A comparison of protein polymorphisms in milk produced by two dairy farms in West Pomerania

The aim of the study was to compare the frequencies of protein polymorphisms ill milk produced by cows with various proportion of HF genes within their genotypes, managed ill two farms. Frequency analyses of beta-lactoglobulin (BLG) and three casein tractions (CSN1S1, CSN2, and CSN3) ill individual genetic groups of animals were carried out ill milk of 342 cows. Also, milk content of casein and whey proteins was assayed. The highest level of casein was found ill farm B, in all the genotypic groups Of COWS, while the proportion of whey proteins ill milk was highest in farm A, ill the genotypic group Of COWS with 25% to 50% of HF genes. As far as the remaining groups of cows are concerned, the level of whey proteins was equal in both studied farms. A genetic differentiation of polymorphisms ill milk protein was found ill the analysed farms. Frequency of kappa-casein R (CSN3 B) genetic variants, which are desired in processing, was higher in farm A.