Wydajnosc i jakosc mleka koz o roznych genotypach alfa-s1-kazeiny z rejonu Wielkopolski i Podkarpacia

The aim of the research was to compare milk productivity parameters of goats having different αs₁-casein genotypes from two breeding regions in Poland. 745 goats of four breeds (white and coloured improved, white and coloured common) raised in two breeding regions in Poland, i.e. Podkarpacie and Wielkopolska were studied and their daily yield of milk was compared in relation to the genetic variants of αs₁-casein. It was found that the daily milk yield of goats raised in the Podkarpacie region was higher and had a superior chemical composition compared to that of the goats from the Wielkopolska region. Additionally, in the summer season (regardless of production region and breed) the goats produced milk with higher protein content, including casein. The analysis of the genetic αs₁-casein in relation to the goats’ performance did not indicate its significant influence on milk yield. Nonetheless, there seemed to be a significant tendency for strong variants to have an impact on a higher concentration of the basic milk components, i.e. protein (mainly casein) and fat.