Comparative evaluation of Holstein cows of different genealogical lines by productivity traits

In the Sverdlovsk region Holstein and holsteinized Black-and-White cattle of the Ural type are bred, which officially registered in 2002. In its breeding highly productive Holstein breeding sires were used on the maternal stock of Black-and-White breed of the Ural origin. As a result animals with high productivity indicators were obtained. The purpose of the research was a comparative evaluation of Holstein cows of different genealogical lines affiliation by productivity. It was found that the milk yield for the entire lactation of cows of the genealogical lines Wes Back Ideal 1013415, Montvic Chieftain 95679 and Reflection Sovereign 198998 was higher than the milk yield for 305 days of lactation by 878, 1125 and 1102 kg or by 10.1 %, 13.0 and 12.6 %, respectively, by genealogical lines. The difference was statistically significant in favor of milk yield for the entire lactation (p ≤ 0.01). The lactation duration in cows of different genealogical lines was 419, 411 and 424 days, i.e. the excess of the optimal lactation duration was 114, 106 and 119 days, respectively. The average daily milk yield in the period exceeding the optimal lactation duration was 7.7 kg, 10.6 and 9.3 kg by genealogical lines, respectively. The highest productivity for the entire lactation and for 305 days of lactation was demonstrated by cows of the genealogical line Reflection Sovereign 198998, which was slightly inferior to animals of the genealogical lines Wes Back Ideal 1013415. The genealogical line affiliation of cows affected the reproductive abilities of cows. A tendency for changes in reproductive functions in cows with age was revealed. The best reproductive functions were revealed in cows of the genealogical line Reflection Sovereign 198998.