| Registro completo |
| Provedor de dados: |
PAB
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| País: |
Brazil
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| Título: |
Factors associated with 56-day non-return rate in dairy cattle
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| Autores: |
Fouz,Ramiro
Gandoy,Fernando
Sanjuán,María Luisa
Yus,Eduardo
Diéguez,Francisco Javier
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| Data: |
2011-06-01
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| Ano: |
2011
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| Palavras-chave: |
Dairy cattle
Logistic models
Reproductive performance
Sire influence
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| Resumo: |
The objective of this work was to identify factors associated with the 56-day non-return rate (56-NRR) in dairy herds in the Galician region, Spain, and to estimate it for individual Holstein bulls. The experiment was carried out in herds originated from North-West Spain, from September 2008 to August 2009. Data of the 76,440 first inseminations performed during this period were gathered. Candidate factors were tested for their association with the 56-NRR by using a logistic model (binomial). Afterwards, 37 sires with a minimum of 150 first performed inseminations were individually evaluated. Logistic models were also estimated for each bull, and predicted individual 56-NRR rate values were calculated as a solution for the model parameters. Logistic regression found four major factors associated with 56-NRR in lactating cows: age at insemination, days from calving to insemination, milk production level at the time of insemination, and herd size. First-service conception rate, when a particular sire was used, was higher for heifers (0.71) than for lactating cows (0.52). Non-return rates were highly variable among bulls. Asignificant part of the herd-level variation of 56-NRR of Holstein cattle seems attributable to the service sire. High correlation level between observed and predicted 56-NRR was found.
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| Tipo: |
Info:eu-repo/semantics/article
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| Idioma: |
Inglês
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| Identificador: |
http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2011000600011
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| Editor: |
Embrapa Secretaria de Pesquisa e Desenvolvimento
Pesquisa Agropecuária Brasileira
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| Relação: |
10.1590/S0100-204X2011000600011
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| Formato: |
text/html
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| Fonte: |
Pesquisa Agropecuária Brasileira v.46 n.6 2011
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| Direitos: |
info:eu-repo/semantics/openAccess
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