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  • 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.
161

Coagulase-negative staphylococci in bovine sub-clinical mastitis /

Thorberg, Britt-Marie, January 2008 (has links) (PDF)
Licentiatavhandling (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2008. / Härtill 2 uppsatser. I boken felaktigt tryckår 2006.
162

Effects of culture methods and simulated microgravity conditions on development of bovine embryos produced in vitro

Jung, Song-Yi, January 2008 (has links)
Thesis (M.S.)--Mississippi State University. Department of Animal and Dairy Sciences. / Title from title screen. Includes bibliographical references.
163

Diagnostic and epidemiological studies of staphylococci in bovine mastitis /

Capurro, Aldo, January 2009 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2009. / Härtill 4 uppsatser.
164

Conteúdo celular do leite bubalino proveniente de quartos mamários sadios e portadores de mastite

Pardo, Renata Bonini [UNESP] 02 July 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:52Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-07-02Bitstream added on 2014-06-13T19:03:32Z : No. of bitstreams: 1 pardo_rb_dr_jabo.pdf: 1134204 bytes, checksum: f5af7219cd5d0c42c86945ad29a46afe (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Os exames de palpação, inspeção e teste da caneca de fundo escuro, bem como o California Mastitis Test (CMT) foram realizados em 735 quartos mamários de búfalas leiteiras pesquisa de alterações clínicas e subclínicas nos quartos e em suas respectivas secreções. Independentemente dos resultados encontrados, foram coletadas amostras de leite para análises microbiológicas e de contagem de células somáticas (CCS). O isolamento microbiológico foi realizado em ágar sangue de ovino 5% e em ágar MacConkey, com 72 horas de incubação em aerobiose a 37oC. Foram procedidas, a cada 24 horas, leitura e identificação dos isolamentos. A ocorrência de quadros de mastite clínica foi representada por um único caso (0,14%) entre os 735 quartos mamários analisados, ocorrendo na fase inicial da lactação e envolvendo microrganismos de origem ambiental (Morganella morganii, Enterobacter aerogenes). Foram considerados quadros de mastite subclínica aqueles com resultados positivos ao CMT acompanhados de exame microbiológico positivo. A freqüência observada de quadros de mastite subclínica entre os 734 quartos mamários estudados foi de 20,03%, dos quais isolou-se principalmente microrganismos contagiosos. Os resultados negativos ao CMT predominaram durante todo o estudo (69,07%), independente da fase de lactação ou estação do ano consideradas, tendo sido observados resultados positivos do exame microbiológico em 57,58% das amostras CMT negativas. Foi elevada a freqüência de microrganismos classificados como contagiosos entre as amostras de leite analisadas, independente da estação do ano e da fase de lactação, entre os quais prevaleceu o Corynebacterium spp. (47,67%), entre os 579 microrganismos pertencentes a 19 gêneros bacterianos crescidos em cultura pura ou em associação. Considerando-se a falta de homogeneidade entre as variâncias, as contagens de células... / A total of 735 mammary quarters from buffalo cows were submitted to inspection, palpation, strip cup test and California Mastitis Test (CMT) in order to diagnose clinical and subclinical mastitis. Independent of the observed results, milk samples were collected from each mammary quarter to microbiological exams and automatic somatic cell counts (SSC). Milk samples were inoculated in 5% ovine blood agar and MacConkey agar and incubated for 72 hours under 37oC and aerobic condition. Growth observations and identifications were performed every 24 hours. One (0,14%) out of 735 mammary quarters studied presented clinical mastitis. It occurred in first stage of lactation (0 to 60th day post calving) and environmental microorganisms were isolated (Morganella morganii, Enterobacter aerogenes). Mammary quarters presenting positive results to CMT and microbiological exams were considered as subclinical mastitis cases and these represented 20,03% among 734 studied samples. CMT negative results were the most frequent observed during the study (69,07%), independent of lactation stage or season of the year considered. Among these CMT negative milk samples, 57,58% were positive in microbiological exams. There was a high occurrence of contagious microorganisms among the 579 identified bacteria from 19 different genus, isolated in pure or in association. Corynebacterium spp. was the most prevalent (47,67%), in every lactation stage or season of the year. Considering the absence of a normal distribution, somatic cell counts were submitted to a logarithmic transformation, log2(CCS/100)+3, originating the transformed somatic cell count (TSCC). There were statistically significant differences between TCCS means from milk samples with positive (2,23) and negative (1,71) results to CMT. Such differences were also observed in milk... (Complete abstract click electronic access below)
165

