Milk of Polish Red and White cows as a source of nutritionally valuable fatty acids
Abstract. Local bovine breeds are usually more resistant to diseases and better adapted to environmental and nutritional conditions than the imported ones. The aim of this study was to assess the content of individual health-related fatty acids in milk of Polish Red and White breed regarding the composition of forages. One herd of cows (n=15) were fed seasonally using locally produced forages: grazed grass, containing high amounts (55 g·100 g-1 fatty acid on average) of polyunsaturated fatty acid, and preserved forages, rich in saturated fatty acid (30 g·100 g-1 fatty acid on average). The content of butyric acid in milk averaged 4.21 g·100 g-1 fatty acid regardless of season and was higher compared to that reported for other breeds. Milk from the summer season had high content (14.67 g·100 g-1 fatty acid) of total short-chain saturated fatty acid (C4:0-C12:0), that from non-pasture season (winter) had high content of odd- and branched chain fatty acids (6.28 g·100 g-1 fatty acid). Milk fat of studied cows had relatively lower content of nutritionally controversial myristic C14:0 and palmitic C16:0 acids as comparing to milk in other breeds and proved an excellent source of vaccenic acid trans-11 C18:1 and conjugated linoleic acids cis-9, trans-11 C18:2, especially during the grazing season.