The aim of this study was to determine whether genetic differences in genes FABP3 and SLC27A3 may be related to the productivity and composition of sheep's milk. A herd of 50 Slovak sheep breed Zoslachtena Valaska (Zošľachtená Valaška, in Slovak) was studied. The frequencies of the most common alleles were as follows: FABP3 SNP13 0.82, SLC27A3 C/T 0.64, SCL27A3 A/G 0.74. The results of the statistical analysis for polymorphism in the FABP3 (SNP13) gene showed that animals with the homozygous AA genotype had the highest content of fat, protein and solids in the milk of tested sheep. The analysis of the results for the SLC27A3 C/T polymorphism allowed us to conclude that the milk of animals with the homozygous TT genotype was characterized by the lowest content of fat, protein and solids and the highest content of lactose. In the case of SLC27A3 A/G polymorphism, sheep with the heterozygous genotype were characterized by the highest fat content in milk and the lowest content of protein and lactose. The milk of sheep with the heterozygous genotype FABP3 was characterized by the highest share of serum albumin, α+β – caseins and α-lactalbumin. In contrast, animals with the homozygous AA genotype were characterized by the highest content of κ-casein. The relationships between genotypes of the SLC27A3 C/T polymorphism showed that sheep with the heterozygous genotype were characterized by the lowest content of serum albumin, and the highest content of α+β – caseins in milk. The analysis conducted for the SLC27A3 A/G polymorphism demonstrated that animals with the AA genotype were characterized by the lowest content of serum albumin in milk. Because most of the results were not confirmed statistically, we should continue research using different breeds of sheep and herds with a larger number of animals.

22.4.2017