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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.
1

Evaluation of 72 h Cosynch and 5 or 7 d post-AI gonadotropin releasing hormone on first service pregnancy rate in lactating dairy cows

Mink, Matthew Ryan 12 June 2006 (has links)
Two studies were conducted to evaluate the effects of 5 or 7 d post-AI GnRH on first service PR, plasma P4, and CL volume in lactating dairy cows synchronized using 72 h Cosynch. All cows were synchronized and randomly assigned to one of three treatment groups: Control – no additional GnRH; 5 d – GnRH 5 d after TAI; 7 d – GnRH 7 d after TAI. In the first study, P4 concentrations were evaluated in samples collected at five separate times and CL volume and number were recorded at 30 d pregnancy examination for Holstein (n = 77) and Jersey (n = 33) cows. GnRH treatment did not affect PR (Control - 47.2%, 5 d GnRH - 40.5%, 7 d GnRH – 44.7%) or P4, but increased TCLV compared to controls (Control – 7.33 cm3, 5 and 7 d GnRH – 10.77 cm3). Incidence of accessory CL increased PR (94.7 vs. 60.6%), P4 (6.95 vs. 5.88 ng/mL), and TCLV (15.51 vs. 6.78 cm3) compared to cows with a spontaneous CL. Cows classified as cycling based on P4 evaluation had significantly higher PR than acyclic cows (54.4 vs. 16.1%). In the second study, Holstein cows (n = 1055) were submitted to the same experimental protocol and evaluated for first service PR. Post-AI GnRH treatment did not significantly affect PR. Primiparous cows (32.8%) tended to have higher PR than multiparous cows (27.6%), but GnRH treatment had no influence on this relationship. In conclusion, GnRH post-AI did not affect PR. Further evaluation of accessory CL incidence is warranted as it significantly affected PR. (Abbreviations: AI – artificial insemination, CL – corpus luteum, PR – conception rate, P4 – progesterone, TCLV – total corpus luteum volume) / Master of Science
2

Expressão dos genes PLCζ, WPB2NL e TNF-α no espermatozoide e suas relações com a qualidade seminal e fertilidade em equinos da raça crioula / Expression of the PLCζ, WPB2NL and TNF-α genes in spermatozoa and its relations with seminal quality and fertility in crioula equine

Bueno, Verônica La Cruz January 2018 (has links)
Em todas as espécies de mamíferos estudadas, o gene PLCζ é responsável pelo aumento de cálcio no momento da fecundação do oócito. Recentemente, o gene WBP2NL, também esta sendo estudado por sua possível capacidade de iniciar a ativação de oócitos. O gene TNF-α é uma citocina pró-inflamatória que pode ser encontrada no plasma seminal, mas seu efeito na viabilidade espermática ainda não está claro. O objetivo desse trabalho foi investigar a expressão dos genes PLCζ, WPB2NL e TNF-α no espermatozoide e suas relações com a qualidade e fertilidade em equinos. Foram utilizados ejaculados de 40 garanhões da raça Crioula, de criatórios localizados próximos a Porto Alegre. A concentração espermática foi avaliada em câmara de Neubauer. As demais análises microscópicas foram realizadas através do Computer Assisted Sperm Analysis AndroVision. A análise da integridade física da membrana foi realizada utilizando-se sondas fluorescentes A integridade funcional da membrana plasmática foi avaliada por meio do teste hiposmótico. Para análise estatística foi utilizada correlação de Pearson, com nível de significância de P<0,05. Foi encontrada correlação positiva do gene PCLζ com integridade funcional da membrana plasmática (0,449), integridade física da membrana plasmática (0,438), taxa de prenhez (0,454), motilidade total (0,486), motilidade progressiva (0,413); correlação negativa com motilidade lenta (-0,427) e espermatozoides imóveis (-0,405). Não foram encontradas correlações dos genes WBP2NL e TNF-α. Concluí-se que a expressão do gene PCLζ no Espermatozoide equino pode ser utilizada com um marcador para a qualidade seminal e fertilidade do garanhão. / In all species of mammals studied, the PLCζ gene is a factor of calcium increase at the time of oocyte fertilization. Recently, the WBP2NL gene is also being studied for its potential ability to initiate oocyte activation during fertilization. The TNF-α is a pro-inflammatory cytokine found in seminal plasma but it effect on motility and viability sperm still unclear. The aim of this study was to verify the expression of PLCζ, WPB2NL and TNF-α genes in spermatozoa and their relationship with quality and fertility in horses. We used the ejaculates of 40 Crioulo stallions, were used from horse farms located near Porto Alegre. After semen collection, the ejaculate was diluted in a commercially available extender. Microscopic analysis of total and progressive motility was performed using a computer assisted sperm analysis system AndroVision. Membrane physical integrity was assessed by fluorescent probes and membrane functionality was analyzed by the hypo-osmotic test (HOST) Statistical analysis was performed using the Pearson correlation, with a significance level of P<0.05. A moderate positive correlation of the PCLζ gene was found with functional plasma membrane function (0.449), physical organization of the plasma membrane (0.438), conception rate (0.454), total motility (0.486), progressive motility (0.413) and negative correlation with slow motility (-0.427) and spermatozoa properties (-0.405). No correlation on WBP2NL and TNF-α genes were found, showing that those genes expression should not be used as a marker of seminal quality and fertility in stallions. It can be concluded that expression of the PCLζ gene on equine spermatozoa can be used as a marker for seminal quality and fertility in the stallion.
3

