Double insemination of cows during one oestrus
2002
Jankowska, M.,University of Technology and Agriculture, Bydgoszcz (Poland). Dept. of Cattle Breeding
Data on insemination and reinsemination were collected from 1 643 Black and White (BW) cows with varied share of Holstein Friesian (HF) genes, which belonged to the active population managed in five large-scale production farms in the Kujawsko-Pomorskie Province, Poland. A total number of 351 repeated inseminations were recorded, which amounted to 7.71 percent of all inseminations. The rates of non-return to oestrus after reinseminations were by 2.05 percent better in relation to single inseminations, however, an economical analysis led to a conclusion that double insemination does not produce economical benefits and can only be recommended in specific cases, e.g. with prolonged oestrus. Highly significant effect on non-return rates after inseminating once or twice was demonstrated for the factors of HF genes share, farm, milk yield, age at first calving, subsequent calving, and season of insemination
显示更多 [+] 显示较少 [-]