The variability of the fatty acid profile content in cows’ milk in depending on the breed, feeding system, and season

The aim of the study was to determine a level of fatty acid in cows’ milk dependent of on the breed, feeding system and season. The research material consisted of cows’ milk collected from cows from 10 conventional farms in Poland. Cows were fed with haysilage and corn silage (HS, CS) or haysilage (HS) or Total Mixed Ration (TMR). Milk for testing was collected in two feeding seasons: summer and winter, from Holstein-Friesian (HF) and Simmental (SIM) dairy cow breeds. In each feeding season, milk was collected two times, at the same time from each farm (at the beginning of the study period and at the end of each feeding season. The highest average concentration of monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) were observed in milk from SIM cows, while saturated fatty acids (SFA) were found in milk from HF. In the summer season, milk from SIM cows the contents of PUFA and MUFA was: 0.08-0.15 g/100 g and 0.75-1.19 g/100 g, while in milk from HF cows: 0.01-1.14 g/100 g and 0.83-0.97 g/100 g. In milk from HF cows from the summer season, a significantly higher share of SFA acids was noted than in milk from SIM cows. The content of these acids was: HF: 2.39-3.28 g/100 g and SIM: 2.51-2.96 g/100 g, respectively. The analysis of the fatty acid profile of milk from the winter season showed that the average content of MUFA and SFA acids was higher in milk from SIM cows. The obtained values were at the level of 0.64-0.97 g/100 g for MUFA and 2.34-3.26 g/100 g for SFA. At the same time, in milk from HF cows, the level of these acids was: 0.53-0.87 g/100 g and 1.67-2.98 g/100, respectively. In turn, there were more PUFA acids in milk from HF cows 0.08-0.14 g/100 g; than in the milk from SIM cows: 0.08-0.14 g/100 g. Feeding cows with haysilage and corn silage (HS, CS) increased the level of MUFA and PUFA, both in the summer season and in the winter season. In the summer season, the values of these indicators oscillated at the level of: 0.84-1.19 g/100 g, while PUFA 0.08-0.15 g/100 g. In turn, feeding in the TMR system increased SFA both in winter and summer season. The research results indicate that milk from SIM dairy cow breeds contained more PUFA and MUFA, and in the case of the feeding season, milk from the summer feeding season has better properties from cows fed with haysilage and corn silage. In the case of SFA, more of these acids were found when cows were fed TMR.