METHODOLOGICAL ASPECTS OF EVALUATING THE EFFECTIVENESS OF THE USE OF BULLS-PRODUCERS OF THE RED-MOTTLED HOLSTEIN BREED

Despite the harsh pressure, it was possible not only to preserve, but also to form a highly productive herd of the red steppe breed with a milk yield of 6940 kg, 700 cows, the highest figure in the North Caucasus Federal District. It was found that to improve the gene pool of the red steppe breed in herds with a milk yield above 6000 kg of milk, it is impractical to use bulls-producers of the red-mottled Holstein breed. The assessment of more than two dozen Holstein bulls convincingly indicates that against the background of up to 70% of the rejection during the first two lactation, the average yield of adult cows stabilizes at less than 6,000 kg and only units of 7 thousand and above. A characteristic feature of crossbred offspring is that in virtually all variants, the best daughters are obtained in combination with average and worst mothers, and vice versa, the offspring of the best mothers are significantly inferior to their peers.