Expressão dos genes PLCζ, WPB2NL e TNF-α no espermatozoide e suas relações com a qualidade seminal e fertilidade em equinos da raça crioula / Expression of the PLCζ, WPB2NL and TNF-α genes in spermatozoa and its relations with seminal quality and fertility in crioula equine

Bueno, Verônica La Cruz January 2018 (has links)
Em todas as espécies de mamíferos estudadas, o gene PLCζ é responsável pelo aumento de cálcio no momento da fecundação do oócito. Recentemente, o gene WBP2NL, também esta sendo estudado por sua possível capacidade de iniciar a ativação de oócitos. O gene TNF-α é uma citocina pró-inflamatória que pode ser encontrada no plasma seminal, mas seu efeito na viabilidade espermática ainda não está claro. O objetivo desse trabalho foi investigar a expressão dos genes PLCζ, WPB2NL e TNF-α no espermatozoide e suas relações com a qualidade e fertilidade em equinos. Foram utilizados ejaculados de 40 garanhões da raça Crioula, de criatórios localizados próximos a Porto Alegre. A concentração espermática foi avaliada em câmara de Neubauer. As demais análises microscópicas foram realizadas através do Computer Assisted Sperm Analysis AndroVision. A análise da integridade física da membrana foi realizada utilizando-se sondas fluorescentes A integridade funcional da membrana plasmática foi avaliada por meio do teste hiposmótico. Para análise estatística foi utilizada correlação de Pearson, com nível de significância de P<0,05. Foi encontrada correlação positiva do gene PCLζ com integridade funcional da membrana plasmática (0,449), integridade física da membrana plasmática (0,438), taxa de prenhez (0,454), motilidade total (0,486), motilidade progressiva (0,413); correlação negativa com motilidade lenta (-0,427) e espermatozoides imóveis (-0,405). Não foram encontradas correlações dos genes WBP2NL e TNF-α. Concluí-se que a expressão do gene PCLζ no Espermatozoide equino pode ser utilizada com um marcador para a qualidade seminal e fertilidade do garanhão. / In all species of mammals studied, the PLCζ gene is a factor of calcium increase at the time of oocyte fertilization. Recently, the WBP2NL gene is also being studied for its potential ability to initiate oocyte activation during fertilization. The TNF-α is a pro-inflammatory cytokine found in seminal plasma but it effect on motility and viability sperm still unclear. The aim of this study was to verify the expression of PLCζ, WPB2NL and TNF-α genes in spermatozoa and their relationship with quality and fertility in horses. We used the ejaculates of 40 Crioulo stallions, were used from horse farms located near Porto Alegre. After semen collection, the ejaculate was diluted in a commercially available extender. Microscopic analysis of total and progressive motility was performed using a computer assisted sperm analysis system AndroVision. Membrane physical integrity was assessed by fluorescent probes and membrane functionality was analyzed by the hypo-osmotic test (HOST) Statistical analysis was performed using the Pearson correlation, with a significance level of P<0.05. A moderate positive correlation of the PCLζ gene was found with functional plasma membrane function (0.449), physical organization of the plasma membrane (0.438), conception rate (0.454), total motility (0.486), progressive motility (0.413) and negative correlation with slow motility (-0.427) and spermatozoa properties (-0.405). No correlation on WBP2NL and TNF-α genes were found, showing that those genes expression should not be used as a marker of seminal quality and fertility in stallions. It can be concluded that expression of the PCLζ gene on equine spermatozoa can be used as a marker for seminal quality and fertility in the stallion.
4

