Biochemical composition of milk of Tuvinian grunting cows

Abstract

Results are given from investigations into the biochemical composition of milk in grunting cows and cows of Tuvinian population. Experiments were carried out in the Tuvinian highlands in 2010-2015. There were formed two groups of animals: grunting cows and cows, which were under the same keeping and feeding conditions. Biochemical analyses were carried out in a laboratory. Contents of macro and trace elements were determined by the method of atomic absorption: amino acids by amino acid analyzer, vitamins by the method of infrared spectroscopy. It has been found that milk of grunting cows is characterized by higher nutritive value and biological activity. As compared with cow’s milk, it contains more fat, protein and vitamin E by 3.1%, 1.7%, and 1.53 mg/l, respectively. A distinction in the amino acid composition in favor of grunting cows has been found. Essential amino acids played a special role in this regard: as compared with cow’s milk, milk of grunting cows was 0.13% higher in lysine, 0.08% in phenylalanine, and 0.11% in valine. The mineral composition of milk of grunting cows was different from that of cow’s milk, too: the contents of calcium and zinc were 0.13% and 1.75 mg/kg higher, respectively. With that, milk of grunting cows yielded to cow’s milk in the contents of vitamins B6 and B12 by 0.36 mg/l and 0.9 micrograms/l; glutamine was 1.1 times lesser, iron and manganese by 1.73 and 1.21 micrograms per kg, respectively.