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Fouz,Ramiro; Gandoy,Fernando; Sanjuán,María Luisa; Yus,Eduardo; Diéguez,Francisco Javier. |
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... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Dairy cattle; Logistic models; Reproductive performance; Sire influence. |
Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2011000600011 |
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