Densidade nutricional da dieta e taxa de concepção de fêmeas bovinas

Losi, Tiago Creste [UNESP] 17 May 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-05-17Bitstream added on 2014-06-13T18:31:49Z : No. of bitstreams: 1 losi_tc_me_botfmvz.pdf: 145179 bytes, checksum: 36001c2bbef38cbaa0f2ea6f0ebc1faf (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / O objetivo do trabalho foi avaliar o efeito de dietas com diferentes densidades nutricionais na taxa de concepção (TC) de fêmeas bovinas. O trabalho foi realizado na Agropecuária Água Preta, Cocalinho, MT. Foram utilizadas 220 fêmeas Nelores vazias, mantidas em confinamento a céu aberto, com escore de condição corporal (ECC) médio de 2,79, alojadas aleatoriamente em duas baias. Todos os animais receberam dieta de adaptação (DA) por 15 dias, apresentando 50,1% de Fibra em Detergente Neutro (FDN) e 28,8% de Carboidrato Não Estrutural (CNE). No dia 0 a dieta do Tratamento A foi alterada (TA = dieta com maior densidade nutricional - 43,9% de FDN e 35,5% de CNE) e o Tratamento B continuou a receber a DA (TB = dieta com menor densidade nutricional). A dieta total, composta por: silagem de sorgo, sorgo integral triturado, arroz integral triturado, caroço de algodão e núcleo mineral, foi oferecida 4 vezes ao dia aos animais. No dia 0 inciou-se o período de monta (PM), no qual 4 touros nelores e 4 touros cruzados foram colocados junto às fêmeas em cada baia, permanecendo por 22 dias. No dia 21 os touros foram retirados de ambos os tratamentos. Os animais foram observados durante o PM, e somente as fêmeas que foram cobertas permaneceram no experimento. O diagnóstico de gestação (DG) foi realizado por ultra-sonografia 27 dias após a retirada dos touros. A TC foi analisada por regressão logística, por meio dos procedimentos LOGISTIC do SAS. Foram incluídos no modelo os efeitos das variáveis: tratamento, fase (fase 1, do dia 0 ao dia 10 do PM e a fase 2, do dia 11 ao dia 21 do PM) e interação fase x tratamento, e das co-variáveis: ganho de peso médio diário (GMD) e ECC. Foi detectada tendência (P=0,077) de efeito de tratamento na TC (TA=65,7 vs TB=76,1%). Não houve efeito de fase e da interação fase x tratamento. O GMD não foi diferente entre TA e TB, porém foi...
5

Expressão dos genes PLCζ, WPB2NL e TNF-α no espermatozoide e suas relações com a qualidade seminal e fertilidade em equinos da raça crioula / Expression of the PLCζ, WPB2NL and TNF-α genes in spermatozoa and its relations with seminal quality and fertility in crioula equine

