Studies on the effects of grading up crossbreeding in dairy cattle herds in Western Pomerania
1998
Kamieniecki, H. | Wojcik, J. | Czerniawska-Piatkowska, E. (Akademia Rolnicza, Szczecin (Poland). Katedra Hodowli, Bydla i Owiec)
The analysis of the lifetime production of cows according to contribution of HF genes (0.25.0, 37.5, 50.0 and 75.0 percent) was carried out based on the results of 2491 primiparous cows coming from 6 herds with different number of animals in each herd, ranging from 95 to 836. Local Black-and-White cows were used for the longest time, as these among hybrids with 50 percent HF gene contribution. Hybrids, though being used for the shortest time than BW cows obtained higher life yields. Indicators of their lactation uniformity and effectiveness were more favourable as well. No closer relationship was found between cow genotype and some fertility indices. Too early and excessive culling of cows was found in all groups, mainly due to health problems, which points to the need of improving maintenance conditions for cows
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