THE HEAT STRESS INFLUENCE REDUCTION ON MILK PRODUCTIVITY

Abstract

The article presents the results of research on the reduction of the negative influence of heat stress on the milk productivity of cows in the second half of lactation due to the use of a protein feed additive with protected protein and starch. One of the factors of effective milk production with intensive management of the industry is the creation of comfortable conditions for keeping animals on the farm. Highly productive cows are quite demanding on the conditions of maintenance and microclimate. The study of the productive action of the complex drug Bypass protein + passable starch under the influence of temperature stress was carried out by us for the first time. The influence of the thermal factor of the environment on the productivity of cows is well described in the literature and the mechanisms of such an effect are described. The main consequence of the reaction of cows to temperature stress is a decrease in the consumption of dry matter of feed. This factor becomes the main factor in reducing productivity due to energy and protein deficiency. The same reaction was observed in our studies, both in the control and experimental groups. But we confirmed for the first time that the actions of compensation of temperature stress can be controlled due to the configurations of protein and energy entering the body by bypassing the scar. In our research, it has been proven for the first time that even in the conditions of reduced feed consumption, this way of providing cows with protein and energy is a reliable way of managing the productivity of cows and stabilizing their homeostasis during the period of temperature conditions that are dangerous for the existence of animals. It was established that the decrease in daily milk yield by 1.3 kg is a consequence of the negative influence of the temperature factor, when the daily air temperature in the summer period was at the level of +24.5-36.4 oС. The proof of this is the decrease in the rate of decline in the level of milk productivity of the cows of the experimental groups in August, when the average daily air temperature dropped to +24-26 °C. Modernization of the feeding ration of high-yielding cows by increasing the content of non-degradable protein in the rumen to the norm during temperature stress contributed to better adaptation of animals to productivity and quality indicators of milk. Keywords: protected protein, cows, milk productivity, protein supplement, heat stress.