A Cox proportional-hazards model with time-dependent covariates to evaluate the relationship between body-condition score and the risks of first insemination and pregnancy in a high-producing dairy herd

Autor: Ynte H. Schukken, Witaya Suriyasathaporn, A. Brand, S.J. Dieleman, E.N. Noordhuizen-Stassen, Mirjam Nielen
Rok vydání: 1998
Předmět:
Zdroj: Scopus-Elsevier
ISSN: 0167-5877
DOI: 10.1016/s0167-5877(98)00100-7
Popis: The objective of this study was to determine the relationship between body-condition score and postpartum reproductive efficiency in dairy cattle. Data on body-condition score, reproduction, diseases, and production from 1404 lactations of 639 cows, calving between January 1984 and November 1996 on a commercial farm, were used. The Cox proportional-hazards model with time-dependent covariates was used to qualify the relationship between body-condition score on a scale of 1 to 5 and risks of first insemination and pregnancy. Cows with body condition at calving
Databáze: OpenAIRE
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