Effect of late pregnancy management on behaviour, welfare and calf health in dairy cattle

Fujiwara, Mayumi January 2018 (has links)
Studies in various animal species have demonstrated that stress during pregnancy can have a detrimental effect on progeny health and development throughout its postnatal life. If this were to apply to dairy cows, minimising stress in pregnant cows could be of critical importance in ensuring offspring health and welfare. However, relationships between maternal health and welfare and offspring performance have not been well investigated in dairy cattle. Traditionally management strategies for cows in late pregnancy (i.e. in the dry period) have focused on maximising milk production whilst minimising impacts on postpartum health. This may include management practices that can have a negative impact on the health and welfare of cows in the dry period itself. This project aimed to identify potential sources of stress associated with management practices in late pregnant cows, and to investigate its effects on offspring health, behaviour and welfare. A survey was conducted to investigate typical dry cow and pre-weaned calf management practices on dairy farms in the United Kingdom (UK). Data from 148 commercial UK dairy farms provided valuable information on dry cow and pre-weaning calf management. Procedures that were commonly practised but potentially stressful for dry cows included the abrupt cessation of milking and frequent changes in diet and social environment. Two experimental studies were conducted to investigate the impact of alternative management practices in late pregnancy on progeny welfare. The first experiment investigated the behavioural, physiological and metabolic responses of dry cows to industry minimum standards (H: high stocking group) compared to a more extensive space allowance (L: low stocking density). The offspring of these cows were monitored until weaning to assess their responses to typical dairy farm procedures. The second experiment was conducted on calves born to heifers from an out-wintering project. Pregnant heifers were kept either indoor or outdoor grazing (on deferred grass or kale) throughout the winter period. The health, growth and behaviour of offspring were monitored for the first 14 days of life. Limited feed-face space resulted in altered feeding patterns and increased competition at the feed-face. There was no association between dry period stocking density and the physiology and metabolism of dry cows. Maternal treatment had no impact on pre-weaned calf birth weight, health, growth, passive immunity, neonatal vigour and the majority of behavioural outcomes. However, H calves made more frequent social contact with companions compared to L calves and showed higher behavioural reactivity to weaning. Maternal high stocking density treatment and previous disease incidence in calves reduced the behavioural reactions to disbudding and the expression of pain-related behaviours. Out-wintering of pregnant heifers on kale showed no negative impact on growth compared to the indoor group, whilst out-wintering on deferred grass resulted in the lowest growth rate. However, out-wintering on deferred grass may have enhanced offspring social motivation and learning ability. This study has demonstrated potential associations between maternal experience during pregnancy, and offspring growth and behaviour. The effect of maternal treatment on offspring behaviour may be more likely to emerge in challenging situations. Further research will be needed to understand the underlying mechanisms and to reach definite conclusions, which would have implications for improving the welfare of late pregnant cows and their offspring.
166

INVESTIGATING THE USE OF BLESSED THISTLE FOR AMELIORATION OF SYMPTOMS OF FESCUE TOXICITY IN BEEF COWS CONSUMING ENDOPHYTE-INFECTED TALL FESCUE SEED

Douglas, Jamie Marguerite 01 December 2015 (has links)
The present investigation was designed to investigate the use of blessed thistle (Cnicus benedictus) in amelioration of fescue toxicosis in beef cattle. Twenty-seven crossbred Angus cows were blocked by age and weight into groups of three. Each group (n=9) was then randomly assigned to one of three dietary treatments: endophyte-free (EF), endophyte-infected (EI), or endophyte-infected with addition of cut and stemmed blessed thistle (EIBT). Each group was also randomly assigned to one of three 29-day replicates. Parameters measured during this trial included: urinary ergot alkaloid concentration (ng ergot alkaloids/mg creatinine), body weight (kg), rectal temperature (°C), serum progesterone (ng/ml), and serum prolactin (ng/ml). No effect of treatment (P>0.05) was detected in any of these parameters. A treatment x time interaction (P<0.0001) was observed for progesterone concentrations, likely a result of estrous cyclicity of cows. Results of this study suggest that we were unsuccessful in inducing fescue toxicity in test subjects assigned to EI and EIBT treatments. Minimal dietary ergovaline (1.72 μg kg-1) and cool ambient temperatures (-6.7°C to 23.3°C) likely contributed to this inability. Data from this research do suggest, however, that C. benedictus can be successfully incorporated into cattle diets. Further research will need to be performed to fully elucidate what, if any, benefits blessed thistle can have in the treatment of fescue toxicity.
167