Bueno, Verônica La Cruz January 2018 (has links)
Em todas as espécies de mamíferos estudadas, o gene PLCζ é responsável pelo aumento de cálcio no momento da fecundação do oócito. Recentemente, o gene WBP2NL, também esta sendo estudado por sua possível capacidade de iniciar a ativação de oócitos. O gene TNF-α é uma citocina pró-inflamatória que pode ser encontrada no plasma seminal, mas seu efeito na viabilidade espermática ainda não está claro. O objetivo desse trabalho foi investigar a expressão dos genes PLCζ, WPB2NL e TNF-α no espermatozoide e suas relações com a qualidade e fertilidade em equinos. Foram utilizados ejaculados de 40 garanhões da raça Crioula, de criatórios localizados próximos a Porto Alegre. A concentração espermática foi avaliada em câmara de Neubauer. As demais análises microscópicas foram realizadas através do Computer Assisted Sperm Analysis AndroVision. A análise da integridade física da membrana foi realizada utilizando-se sondas fluorescentes A integridade funcional da membrana plasmática foi avaliada por meio do teste hiposmótico. Para análise estatística foi utilizada correlação de Pearson, com nível de significância de P<0,05. Foi encontrada correlação positiva do gene PCLζ com integridade funcional da membrana plasmática (0,449), integridade física da membrana plasmática (0,438), taxa de prenhez (0,454), motilidade total (0,486), motilidade progressiva (0,413); correlação negativa com motilidade lenta (-0,427) e espermatozoides imóveis (-0,405). Não foram encontradas correlações dos genes WBP2NL e TNF-α. Concluí-se que a expressão do gene PCLζ no Espermatozoide equino pode ser utilizada com um marcador para a qualidade seminal e fertilidade do garanhão. / In all species of mammals studied, the PLCζ gene is a factor of calcium increase at the time of oocyte fertilization. Recently, the WBP2NL gene is also being studied for its potential ability to initiate oocyte activation during fertilization. The TNF-α is a pro-inflammatory cytokine found in seminal plasma but it effect on motility and viability sperm still unclear. The aim of this study was to verify the expression of PLCζ, WPB2NL and TNF-α genes in spermatozoa and their relationship with quality and fertility in horses. We used the ejaculates of 40 Crioulo stallions, were used from horse farms located near Porto Alegre. After semen collection, the ejaculate was diluted in a commercially available extender. Microscopic analysis of total and progressive motility was performed using a computer assisted sperm analysis system AndroVision. Membrane physical integrity was assessed by fluorescent probes and membrane functionality was analyzed by the hypo-osmotic test (HOST) Statistical analysis was performed using the Pearson correlation, with a significance level of P<0.05. A moderate positive correlation of the PCLζ gene was found with functional plasma membrane function (0.449), physical organization of the plasma membrane (0.438), conception rate (0.454), total motility (0.486), progressive motility (0.413) and negative correlation with slow motility (-0.427) and spermatozoa properties (-0.405). No correlation on WBP2NL and TNF-α genes were found, showing that those genes expression should not be used as a marker of seminal quality and fertility in stallions. It can be concluded that expression of the PCLζ gene on equine spermatozoa can be used as a marker for seminal quality and fertility in the stallion.
6

Effects of prepartum whole cottonseed or whole raw soybean supplementation on response to timed artificial insemination in suckled mature beef cows following ovulation synchronization

