Specificities of accumulation of essential polyunsaturated fatty acids of ω-3 and ω-6 families in the tissues of bulls after supplementing their diet with the sources of fatty acids and mineral elements

Aim. To determine the intensity of growth of fattening bulls and the specificities of the accumulation of essential polyunsaturated fatty acids from the ω-3 and ω-6 families in their tissues after supplementing their diet with the sources of essential fatty acids and copper sulfate to increase their meat productivity and improve the biological value of beef. Methods. The study was conducted using the methodological approaches, common for international practice in accordance with the requirements of ISO 17025, and using the conventional methods of peer groups involving clinically healthy animals. The content of polyunsaturated fatty acids of the ω-3 and ω-6 families was determined by gas chro- matography using the Chrom-5 device. Copper content was determined by the method of atomic absorption spectro- photometry using the Selmi C-115 M1 device. Results. It was found that the introduction of linseed oil (as a source of α-linolenic acid, which is a precursor of polyunsaturated fatty acids of the ω-3 family) and sunflower oil (as a source of linoleic acid, which is a precursor of polyunsaturated fatty acids of the ω-6 family), the synthetic substance doxane (as an inhibitor of biohydrogenation processes in unsaturated fatty acids in the rumen) and pentahydrate copper sulfate (as a source of copper) to the diet of young fattening cattle caused a probable increase in the content of biologically active polyunsaturated fatty acids of the ω-3 and ω-6 family and copper in their liver and skeletal muscles. At the same time, the increase in the content of biologically active polyunsaturated fatty acids of the ω-3 and ω-6 families and copper in the abovementioned tissues due to the stimulation of metabolic processes in the body contributed to a probable increase in the average daily weight gain of young fattening animals. Thus, there was a direct relationship between the content of α-linolenic and linoleic acids and copper in the diet and their content in the tissues of experimental animals, productivity characteristics, and biological value of beef. Conclusions. The introduction of a mixture of linseed and sunflower oils into the diet of fattening bulls led to an increase in the content of α-linolenic and linoleic acids and a 1.7-fold decrease in the ratio between essential polyunsaturated fatty acids of the ω-6 family and that of the ω-3 family. The increase in the content of copper and essential polyunsaturated fatty acids of the ω-6 and ω-3 families in the diet of fattening bulls led to their accumulation in the liver and skeletal muscles, which contributed to the enhanced biological value of beef.