Evaluation of Allelic and Genotypic Diversity of Cattle of Yakutia on Milk Productivity Gene

Abstract

In the studied populations of cattle of Yakutia we revealed two alleles of kappa-casein genes – A and B, and three genotypes – AA, AB and BB. Frequency of the A allele was higher in comparison with the B allele and varied depending on the breed from 0.50 to 0.73. Among the studied breeds cattle with genotype AA found mostly in Austrian Simmental breeding (55%) and Kholmogory (50%). Required for the production of cheese genotype BB 25% of Kalmyk breed cows had and 10% of the Austrian Simmental breed. According to the beta-lactoglobulin gene, the frequency of allele B is prevalent in Kholmogory cows (0.60), Simmental local selection (0.65), and especially in cows Kalmyk breed (0.83). Cows of Simmental Austrian selection have gene of beta-lactoglobulin predominantly with genotype AB (55%) and AA (30 %). The Kalmyk breed prevailed with BB genotype (67 %) and not found the cows with genotype AA. In respect of prolactin gene it has been found that all investigated cattle breeds, the frequency of allele A (0.79  0.98) dominates the fre- quency of allele B (0.02 ... 0.21). In the studied group of Kholmogory breed cows we revealed 10 different combinations of genotypes CSN/LGB/PRL. More frequent there are cows with genotype CSN^AB/LGB^BB/PRL^AA (26.7%). Preliminary studies of milk production showed that animals with genotype CSN^AB/LGB^BB/PRL^AA had the highest milk yield (3578 kg), and the animals with genotype CSN^AА/LGB^АB/PRL^AA – the lowest (2170 kg). More milk fatness was observed for cows with genotype CSN^AB/LGB^BB/PRL^AA (123.8 kg).