Evaluation of cow genotypes by kappa-casein of dairy breeds

Abstract

The polymorphism of the kappa-casein gene (CSN3) has been studied in cows of the Lebedyn, Simmental, Ukrainian Black-and-White dairy breeds using a real-time polymerase chain reaction. The TaqMan® SNP Genotyping Assays use TaqMan® 5´-nuclease chemistry for amplifying and detecting specific polymorphisms in purified genomic DNA samples. All assays are developed using Life Technologies robust bioinformatics assay design process relying on a pipeline using heuristic rules deduced from both manufacturing and assay performance data. The objective of our study is to evaluate the cattle of Ukrainian domestic dairy breeds according to the kappa-casein genotype. It has been shown that the distribution of genotype frequency differs significantly in different breeds: Lebedyn – 19% A/A, 50% A/B and 31% B/B; Ukrainian Brown dairy – 30% А/А, 41% A/B and 30% B/B; Simmental – 44% A/A, 46% A/B and 10% B/B; Ukrainian Black-and-White dairy – 58% A/A, 27% A/B and 15% B/B. The results obtained indicate the prospects of breeding work towards creating herds with the BB genotype in the Brown cattle. The accelerated formation of the desired genetic combinations in micropopulations (herds), with the needs of the processing industry, primarily cheesemakers, is possible in the population of the Brown and Lebedyn breed. Such work with dairy herds of the Ukrainian Black-and-White and Simmental breeds requires more time for selection due to the low frequency of BB genotypes in cattle of these breeds.

Keywords: genetic polymorphism, kappa-casein, genotype, breed