Trace element status of highly productive cows in different physiological conditions under increased technogenic load

Microelements play a vital role in the maintenance and intensification of metabolic and regulatory processes in the body of animals. For a more complete study of provision of body of highly productive animals with microelements and diagnosis of metabolic disorders, especially under anthropogenic load, it is necessary to conduct biochemical blood tests. The article presents the results of studies on the content of trace elements (iron, copper, zinc, manganese) in the whole blood of cows from two farms in the Voronezh region, one of which (farm 2) is located in an area with increased technogenic load. In whole blood, the content of iron, copper, zinc, and manganese was determined by atomic absorption using a Shimadzu AA-6300 spectrophotometer. Samples were prepared by wet ashing at elevated pressure in a MARS-5 microwave system. Blood samples were taken 2 weeks before calving, one week and one month after calving. A reduced level of copper and zinc was found in animals from both farms throughout the entire study period. The dependence of the content of microelements on the physiological state of animals (before and after calving) was not revealed. It was shown that the content of iron in the blood of highly productive cows from farm 2 was lower throughout the study, and manganese - a week and a month after calving. The amount of manganese in blood of farm 2 animals was less than the lower limit of the physiological norm, while in farm 1 animals its concentration was within the reference normal range.