Creation of a resource population to study the structural variability of the chicken genome and search for gene variants that determine the manifestation of economically beneficial phenotypes of meat productivity

The aim of the study was to obtain phenotypic characteristics of the resource population chickens characterizing the development of the musculoskeletal system and body build for the subsequent study of the structural variability of the chicken genome and the search for gene variants that determine the manifestation of meat productivity phenotypes, including the development of the musculoskeletal system. Materials and methods. The object of the study were chickens of the F0 generation of the Uzbek fighting breed (n = 65) and Cornish (n = 79); hybrids F1 (♂ Cornish x ♀ Uzbek fighting; n = 117) and F2 (♂F1 x ♀ F1; n = 133). At the age of one day, 2 and 4 weeks, the weight (g) of the chickens was determined. Exterior measurements were taken at the age of 4 weeks. The following indicators were estimated (cm): chest girth; metatarsus girth; keel length; metatarsus length. The body conformation indices were calculated. Results. The chickens of the original F0 breeds and F1, F2 hybrids differed significantly in live weight at the age of 2 and 4 weeks. The weight of the Uzbek Fighting breed gene pool chickens was 3,5–4,2 times lower than that of the Cornish breed; the F1 and F2 hybrids had intermediate indicators. In Cornish breed chickens (F0), the coefficient of variability in live weight at the age of 4 weeks was 13,8 %; in Uzbek Fighting breed chickens (F0) – 15,0 %; in F1 and F2 hybrids – 20,5 and 17,6 %, respectively. The maximum values of the massiveness, eirisomy and shortness indices were obtained on Cornish breed chickens, while Uzbek Fighting breed chickens had low indicators; F1 and F2 hybrids are intermediate. Heterosis was established for the relative length of the metatarsus in F1 and F2 hybrids compared to the original breeds. The data obtained proved the feasibility of using the Cornish and Uzbek fighting breeds to create a resource population for the purpose of conducting research to find gene variants that determine the manifestation of meat productivity phenotypes.

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