Correlations of the main biochemical and amino acid parameters of cows' milk in winter and spring seasons (post 2)

Abstract

Protein-amino acid and fat composition of cow's milk are one of the important criteria for its evaluation. Although modern publications more and more mention the amino acid (AA) composition of cow's milk, especially for non-replaceable AAs, but in most cases, these works lack correlation coefficients between the main biochemical indicators (including amino acids), which reduces the value of such data. The purpose of this study is to identify correlations between the main biochemical parameters (with an emphasis on amino acids) of the milk of Blackand-White cows in the winter and spring seasons. The studies were carried out with samples of the Ladoga breeding farm (Krasnodar Territory, Ust-Labinsky District). Group 1 (January) included 12 cows, and groups 2, 3 and 4 (February, March and April, respectively) - 22 animals, respectively. The cows were fed according to generally accepted norms. The determination of AA was carried out by ion-exchange chromatography with post-column derivatization of samples with ninhydrin on an LC-20 Prominence system (Shimadzu, Japan) and a column with an ion-exchange resin 4.6x150 mm (Sevko, Russia). Data on the correlation coefficients between the AA of cow milk were obtained. There are practically no results of this kind in the literature. For all groups of the studied samples, positive correlation coefficients were found between the content of AA in the cow milk, mostly very strong (0.76-0.98), strong (0.51-0.75) and moderate (0.25-0.50). For the first time, correlation coefficients (from strong to moderate) between AA and cow milk proteins in the winter and spring seasons were obtained.