Scientific Journal of KubSAU

The production of eggs is one of the most important indicators of the productivity of poultry, including chickens The main purpose of breeding chickens in the collections of genetic resources - conservation of genetic diversity. The chickens from the collection of genetic resources it is also possible to receive products, for example, in the form of eggs. The account of the egg productivity of the chickens showed that the intensity of egg production varies among representatives of different directions of productivity. The most stable egg-laying was possessed by chickens of breeds New Hampshire, Black Australian, Dutch white. These breeds are bred as breeds of egg direction of productivity. But they are characterized by long downturns in egg production, lasting more than 7 days. Chickens of meat direction by stable, but low intensity of egg production. All the chickens had a short period For all chickens a short period is characteristic, when the egg-laying is kept at a certain level. It is 30-40 days, after which there is a gradual decrease in this indicator. Such a high level of genetic diversity in egg production in gene pool makes it possible to use this bird as a model object for studying its features

Coloring the plumage of chickens is a complex genetically determined sign. The study of the interactions of the main genes of chicken pigmentation was started by A.S. Serebrovsky. The most complete information on the genes of coloring plumage of chickens and down of chickens is given by Z.M. Kogan, indicating the clutch groups and the arrangement of these genes on the chromosome map. In the 1990s, the interaction of color genes, pen pattern and modifier genes affecting the intensity of the main color and pattern of the pen was described in detail. It was found that in pigs the pigmentation is regulated by the MC1-R melanocortin receptor associated with the locus E. Due to molecular studies, loci of dominant white color (I), recessive white color (c / c), striped pen pattern (B) adherent to the floor , and spotted spot locus (mo). The final phenotype depends not only on individual genes, but also on their interactions and the genetic environment as a whole. The same genes can produce different patterns and shades of the main plumage, and different genes determine the same phenotypes. Despite the fact that there was significant progress in determining the molecular causes of the appearance of a particular type of color in chickens, much remains to be learned

Prolactin (PRL) - is a peptide hormone. It effects on metabolic processes in mammals and birds. Indel genotype mutations in a prolactin gene were determined in 595 hens and cocks. Polymerase chain reaction (PCR) were used. We studied four different breeds: Cornish, White Russian, Pushkin, Yurlov crower. Homozygous of insertion II, homozygous deletion of DD and heterozygous ID were observed in all groups. The differences in frequencies of genotypes and alleles were observed in all groups. Homozygotes II and allele I (frequency is 0,83) were the most common for Russian white chickens with high egg production and the lack of the instinct of incubation. Prolactin gene deletion was more common for beef Cornish. The frequency of D allele was 0,84. Pushkin chickens proved to be closer to the egg type. A significant number of heterozygotes with this mutation were noted in a population of Yurlov crower. It is recommended to use gene prolactin as a marker of productive indicators in chickens