Determinacao de pesticidas piretroides em leite bovino por meio da cromotografia a gas acoplada a espectrometria de massas de armadilha ionica - GC/ITMS ('Ion Trap')

SASSINE, ANDRE 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:47:13Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:10:36Z (GMT). No. of bitstreams: 1 08283.pdf: 7331635 bytes, checksum: 1c104b9cb00b73030780daec5c1d0c70 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
168

Estudo proteômico do desenvolvimento folicular de vacas zebuinas não gestantes / Estudo proteômico do desenvolvimento folicular de vacas zebuinas não gestantes

Lourenço, Tarcísio Torre [UNESP] 30 March 2016 (has links)
Submitted by TARCISIO TORRE LOURENÇO null (tarcisiolourenco16@yahoo.com.br) on 2016-12-09T13:14:54Z No. of bitstreams: 1 Dissertação Tarcísio com a ficha.pdf: 10339060 bytes, checksum: 23f48d3539cc446a8efd713c0a0b082d (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-12-13T10:58:12Z (GMT) No. of bitstreams: 1 lourenco_tt_me_bot.pdf: 10339060 bytes, checksum: 23f48d3539cc446a8efd713c0a0b082d (MD5) / Made available in DSpace on 2016-12-13T10:58:12Z (GMT). No. of bitstreams: 1 lourenco_tt_me_bot.pdf: 10339060 bytes, checksum: 23f48d3539cc446a8efd713c0a0b082d (MD5) Previous issue date: 2016-03-30 / O ciclo estral da vaca é composto por 2-3 ondas de crescimento folicular, no qual vários folículos são recrutados e iniciam um novo crescimento. Durante o período denominado desvio folicular, um folículo se torna dominante e os outros entram em atresia. Este processo envolve um mecanismo ainda não completamente compreendido, incluindo proteínas específico, como já estabelecido pela expressão gênica. O objetivo do presente estudo foi caracterizar as proteínas do fluído folicular a fim de identificar macromoléculas relacionadas ao desenvolvimento dos folículos de vacas zebuínas nã-gestantes. Foram colhidos os ovários de 25 vacas mestiças não-gestantes em um abatedouro. A presença do corpo lúteo foi anotada para cada ovário. O líquido folicular foi colhido utilizando-se a imersão do ovário em meio líquido e ultrassonografia. De acordo com a mensuração do diâmetro folicular, foram formados 3grupos, folículos pequenos (≤6,5mm, n=25), médios (>6,5mm a ≤9mm, n=9) e grandes (>9,0mm, n=11). Após 2 centrifugações (600xg/10 minutos e 15.000xg/30 minutos, 4ºC) o sobrenadante foi separado e utilizado para determinação da concentração de proteína total (método de Bradford). A eletroforese foi conduzida sob condições desnaturantes e redutoras, em gel de separação de poliacrilamidaà 12%. A concentração de progesterona e estradiol do líquido folicular foi determinada a fim de identificar os folículos saudáveis. As proteínas diferenciais identificadas pela eletroforese foram submetidas à espectrometria de massas e a ontologia gênica foi investigada nos bancos de dados disponíveis. Foram encontradas 45 bandas proteicas em 45 amostras de líquido folicular. A média da concentração ± desvio padrão da progesterona foi de 129,91 ± 186,43, considerando todos os folículos. Os resultados mostram que houve uma expressão diferenciada de proteínas nas diferentes categorias de folículos. / The estrous cycle of the cow consists of 2-3 follicular waves, in which several follicles are recruited and initiate growth. During the period called follicular deviation, one follicle becomes dominant and the other come into atresia.This process involves mechanisms not yet fully understood, including specific proteins as already determined by gene expression. As a result, the objective of this study was to characterize the proteins of the follicular fluid to identify macromolecules related to the development of follicles from Zebu cow. The ovaries of nonpregnant cows 25 were harvested. The presence of luteum body was noted for each ovary. Follicular fluid was collected using ultrasound. According to the measurement of follicular diameter was 3 separate groups, small follicles (≤6,5mm, n = 28), medium (> 6.5mm to ≤9mm, n = 7) and large (> 9,0mm, n = 11). After 2 centrifugations (600xg / 10 minutes, 15.000xg / 30 minutes, 4 ° C) the supernatant was separated and used for determination of total protein concentration (Bradford method). Electrophoresis was conducted under denaturing and reducing conditions on polyacrylamide separating gel at 12%. The concentration of progesterone and follicular fluid estradiol was determined to identify healthy follicles. The differential proteins identified by electrophoresis will be submitted for MALDI TOF MS / MS approach and gene ontology will be investigated in the databases available. They found 45 protein bands in electrophoresis in 45 follicular fluid samples. The mean ± standard deviation of progesterone concentration was 129.91 ± 186.43 considering all follicles. The results show that there was a differential expression of proteins in different categories of follicles.
169

