Hormonal state of the Ural type cows of different linear affiliation depending on milk productivity

The dairy cattle industry is directly related to the correct conduction of breeding work. The content of hormones in the blood serum of cows affects the level and quality of milk. The relationship of hormonal status with signs of milk productivity of cows of different lines was investigated. The purpose of the work was to study the hormonal status of cows of different lines and describe the relationship with milk productivity indicators. The studies were carried out in breeding organizations of the Sverdlovsk region on the livestock of Holstein black-and-white cattle of the Ural type. The selection of animals of the group was carried out by the method of para-analogues taking into account age in lactation, physiological state, breed, live weight, linear affiliation. Milk productivity was based on Selex data. Milk productivity indicators, taken into the account were the following: yield for 305 days of lactation, kg; fat and protein content. Blood was taken from the tail vein of cows into vacuum tubes with k2 edta. The content of prolactin was determined on the device "IMark", with infrared analyzer. The amount of cortisol was assessed on an automatic luminescent analyzer "ADVIA Centaur". Statistical processing of the results was carried out in Microsoft Office Excel, 2010. When calculating the intergroup difference, Student's t-test was taken into account. According to the results of the research, it was found that the cows of the line Vis Back Idial had the best quantitative indicators, the animals of the lines Reflection Sovering and Montvik Chieftain had the best quality indicators of milk. High hormonal status is typical for cows of the Vis Back Idial line. The results obtained indicate the relationship of hormonal status with indicators of milk productivity of cows of different lines.