Assessment of breeding qualities of agricultural poultry of egg direction productivity (review)

The biological plateau of the formation of full-fledged eggs in chickens is within 365-398 eggs per year, but for now it is unreal to achieve these results with the use of modern methods of breeding and technology. That is why, at present, breeders all over the world have directed their efforts to extend the productive use of hens with a relatively high (not less than 70%) level of egg laying at 76-80 weeks of life. An important direction of selection of egg chickens should be considered an increase in adaptive properties while maintaining productivity. The biological basis for increasing the efficiency of further poultry breeding to increase its egg production is the involvement of genotypes in the selection system based on its assessment throughout the entire period of ontogenesis. Breeding for improving feed-gain relationship in egg farming allows us to hope for the reduction of high cost of birds feedings. However, intensive selection to improve feed-gain relationship can lead to negative phenomena, since chickens lose the ability to eat large doses of feed. One of the important areas of breeding work is the creation of autosexing lines and bird crosses. It is of particular importance for egg poultry in terms of reducing labor costs for sorting chickens by sex and increasing the accuracy of sexing to 98.0-99.5%. An important direction in the genetic improvement of egg productivity of birds is the preservation of their gene pool. Genetic approaches allow to achieve significant success in working with the hens of the egg direction of productivity, as evidenced by the creation of now existing highly productive crosses "Lohmann", "Highsex", "Iza", "Hyline", "UK Kuban", "Rhodonite", etc. However, the problem of genetic improvement of laying hens does not lose its relevance, since the direction of selection does not remain unchanged. The definition of the poultry class in the farm gives an opportunity to judge its breeding value and set appropriate prices when selling products.