In the conditions of the milk production complex in the Voronezh region, where Holstein cattle are kept, studies were conducted to study the degree of injury to blood cells during its selection by various methods in healthy calves and with endogenous intoxication syndrome. In healthy animals, blood sampling by passive leakage does not affect the membranes of erythrocytes. When using vacuum systems, there are no visual signs (hemolysis) of cell destruction, but changes in their cytoskeleton occur with an increase in the sensitivity of membranes to negative pre-analytical factors. In animals with endogenous intoxication syndrome, there are explicit or hidden destruction of erythrocyte membranes, which are manifested by an increase in the content of extra-erythrocyte hemoglobin, the degree of physiological hemolysis, sensitivity to intra- and extravascular hemolytic factors. As a result, already when selecting blood samples by passive gravity, there is a risk of hemolysis, and when using a vacuum system, it is observed in most samples. Therefore, when examining sick animals, it is necessary to take into account the high probability of laboratory diagnostic error at the pre-analytical stage that occurs due to hemolysis of erythrocytes with hypersensitivity to extravascular cytolytic factors, including mechanical effects during blood sampling.

The relevance of this study is due to the need to assess the functioning of the cellular component of the immune system in dynamics in sows before insemination, during periods of gestation and lactation in the norm and in the event of postpartum pathology.The purpose of the research is to study cellular immunity in sows in different physiological conditions. The article presents the results of a study of cellular immunity in sows before insemination, during periods of gestation and lactation in normal and postpartum pathology in an industrial pigbreeding complex. Cellular immunity indicators were determined in the blood: T- and Blymphocytes, theophylline-resistant (Ttfr), theophylline-sensitive (Ttfh) lymphocytes and their ratio (Ttfr/Ttfh) in accordance with the "Methodological recommendations for assessing and correcting the immune status of animals" .Statistical processing of the obtained data was carried out using the program Statistica v6.1, reliability assessment - Student's test. It has been established that before insemination, diseased animals have reduced cellular adaptive immunity compared to clinically healthy sows. With the onset of gestation (37-39 days), sows of both groups showed suppression of cellular immunity, which is necessary to ensure the tolerance of the mother's body to fetal alloantigens, the normal course of pregnancy and fetal development, which was more significant in diseased animals. In the second half of gestation (78-80 days), the marked increase in cellular adaptive immunity in sows of both groups is associated with the effect of antigens of the administered vaccines, which was more pronounced in clinically healthy animals. During lactation, the cellular immune response to the administered vaccines in diseased sows was also less significant.

The article presents the results of studying the formation of specific immunity in piglets during vaccination against circovirus infection. Circovirus diseases of pigs, manifested by the defeat of many body systems, are widespread and cause great economic damage in industrial pig farms. The study of the formation of specific immunity during vaccination of piglets against circovirus infection is of scientific and practical interest. The purpose of the research is to study the formation of specific immunity in piglets during vaccination against circovirus infection. It was found that vaccination is accompanied by activation of the innate immunity system, which initiated the launch and formation of an antigen-specific adaptive immune response. In animals 6 days after the introduction of the vaccine, compared with intact piglets, an increase in the content of pro-inflammatory cytokines IL-1ß, TNF-α, IFN-α and IFN-γ and the anti-inflammatory mediator IL-4 was found, indicating a cellular and humoral immune response. An increase in the indices of inflammatory activity of mediators and the ratio of pro- and anti-inflammatory cytokines indicates an increase in the activity of T-helper I and the prevalence of cellular immune response. Under the influence of technological stress caused by weaning from sows and transfer to rearing, animals 14 days after vaccination showed a decrease in the level of IL-2, IFN-α and IFN-γ, inducing cellular immunity, as well as cytokine index, the ratio of pro- and anti-inflammatory mediators, which indicates a shift in the direction of the immune response in the side of activation of the functioning of T-helper II, indicating the predominant formation of humoral immunity.

ФГБНУ «Всероссийский научно-исследовательский ветеринарный институт патологии, фармакологии и терапии»