Relação entre os hormônios metabólicos IGF-1, leptina e GH e eficiência reprodutiva em fêmeas Nelore / IGF-1, leptin and GH concentrations and its effects on reproduction in Nellore cattle.

Peres, Rogério Fonseca Guimarães [UNESP] 12 December 2016 (has links)
Submitted by ROGÉRIO FONSECA GUIMARÃES PERES null (rfgperes@yahoo.com.br) on 2017-01-14T21:47:17Z No. of bitstreams: 1 OK Tese Doutorado com Ficha Catalográfica Rogerio Peres Final.pdf: 3471137 bytes, checksum: afcec40d26ee7845fa56d00b5abdc36e (MD5) / Approved for entry into archive by LUIZA DE MENEZES ROMANETTO (luizamenezes@reitoria.unesp.br) on 2017-01-17T14:03:15Z (GMT) No. of bitstreams: 1 guimaraes_rf_dr_bot.pdf: 3471137 bytes, checksum: afcec40d26ee7845fa56d00b5abdc36e (MD5) / Made available in DSpace on 2017-01-17T14:03:15Z (GMT). No. of bitstreams: 1 guimaraes_rf_dr_bot.pdf: 3471137 bytes, checksum: afcec40d26ee7845fa56d00b5abdc36e (MD5) Previous issue date: 2016-12-12 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Os hormônios metabólicos IGF-1, GH e leptina são alterados de acordo com o status nutricional dos animais. O objetivo desse trabalho foi determinar as concentrações desses hormônios em vacas paridas e novilhas Nelore entre 12 e 16 meses de idade e seus efeitos na reprodução nos experimentos do Capítulo 2. No Capítulo 3, vacas primíparas, multíparas e novilhas Nelore de dois anos foram suplementadas ou não com milho moído durante o protocolo de IATF até o diagnóstico de gestação com o intuito de avaliar a alteração nos hormônios metabólicos e seus impactos na reprodução. No Capítulo 4, multíparas Nelore de duas fazendas foram suplementadas ou não com virginiamicina adicionada ao sal mineral. Em todos os experimentos as fêmeas foram submetidas a protocolos de IATF e colocadas com touro até o fim da estação de monta, sendo que apenas nos experimentos do Capítulo 3, as fêmeas receberam segunda IATF caso estivessem vazias antes da entrada dos touros. No experimento 1 do Capítulo 2 e no experimento 1 do Capítulo 3 houve efeito linear positivo da concentração de IGF-1 no dia da inseminação na probabilidade de prenhez a IATF. Em todos os experimentos realizados, também houve efeito linear positivo da concentração de IGF-1 no dia da inseminação na probabilidade de prenhez ao final da estação de monta, exceto no experimento 2 do capítulo 2. A concentração de IGF-1 no diagnóstico de gestação apresentou efeito linear negativo na probabilidade de prenhez em quatro estudos. O efeito do GH e da leptina nos parâmetros reprodutivos não foi consistente entre os estudos. A suplementação com milho não alterou a taxa de prenhez à IATF, mas houve tendência no aumento da prenhez na segunda inseminação e aumentou a taxa de prenhez ao final da estação de monta de primíparas, diminuiu a taxa de prenhez ao final da estação de monta em multíparas e aumentou somente o peso a desmama dos bezerros de primíparas. A suplementação com virginiamicina não aumentou a taxa de prenhez a IATF e ao final da estação de monta na Fazenda A, enquanto que na fazenda B não aumentou a taxa de prenhez a IATF, mas aumentou a porcentagem de fêmeas ciclando no diagnóstico de gestação e uma tendência no aumento da probabilidade de prenhez ao final da estação de monta. O peso a desmama aumentou em ambas fazendas com suplementação de virginamicina. Conclui-se que o IGF-1 no momento da IA e no momento do DG são possíveis importantes marcadores de fertilidade em bovinos e que estratégias nutricionais podem alterar esses hormônios com ou sem impacto na reprodução. / The metabolic hormones IGF-1, GH and leptin change according to nutritional managmentof the herd. The aim of these trials was to measure the concentration of these metabolic hormones in 12-16 months old Nellore heifers and multiparous cows and associate with the reproduction performance in experiments of Chapter 2. In Chapter 3, 2-years old heifers, primiparous and multiparous Nellore cows received or not ground corn starting in the begginning of TAI protocol until pregnancy check on day 30 to associate with metabolic hormones and reproduction. In Chapter 4, multiparous Nellore cows of two farms were supplemented or not with virginiamycin in mineral salt and the association with metabolic hormores and reproduction was evaluated. In all studies TAI was performed and bulls stayed from 7 days after TAI until the end of breeding season, except on trials of Chapter 3, which second TAI was performed in open cows before being exposed to bulls. In experiment 1 of Chapter 2 and experiment 1 of chapter 3 there was a linear positive effect of IGF-1 concentration on day of insemination on TAI pregnancy rate. In all trials, IGF-1 concentrations on insemination had a linear positive effect on pregnancy rate in the end of breeding season, except in experiment 2 of chapter 2. The IGF-1 concentrations on pregnancy rate had a linear negative association with TAI pregnancy rate in 4 studies. Concentraions of GH and leptin had no consistent association with reproduction rates. Corn supplementation did not alter TAI pregnancy rate, but tended to improve pregnancy rate on second AI and increased final pregnancy rate in primiparous cows, reduced final pregnancy rate in multiparous cows and increased weaning rate of primiparous calves supplemented with corn. Virginiamycin supplementation did not increase TAI and final pregnancy rates in farm A, while farm, B did not increase TAI pregnancy rate, but increased the percentage of cycling cows on pregnancy check and tended to increase final pregnancy rate in the end of the breeding season. In both farms, calves weaning weight increased with virginiamycin supplementation. In conclusion, IGF-1 concentrations on TAI and pregnancy check can be possible markers for fertility in Bos indicus cows and nutritional strategies can change metabolic hormones affecting or no reproduction parameters. / FAPESP: 2014/03209-0
170

