Всероссийский научно-исследовательский институт физиологии, биохимии и питания животных – филиал Федерального государственного бюджетного научного учреждения «Федеральный научный центр животноводства – ВИЖ имени академика Л.К. Эрнста»
Kharitonov E.L., Panyushkin D.E.
Institute of Physiology, Biochemistry and Nutrition of Animals,
Borovsk Kaluga oblast, Russian Federation
ABSTRACT. The aim was a systematization of literature and own data of the problem of improving the efficiency of milk formation using lipids in the diet and to produce dairy products with given dietary properties. The main causal factors of variability in milk fat composition are the stage of lactation, feeding, season of the year and the genotype of the animal. The quantitative ratio of fatty acids formed in cows depends on the feeding conditions and on deposited fat reserves. The main factors that contribute to the transformation of feed fat in the rumen are lipolysis, biohydrogenation and fatty acid synthesis by rumen microorganisms. Milk production with controlled composition may be one way to increase the value of milk intended for specific markets. It is therefore necessary to take special measures to protect the polyunsaturated fatty acids in the rumen. Supplementing the protected fatty acids does significantly increase the proportion of C18 isomers: C18, n 9, C18: 2, n 6 and C18:3, n 3, thereby the proportion of saturated fatty acids does decrease, especially C16 and C14 in the milk fat. One reason for the increased consumer demand for cow's milk was the revealing effects useful for human health from fatty acids with conjugated bonds, especially cis-9, trans-11 linoleic acid (conjugated linoleic acid, CLA) contained in cow's milk. The richest natural sources of CLA are meat and milk of ruminant animals. In the beef and cow’s milk the content of CLA is about 0.62% and 0.83% of total fatty acids, respectively, in colostrum − 0.3%. Dairy products (butter oil), made of CLA-enriched milk improve nutritional and physicochemical characteristics, as well as contribute to reduction in low density lipoprotein content in the human blood, which prevents the development of atherosclerosis. Practical recommendations are given on the use of fat supplements in dairy cattle feeding.
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