THE GENETIC POTENTIAL OF HOLSTEIN BULLS OF DIFFERENT ORIGINS

Abstract

The article presents the results of the analysis of milk productivity of Holstein cows of the Dutch and German breeding, lactating in two breeding herds of Joint-Stock Company (JSC) ”Aydyn”, and Limited Liability Company (LLC) ”Doksancom”. In the herd of JSC ”Aydyn” the cows of the Dutch selection on average significantly exceeded their peers of the German breeding in milk yield for 305 days of lactation by 633.6 kg of milk (P<0.001). The realization of the genetic potential for milk yield during 305 days of lactation was higher at heifers of the Dutch selection and amounted 78.15 %, which is by 8.45 % more than the average at the heifers of the German breeding. With an increase in the number of lactations, in LLC ”Doksancom” experienced an increase in milk yield per lactation. By the second lactation, milk production increased by 1101.6 kg of milk and averaged 10.082 kg of milk per lactation,to the third - by 1549.9 kg of milk, the difference is highly reliable, at Р<0.001. For 7 completed lactations (2135 days), from cow nr. 5736 was received 65274 kg of milk, the average daily milk yield for the entire period was 30.5 kg of milk. The realization of the genetic potential for milk yield in the herd of LLC ”Doksancom” was higher at cows of the third lactation and amounted to 108.3%, which is on average by 7.1% more than at the cows of the first two lactations.

Keywords

• cows
• breed
• lactation
• genetic potential
• milk ratio