Heritability and reproductive traits of different genotypes of Black-and-White cattle
2001
Petrovic, M. | Lazarevic, R. | Aleksic, S. | Miscevic, B. (Institut za stocarstvo, Beograd - Zemun (Yugoslavia))
Effect of the selection on quantitative fertility traits and their improvement by genetic methods is limited by low heritability values. Investigation of phenotypic and genetic variability of reproductive traits of Black-and-White heifers, that is cows, with different share of present Holstein Friesian genes was carried out on three large public farms in the Republic of Serbia (Yugoslavia). This investigation included 2021 heads of cattle, daughters of 28 bull-sires. Mathematical-statistical analysis of data was performed by use of linear methods (LS-method and BLUP-method). Genotype of a head of cattle, farm and bull-sires caused different variations (P .05, P .05, P .01). Established heritability coefficients for fertility traits had low values, age at first insemination (.146), age at first conception (.132), number of inseminations per one successful conception (.057), age at calving (.127), pregnancy duration (.065) and duration of service period (.099).
显示更多 [+] 显示较少 [-]