Estudo proteômico do desenvolvimento folicular de vacas zebuinas não gestantes

Lourenço, Tarcísio Torre January 2016 (has links)
Orientador: Fabiana Ferreira de Souza / Resumo: O ciclo estral da vaca é composto por 2-3 ondas de crescimento folicular, no qual vários folículos são recrutados e iniciam um novo crescimento. Durante o período denominado desvio folicular, um folículo se torna dominante e os outros entram em atresia. Este processo envolve um mecanismo ainda não completamente compreendido, incluindo proteínas específico, como já estabelecido pela expressão gênica. O objetivo do presente estudo foi caracterizar as proteínas do fluído folicular a fim de identificar macromoléculas relacionadas ao desenvolvimento dos folículos de vacas zebuínas nã-gestantes. Foram colhidos os ovários de 25 vacas mestiças não-gestantes em um abatedouro. A presença do corpo lúteo foi anotada para cada ovário. O líquido folicular foi colhido utilizando-se a imersão do ovário em meio líquido e ultrassonografia. De acordo com a mensuração do diâmetro folicular, foram formados 3grupos, folículos pequenos (≤6,5mm, n=25), médios (>6,5mm a ≤9mm, n=9) e grandes (>9,0mm, n=11). Após 2 centrifugações (600xg/10 minutos e 15.000xg/30 minutos, 4ºC) o sobrenadante foi separado e utilizado para determinação da concentração de proteína total (método de Bradford). A eletroforese foi conduzida sob condições desnaturantes e redutoras, em gel de separação de poliacrilamidaà 12%. A concentração de progesterona e estradiol do líquido folicular foi determinada a fim de identificar os folículos saudáveis. As proteínas diferenciais identificadas pela eletroforese foram... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre

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