Characteristics of technological and productive indicators of primiparous cows of different types of stress resistance in robotic milking system

The article studies the technological and productive qualities of first-calf heifers of different types of stress resistance under conditions of their operation in robotic milking systems. The studies were conducted at the peasant farm "Mukhametshin Z.Z." of the Republic of Tatarstan on Holstein dairy cows. The assessment of cows' stress resistance was carried out in the first 150 days of lactation based on the inhibition of the milk letdown reflex during unsuccessful (incomplete) milking used as a stress exposure, by the intensity of milk secretion and the rate of milk formation before and after the stress exposure. It was found that the frequency of milking in cows, regardless of the type of stress resistance, was the same 2.9-3.0 times/d. Primiparous cows of high type exceeded animals of medium and low types of stress resistance in single milk yield by 4.8 and 7.9%, milking time - 1.8 and 11.5%, milk secretion intensity - 2.5 and 24.4%, respectively. At the same time, cows of the high type turned out to be more productive in terms of milk yield for 305 days of lactation by 8.0-11.9%, and average daily milk yield by 6.8-11.2% than animals of medium and low types of stress resistance. Thus, the assessment of the technological and productive qualities of cows of different types of stress resistance makes it possible to more effectively form a herd of animals of the technological type, capable of more fully realizing their high genetic potential.