EN
Fatty Acids (FAs) are a group of compounds with complex structure and different effects on the human organism. There are over 400 FAs in cows milk, many of them as trace amounts. In well fed cows, 95% of milk fat originate from feed and from synthesis in mammary gland, while about 5% come from body fat reserves. There are two ways of FAs formation within the mammary gland. Long-chain FAs originate from triacylglicerols of blood serum, while de nova synthesis of FAs (no longer that 16 carbon atoms in mammary gland cells) is a multi-step process, requiring the activity of numerous enzymes (among others Acetyl-CoA Carboxylase, Fatty Acid Synthase, Stearoyl-CoA Desaturase, Diglyceride Acyltransferase). Every enzyme participating in this synthesis is encoded by a different gene: Acetyl-CoA Carboxylase (1 -ACACA gene, Fatty Acid Synthase - FASN gene, Stearoyl-CoA Desaturase - SCD1 gene, Diglyceride Acyltransferase 1 - DGAT1 gene. Several research show a significant relation between presence of Single Nucleotide Polymorphisms (SNPS) in these genes and FAs profile of cows” milk. Similarly, different non-genetic factors alter the FAs content of milk, one of the most important is nutrition. The FAs profile is affected not only by the type of feed ration (pasture green forage / silage), but also by plant species offered, concentrates share in feed, supplementation with fat or oilseeds, use of Vitamin-mineral complements. Moreover, it changes during lactation and according to body energy status. The aim of this review is to present the recent research concerning generic. physiological and nutritive factors affecting the FAs profile of cows” milk.