Breeding and genetic approaches to the breeding of new genotypes of dymorphous geese

Abstract

The breeding and use in industrial and farm goose breeding of geese that are autosex in color of plumage is of great national economic importance due to the reduction of costs for sorting poultry and preventing the transfer of infectious diseases. The developed selection and genetic approaches to the breeding of autosex geese with the desired set of gene markers make it possible to clearly identify the sex of a bird by phenotype at diurnal and adult age. Rhine white (paternal form) and Large gray (maternal form) geese of domestic selection were chosen as the original breeds. Due to the presence in the genotype of all hybrid goslings F₁ only one dose of incompletely dominant gene Sd, all young at the age of one day had a solid gray with yellow wing tips down color. In adulthood, F₁ geese had gray plumage with white first-order feathers, while females were white with dark gray second-order flight feathers on the wings and gray spots on the back. Adult F₂ hybrid males had a solid white plumage, the typical females were also white, but differed from geese by gray first- and second-order feathers on the wings and individual gray spots on the back. As a result of crossing the bird according to the developed complex scheme, hybrid goslings of the third generation (F₃) of 3 genotypes and, accordingly, 3 phenotypes of down color in the section of each sex were obtained. For further work within each sex at day age, males and females F₃ were selected only with a typical (target) colorsex phenotype: males (genotype G/G Sd/Sd Sp/Sp C/C) had a light gray solid color of the dorsal surface of the body, females (G/- Sd/- Sp/Sp C/C) - gray continuous down on a back and a head. At a young and mature age, males had white solid plumage, and females differed from them by gray flight feathers of the first and second order on the wings and, as a rule, the presence of several dark feathers on the back. In the breeding of F₃ geese with a typical autosex genotype "in themselves" received offspring of the next fourth generation (F₄), colorsex in the color of down in the day age, and in the color of plumage - in adults, ie individuals with pronounced sexual dimorphism. The phenomenon of dimorphism (colorsexuality) of geese formed in the newly created population makes it possible to obtain almost 100.0% accuracy in determining the sex of a bird at different stages of ontogenesis.