Thomas, Melissa Deann January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / K C Olson / Prepartum fat supplementation has been associated with improved reproductive performance by cows managed for AI. Our objective was to evaluate the effects of prepartum supplementation with whole cottonseed or whole raw soybeans on response to ovulation synchronization and timed artificial insemination in mature beef cows. Cows (n = 188; average initial BW = 579 [plus or minus] 54 kg) were stratified by BCS and BW and assigned to 3 supplementation treatments: whole raw soybeans (21.6 % fat, 38.6% CP), whole fuzzy cottonseed (21.7% fat, 21.1% CP), or a 50:50 mixture of ground corn and soybean meal (2.6% fat, 30.6% CP). Supplements were fed at 1.8 kg per animal daily for 45 d before the first projected calving date (April 1). Supplementation was continued until each cow calved; thereafter, all cows received the control supplement until May 1. Ovulation was synchronized using the CoSynch + CIDR protocol and cows were bred via AI on June 21. Eleven d after AI, cows were exposed for natural service breeding for 50 d. Conception to AI was assessed 33 d after AI. Overall conception was assessed and conception to AI reaffirmed 126 d after AI. Body weight of cows fed control or oilseed supplements was similar (P > 0.3) at calving, initiation of ovulation synchronization, and at the end of the breeding season. Cottonseed-supplemented cows lost more BW and more BCS (P < 0.03) from the beginning of the trial to calving than those fed soybeans. Proportion of cycling cows was similar (P = 0.57) between treatments. Pregnancy to timed AI and final pregnancy rates were similar (P > 0.75) between control and oilseed-supplemented cows. Conversely, supplementation with cottonseed was associated with increased AI conception (P = 0.08; 54 and 39%, for cottonseed and soybeans, respectively) and greater final pregnancy rate compared to soybean-fed cows (P = 0.03; 100 and 93% for cottonseed and soybeans, respectively). Calf birth weights and calf weights at the end of the breeding season were similar (P > 0.24) between treatments. Effects of cottonseed and soybean supplementation on response to ovulation synchronization and timed AI by beef cows warrant further study.
7

Densidade nutricional da dieta e taxa de concepção de fêmeas bovinas /

Losi, Tiago Creste, 1980- January 2006 (has links)
Orientador: José Luiz Moraes Vasconcelos / Banca: Mário Binelli / Banca: Mário De Beni Arrigoni / Abstract: The objective of this trial was to evaluate the effects of different nutritional diet density on conception rate (CR) in bovine females. The experiment was achieved at Agropecuária Água Preta, Cocalinho, MT. It was made use 220 no pregnant Nelore females, on average with 2.79 body condition score (BCS), housed at a commercial feedlot, randomly divided in two pens. All animals received an adaptation diet (AP) for 15 days, with 50.1% of Neutral Detergent Fiber (NDF) and 28.8% of Non-Structural Carbohydrate (NSC). On day 0 the diet of Treatment A was changed (TA= higher nutritional density diet - 43.9% of NDF and 35.5% of NSC) and the Treatment B carried on receiving the AD (TB= lower nutritional density diet). The total mixed rate, settled of sorghum silage, sorghum whole cracked, rice whole cracked, cottonseed high lint and minerals, was offered four times a day. On day 0 it started the breeding period (BP), with natural service, using 4 Nelore bulls and 4 crossbred bulls in each pen, until day 21. The females where observed for estrus during the BP and only the cows that presented service were kept on the experiment. The CR was determined 27 days after BP by ultrasound. The CR was analyzed by logistic regression of SAS. The effects of variables: treatment, phase (phase 1, from day 0 until day 10 of the BP; phase 2, grom day 11 until day 21 of the BP) and interactions were included in the model, BCS and body weigh gain (BWG) were included as a co-variables. Tendency (P=0.077) of treatment effect on CR (TA=65.7 vs TB=76.1%) was detected. There was no effect of phase and interaction phase x treatment. The BWG was similar between TA and TB, however a linear effect (P<0.05) of BWG on CR was detected. Effect of BCS was no detect (P>0.10) on CR. As conclusion, the higher nutritional density diet intake decrease the CR. / Resumo: O objetivo do trabalho foi avaliar o efeito de dietas com diferentes densidades nutricionais na taxa de concepção (TC) de fêmeas bovinas. O trabalho foi realizado na Agropecuária Água Preta, Cocalinho, MT. Foram utilizadas 220 fêmeas Nelores vazias, mantidas em confinamento a céu aberto, com escore de condição corporal (ECC) médio de 2,79, alojadas aleatoriamente em duas baias. Todos os animais receberam dieta de adaptação (DA) por 15 dias, apresentando 50,1% de Fibra em Detergente Neutro (FDN) e 28,8% de Carboidrato Não Estrutural (CNE). No dia 0 a dieta do Tratamento A foi alterada (TA = dieta com maior densidade nutricional - 43,9% de FDN e 35,5% de CNE) e o Tratamento B continuou a receber a DA (TB = dieta com menor densidade nutricional). A dieta total, composta por: silagem de sorgo, sorgo integral triturado, arroz integral triturado, caroço de algodão e núcleo mineral, foi oferecida 4 vezes ao dia aos animais. No dia 0 inciou-se o período de monta (PM), no qual 4 touros nelores e 4 touros cruzados foram colocados junto às fêmeas em cada baia, permanecendo por 22 dias. No dia 21 os touros foram retirados de ambos os tratamentos. Os animais foram observados durante o PM, e somente as fêmeas que foram cobertas permaneceram no experimento. O diagnóstico de gestação (DG) foi realizado por ultra-sonografia 27 dias após a retirada dos touros. A TC foi analisada por regressão logística, por meio dos procedimentos LOGISTIC do SAS. Foram incluídos no modelo os efeitos das variáveis: tratamento, fase (fase 1, do dia 0 ao dia 10 do PM e a fase 2, do dia 11 ao dia 21 do PM) e interação fase x tratamento, e das co-variáveis: ganho de peso médio diário (GMD) e ECC. Foi detectada tendência (P=0,077) de efeito de tratamento na TC (TA=65,7 vs TB=76,1%). Não houve efeito de fase e da interação fase x tratamento. O GMD não foi diferente entre TA e TB, porém foi... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre
8

