An estimate of breeding values of sires from the fertility of daughters - first-calvers
1991
Polasek, M. (Vyzkumny Ustav pro Chov Skotu, Rapotin (CSFR)) | Cermak, V.
Breeding values of sires were estimated for the parameters of fertility, that means conception and interval from the first to the last insemination. Also heritability of fertility was estimated, on the basis of data acquired in 1986 and 1987 and in the first to fourth months of 1988, from the performance and insemination recording in the Czech Republic. The BLUP method was used in 535 sires to investigate the genetic data on breeding values of the parameters of fertility. In first-calvers the heritability value of conception was h2=0.0177 and that of the interval from the first to the last insemination h2=0.0211. The success of insemination is increasing with the number of inseminations of first-calvers but the interval from the first to the last insemination is getting longer. If the age of first-calvers at the time of insemination is higher than 32 months, the conception rate is increasing. In the first-calvers with the interval from calving to the first insemination shorter than 70 days the success of insemination is getting worse and the interval from the first to the last insemination is getting longer. In the first-calvers with the performance higher than 1,699 kg and more milk over 100 days of lactation the conception rate is lower and the interval from the first to the last insemination is longer. It is necessary to evaluate at least 75 effective daughters to reach an accurate estimate of breeding value.
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