Use of bulls-producers of various origin on the breeding stock of the Yaroslavl breed of the Vologda region

Abstract

The research was conducted in order to study the breeding value of bulls-producers of various origins, used in the breeding stock of cows of the Yaroslavl breed in the Vologda region. The work was done on the basis of the information analytical system «Seleks» for 52 bulls-producers of Yaroslavl and Holstein breed obtained in different countries of the world and used the herd of 1600 cows dairy cattle breeding farm ZAO Sheksna Vologda region. General scientific research methods were used: monographic, statistical, and data visualization. It was found that the used bulls were produced in 5 countries of the world: the USA, Canada, Germany, the Netherlands and Russia. The vast majority of 76.9% of used manufacturers are of domestic origin. It was determined that in the controlled population, the factor «country of origin of the bull» has a significant influence (P<0.001) on the breeding value of producers based on the maternal ancestry (η2=0.46). Bulls from Canada and the United States have the highest indicators of breeding value for the milk yield of their maternal ancestors — 15436 and 14210 kg of milk, respectively. Domestic bulls have a breeding value of 8310 kg of milk, which is 7126 kg less than that of producers from Canada (P ≤ 0.001). The best indicators of bull potential realization by maternal ancestry were found in the daughters of Dutch and Russian producers (64.1% and 69.5%, respectively). The higher-than-average yield for the herd is obtained from cows with a Holstein blood type of 50% or more, using purebred Holstein bulls, both foreign and domestic selection, as well as Yaroslavl bulls with a high degree of blood type for improving breed (75-88%). In order to preserve the Yaroslavl breed of cattle, it is necessary to determine the optimal degree of blood transfusion of the Holstein breed, taking into account not only the productive characteristics, but also the characteristics of the health and longevity of animals.