Abstract
The aim of research is to study the influence of zoohygienic parameters of the microclimate of livestock buildings on milk productivity and milk quality. The identification of the trend in changes in milk productivity in the winter-spring period depending on the microclimate and zones of location of highly productive animals was carried out in the North Kazakhstan Region on the basis of one of the dairy farms. Experimental studies were carried out according to the traditional methodology of planning experiments by forming experimental groups using laboratory, instrumental and statistical research methods. The object of the study is Simmental cows. The material of the study is milk of the animals under study. For the study, 3 groups of animals were selected and formed according to the principle of pairs-analogues of the second calving, 20 heads in each group. Group I – the animals were located in the southern zone of the complex; Group II – in the central zone and Group III – in the northern zone. A trend was revealed in milk productivity and physicochemical parameters of milk depending on climatic changes in the season and microclimate parameters. The trend in changes is associated with temperature changes in the winter, when animals spent a lot of energy on heat exchange and could not fully produce milk. Milk productivity decreased in the winter by 10 % compared to the spring. The dynamics between the periods differed significantly in fat content: animals of Group I in the spring had an average fat content of (4.10 ± 0.20) %, in the winter the indicator was (3.81 ± 0.12) % and was 7.1 % less; in the second group – (3.89 ± 0.15) and (3.75 ± 0.18) %, respectively, and the difference was 3.59 %, and in the third group – (3.29 ± 0.17) and (3.51 ± 0.09) %, and the difference between periods was 2.3 %, respectively. Decreasing and increasing temperature, increasing and decreasing humidity, increasing harmful gases, dust pollution in livestock buildings also contribute to a decrease in milk productivity of cows.