The influence of metabolic disorders on the physicochemical and microbiological parameters of milk from highly productive cows

Metabolic processes have a direct connection with milk production. Intensive use of highly productive cows and unbalanced diets affects milk productivity, the sanitary and hygienic quality of milk, as well as the duration of productive use. As a result, the animals' metabolic processes decrease and they are quickly culled. Obtaining high-quality dairy products is the main goal of the country's agro-industrial complex and is strictly regulated by existing standards depending on quality indicators. The research work focuses on changes in physicochemical and microbiological parameters during metabolic changes, which have a huge impact on the physiological state of health of cows and differ in intergroup characteristics. The studies were carried out using laboratory, biochemical, instrumental and statistical research methods. The object of the research was highly productive cows of the Simmental breed of the second calving. The research material was the milk of the studied animals. According to the results of the study, it was revealed that the quality and composition of milk in cows with metabolic alterations tended to change and deteriorate the quality of the finished product. It was found that the titratable acidity of milk tends to increase due to changes in the alkaline reserve of the blood of cows with metabolic disorders, the milk sugar content was reduced by 5% of the norm, and the fat to protein ratio was 1.57, which indicates changes occurring in animal body. The dynamics of a decrease in milk protein by 26% of the norm in the experimental group was revealed, and the fractions of casein and whey proteins were reduced except for γ-casein; an increase in this indicator was revealed, in contrast to other protein fractions. The number of mesophilic aerobic and facultative anaerobic microorganisms in the selected milk samples of experimental animals exceeded the permissible value of 1×105 CFU/cm3 for the highest and 5×105 CFU/cm3 for the first grade, salmonella were absent, the content of somatic cells was 439,19 thousand cells per 1 cm3. The dynamics of an increase in ketone bodies in milk signals metabolic changes that manifest themselves in selected experimental cows in the form of subclinical ketosis.