Creation of a breeding group of Hereford cows improved by bulls of canadian reproduction

Abstract

The results of research on the creation of a breeding group of Hereford cows at the Novosibirsk Region breeding reproducer are presented. It was found that cows from the 3rd to 7th calves have the lowest coefficient of variability for live weight (from 1.9 to 2.7%), for milk yield - from 1.9 to 5.6%. The variation in height at hips (characterizing the manifestation of the type) was from 1.3-1.6%. Based on these indicators, a breeding group of 82 cows was selected and evaluated. The average live weight of the animals was 570.5 kg, which exceeds the standard of the breed by 50.5 kg or 9.7%, and corresponded to the elite-record class. The selection differential by live weight of cows of the whole herd and breeding group was 11 kg. Taking into account the coefficient of inheritance and the effect of selection on the first generation to achieve the indicators of the desirable type based on the cows of the breeding group will take 3.5 generations (10.5 years), respectively, for milk yield - 3.9 generations (4.5 years). More effective breeding achievement can be achieved in height at hips (1.1 generations and 3.3 years). Ten stud bulls selected for custom mating are homogeneous and rated elite-record class. They exceeded the breed standard by 151.5 kg (8.1%) in live weight at 3 years of age and by 115.3 kg (14.1%) at 5 years and older. They are characterized by a well-defined desirable type of constitution. Stud bulls obtained from the cross of the Canadian and Siberian selections with the complex index "B", according to the quality of progeny 104-105 recognized as improveers.