Evaluation of the Nguni cattle reproductive performance in the communal property association and privately owned enterprises across ecological zones of Mpumalanga Province

Sambo, Johan Mackson January 2020 (has links)
Thesis (M.A. Agricultural Management (Animal Production)) -- University of Limpopo, 2020 / The Nguni is indigenous multi-purpose cattle breed that plays an important role in both commercial and communal farming systems in South Africa (SA). Unfortunately, the breed is currently under threat of diminishing due to farmers’ preference for exotic breeds and cross breeding. In recognition of the above, the Industrial Development Corporation, the Mpumalanga Department of Agriculture, Rural Development, Land and Environmental Affairs and the University of Limpopo established the Nguni cattle breed preservation project. In this project, a herd of 30 Nguni heifers and 1 bull were allocated to 34 Communal Property Associations (CPA) and 40 private farming enterprises each. With its three distinct ecological zones (High, Mid and Low-veld), the Mpumalanga province poses a challenge to the Nguni preservation project since cattle have to adapt to different ecological zones in order to grow and reproduce efficiently. Knowledge of cattle herd productivity improves the understanding of the functional attributes and is useful in determining the constraints and the potential of communal beef cattle production systems. Significant differences between ecological zones were observed for age at first calving, weaning rate, calves’ birth weight and calves’ weaning weight (p < 0.05). Calving of heifers in the Mid-veld zone occurred earlier (24 months) on both ownership types compared to Highveld (28.09 months for private and 26.00 for CPA) and the Lowveld (28.35 months for both ownerships). Nguni cattle on the Highveld performed better in terms of weaning rate under both private and CPA ownerships, where the weaning rate were 93% and 80%, respectively. Calves birth weight was lower in both ownership types in the Midveld zone (22.17 kg), whereas in the CPA, the Lowveld zone had higher calves birth weights (26.80 kg). In the private ownership, the highest calves’ birth weight (25.35 kg) was on the Highveld. The calves weaning weight were significantly higher (p < 0.05) on Highveld in private ownership (190.16 kg) and lowest (160.39 kg) in the Midveld zone. For the CPA, the highest calves weaning weight was also on the Highveld (187.55) and lowest on Midveld (167.50 kg). A full range of backup services that are offered to the communities by stakeholders in the form of a beef package that includes veld and pasture management, nutrition management, beef performance, animal recording keeping, genetic evaluation and animal health management program needs thorough attention.

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