Influence of degrees of inbreeding on the economic and useful qualities of dairy cattle

Studies were conducted to determine the relationship between the method of breeding, the reproductive qualities of heifers and their subsequent milk productivity in the conditions of enterprises of the Omsk region. It was found that the best characteristics of reproductive qualities are heifers with an inbreeding coefficient of up to 6.25% or with moderate inbreeding and inseminated from 13 to 18 months of age. With increasing homozygosity of organisms, the level of milk productivity decreases.

Rating assessment of breeding bulls of the Kholmogorskaya breed in terms of reproductive indicators in foreign and domestic breeding

The article presents the results of rating assessment of breeding bulls of the Kholmogorskaya breed in terms of reproductive indicators in foreign and domestic breeding in the North-West zone of the Russian Federation. The studies were conducted on the basis of a rating developed in the Northwest Research Institute of Dairy and Grassland Economy. 765 daughters of 18 domestic breeding bulls and 14 of foreign breeding bulls were observed. The rating of breeding bulls is established on reproductive signs of daughters.

Technological aspects of increasing the productive longevity of dairy herds

The research has been carried out to establish the duration of productive use of breeding stock in the breeding farms of the Omsk region. As far as the productive use duration, the cows kept in free stall housing are found to have a significant advantage compared to the tied cows, the difference being 177 days or 17.2 %. A negative correlation has been established between the abundance of milk and the duration of productive use of cows in tied herds.


The impact and results of using sires in dairy cattle populations in the Vologda region

Studies were conducted on controlled populations of dairy cattle of

Ayrshire, Kholmogory, Yaroslavl, black-and-white breeds of breeding farms in the

Vologda region. It has been revealed that the sires of domestic selection have a greater

degree of influence on the productive indices of their daughters than foreign ones do.

The calculation of the breeding value of bulls in terms of their daughters’ productivity

has been carried out, and on the basis of a comparative analysis the best producers

Selection of parent pig pairs by resistency indexes

In 2015, 18 sows of a large white breed, 72 piglets obtained from these sows and 18 boars from another farm, whose sperm was taken for fertilization of sows, were examined in the Kislov individual entrepreneur farm by resistance indicators. On the basis of blood indices, a new selection index of resistance was developed, which includes bactericidal, complementary and lysozyme activity of blood serum, phagocytic activity and index, taking into account the coefficients of heritability of each feature. Parent pairs were selected for resistance indices, which had a positive effect.

Methods of estimation and selection of pigs by resistance indices

The article deals with the study carried out on the sows of a large white breed and their offsprings. It has been established that the sow resistance is positively associated with their reproductive qualities. A new breeding resistance index is developed. Selecting of one-month old replacement gilts of a large white breed by the new methods of resistance has had a positive result.

Comparative Evaluation of the Productive Characteristics in Holstein Heifers of Different Selections under the conditions of the Volga Region Forest Steppe

Modernization of cattle breeding industry in Russia is done by creation of a large dairy farms wide network and active breeding of highly productive cattle. During the formation of highly productive herds on dairy farms and complexes is necessary to consider the imported cattle adaptation to the specific conditions of different regions.

The results of crossbreeding black-and-white cattle and the Holstein breed in the Vologda region

The article presents the results of crossbreeding black-and-white cattle breed and the Holstein one: population and level of milk production change in holsteinized cattle. It has been found that increasing consanguinity of Holstein breed affects milk yield raising. Moreover, the fat and protein content in milk of different cows genotypes varies slightly. It has been proven that the crossbreeding of black-and-white cattle with the Holstein breed is effective.

Desk02 theme