Analysis of the protein content in milk of Black-and-White cows in the herd transformed into dairy type
1998
Hibner, A. | Zieminski, R. (Akademia Rolnicza, Wroclaw (Poland). Katedra Hodowli Bydla i Produkcji Mleka)
The protein content difference between fat and protein contents (RTB) and protein productivity index (IPB) in the herd of 1924 Black-and-White cows improved by crossbreeding with Holstein-Friesian have been studied. It has been stated that in the group of primiparous cows of the fifth generation of crossbreeding the protein content was slightly lower and the protein productivity index was decreasing in the subsequent generations. However, the difference between fat and protein contents increased from 0.80 to 0.98. It has been proved that the cows with low (3.09 percent), compared to high (3.45 percent), lifetime protein content were characterized by a significantly longer period of performance, higher number of calves born and higher milk yield per one year of performance
显示更多 [+] 显示较少 [-]