Selection of the terminal sire and dam breeds of sheep and its impact in commercial crossbreeding
1999
Pribyl, J. | Milerski, M. | Pribylova, J. (Vyzkumny Ustav Zivocisne Vyroby, Prague-Uhrineves (Czech Republic)) | Mares, V. | Pindak, A.
The effect of selection in sheep is modelled by using the deterministic approach of G-flow method totally for breeding and commercial flocks. Selection is aimed at the group of economically important traits: daily gain, carcass quality, fleece weight, conception rate, litter size, losses of lambs during a rearing period and number of lambings per ewe and year. Four variants of breeding are compared: 1) variant which considers only one meat breed (paternal) both in nucleus and commercial flocks, 2) only one prolific breed (maternal) both in nucleus and commercial flocks, 3) crossing of the sire (meat) and dam (prolific) breeds, 4) like variant 3, but with multiplicative flock for dam breed. The total net income per 1 ewe in the whole system was -352 Czech crowns (Kc) for variant 1, -67 Kc for variant 2, +44 Kc for variant 3, and +57 Kc for variant 4.
显示更多 [+] 显示较少 [-]