FADS2-23 POLYMORPHISM: A POTENTIAL MARKER FOR ECONOMIC TRAITS IN HOLSTEIN CATTLE SELECTION

Abstract

Milk composition is nutritionally important to consumers and economically important to producers and processors. Fatty acid desaturase-2 (FADS2) is a component of the lipid metabolic pathway and converts essential fatty acids into long-chain polyunsaturated fatty acids. The work aimed to identify the impact of FADS2-23 marker polymorphism on milk production traits in Holstein cows. We established the genetic structure of the analysed population and the possible relationships between the genetic variants of the FADS2-23 marker and the average breeding values for the traits of milk production. The artificially created restriction site-PCR was used to identify genetic polymorphism for the FADS2-23 marker. We detected all genotypes: AA (8.10%), AG (41.90%), and GG (50%). The allele frequencies were 29.05% for the A allele and 70.95% for the G allele. The Holstein cattle kept in the Slovak Republic exhibit a slight increase in homozygosity (0.5878), polymorphism information content (0.3272), the effective number of alleles (1.7013) and a slight decrease in the level of possible variability realisation (41.42%). We observed a positive effect of the FADS2-23 marker polymorphism on the percentage fat content in the milk of Holstein cows. Genotype AA demonstrably increased the average breeding value for fat content in percent by 0.06% compared to genotype GG. Therefore, the rs109772589 polymorphism in the bovine FADS2 gene may be proposed as a potential genetic marker for fat percentage content in Holstein cattle.