INFLUENCE OF TECHNOLOGICAL STRESS ON NON-SPECIFIC RESISTANCE OF THE ORGANISM OF COWS

Abstract

Background. The intensification of animal husbandry leads to a violation of the adaptive capabilities of the body, a decrease in productivity and natural resistance of animals. The study of nonspecific factors of protection of the cow's body will allow us to develop ways to increase the immune status and as additional information can be used in breeding work for the selection of highly resistant parent pairs. Purpose. The study of the cellular and humoral link of nonspecific resistance in the development of a stress reaction in cattle after the action of technological stress on the body of cows. Materials and methods. The work was carried out on 20 clinically healthy highly productive black-and-white cows. The stressor for the cows was the regrouping, the change of attendants, the conduct of veterinary and sanitary manipulations. The total number of leukocytes, leukogram, bactericidal and lysozyme activity of the blood serum of cows were studied by standard clinical and laboratory methods and the morphology of leukocytes on a scanning electron microscope before and 3, 14, 30 days after technological stress. Results. On days 3-14 after stress, leukocytosis, neutrophilia, monocytosis and lymphopenia were detected relative to the initial level. When using high-resolution microscopy using a scanning electron microscope, the appearance of NEToses in the blood of cows after technological stress was detected. A decrease in the bactericidal activity of serum on the 3rd day after stress with its subsequent increase was established, on the contrary, an increase in lysozyme on the 3rd day was accompanied by its subsequent decrease by 30 days after the technological stress relative to the initial level. Conclusion. The data obtained indicate that the body's defenses are a dynamic physiological indicator, which must be considered as a general resistance of the cattle body to stressors in order to prevent the disruption of the body's adaptive capabilities.