested against the H10N9 strain in 10-day-old Broad White turkey poults. Large- and small- particle aerosol delivery methods utilized. Various parameters, including water and feed consumption, health score (based on visible signs), recoverable lung virus, lung hemagglutination titer, and visual lung scoring were considered for the quantification of viral infection and, thus, antiviral activity in birds. Recovery of viable virus from infected turkey poults proved sporadic. Visible signs were varied and mild, limiting the usefulness of health scores. The onset of illness was reflected in the decline in water consumption. Moderate antiviral activity was demonstrated with the use of ribavirin small-particle aerosol, but ribavirin fog was not effective. Amantadine product slight antiviral activity when used with both delivery systems. The potential efficacy of both drugs and application methods indicate further study of these control systems is warranted.

Page generated in 0.0526 seconds