Polymorphism of the GH, TG, and LEP genes and its relationship to body weight in young kazakh white-headed cattle

The research evaluated the results of DNA testing in the selection of parental pairs in young cattle of meat production. The paper describes the heritability of breeding-significant alleles in the GH, TG, and LEP genes responsible for meat productivity, and the association of the presence of desirable marker (GH V , TG T , LEP T ) alleles in young Kazakh white-headed cattle with live weight. So, when selecting cows (n = 20) with complex (GH LV TG CC LEP CC ; GH LL TG CC LEP CT ; GH LV TG TC LEP CC ; GH LV TG CC LEP CT ; GH VV TG CC LEP CC ; GH VV TG CC LEP CT ; GH LL TG TC LEP TT ; GH VV TG TC LEP CC ; GH VV TG CC LEP TT ; GH VV TG TC LEP TT ) with genotypes carrying from one to five selectively significant alleles, and breeding bulls (n = 2) with gene complexes (GH VV TG TT LEP CT and GH LV TG TC LEP CC ) with five and two marker alleles, parental pairs were formed and offspring (F1) with different gene complexes were obtained. As a result of the genotyping of offspring (F1), it was revealed that individuals with four markers in their gene complex (GH LV TG TC LEP ТT ; GH VV TG TC LEP CT ; GH VV TG TT LEP CC) desirable alleles for three genes had a greater live weight at 205 days (218.75 kg for bulls and 197.15 kg for heifers) than carriers of one desirable (GH LL TG CC LEP СT ) allele – 183.00 kg. The average daily increase was also different and ranged from 775.61 to 933.51 grams, depending on the heritability of the number of breeding-significant alleles for the studied genes.