Influence of degree of kinship and genetic similarity on productivity of Siberian Herefords

Abstract

The results of studying the influence of the degree of kinship and genetic similarity of parental pairs on meat productivity of Hereford cattle are presented. An increase in homozygosity in herds of Hereford cattle in Siberia may reduce the effectiveness of breeding work. It was found that the selection of parental couples had a significant effect (p < 0.01–0.001) on the formation of offspring meat productivity. Cows from distant inbreeding and outbred (unrelated) parents were superior in live weight by 31–47 kg at the age of 3 and 5 years compared to closely related ones. The highest live weight ratios (16–66 kg) were observed in young animals obtained from outbred selection of parental couples compared to their peers obtained from closely related mating. Bullcalves from 8 to 15 months old, obtained from mating of unrelated parents, exceeded their peers from closely related mating by 105 g (14%), moderately related – by 87 g (11%) and distant by 69 g (9%). Low values of this indicator for the age-group of up to 18 months result from a large number of factors (genotype, maternal milk production, housing conditions) in the initial stage of organism formation. Bull-calves and heifers with an average degree of genetic similarity of parental couples at all ages had better live weight compared to their peers, due to heredity formed from both parents. A dispersion analysis of the data established a reliable effect (p <0.001) of the degree of genetic similarity of the parental pairs on the amount of live weight. The study of the degree of kinship and genetic similarity of parental pairs will allow to obtain the most accurate and reliable data on the breeding value of Hereford cattle of Siberian selection.