The dissertation is devoted to the study of the immunological potential of the body of young cattle under conditions of cadmium loading and the action of corrective factors. The conducted research made it possible to study in more depth the effect of Cadmium on the body of animals and to make appropriate additions to the disclosure of the mechanisms of chronic toxicosis in animals, taking into account the state of the immune system.
Comprehensive assessment of morphological and biochemical parameters of animal blood, protective systems of the body allows to comprehensively assess the degree of damage to the body of young cattle with Cadmium and choose ways to correct the immune system in the presence of animal feed toxicant in quantities exceeding the daily allowance. In the blood of bulls with experimental chronic cadmium toxicosis, a probable decrease in the number of erythrocytes by 18.4 %, hemoglobin level – by 14.1 %, hematocrit – by 12.1 %, as well as an increase in the number of leukocytes by 11.9 %. In sick animals, a violation of the protein-synthesizing function of the liver and liver function. In addition, a decrease in the activity of cytochrome oxidase and succinate dehydrogenase as marker enzymes used to assess energy metabolism and the course of hypoxia in animals with various negative factors. With the development of chronic cadmium toxicosis in bulls suppressed their antioxidant status, which reduces the enzyme link and non-enzymatic link of the antioxidant defense system. Feeding bulls with cadmium chloride feed at a dose of 0.04 m/kg body weight contributed to the suppression of the immune system, as indicated by a decrease in cellular, humoral and nonspecific immunity in bulls under cadmium load. A new liposomal drug «Lipointersyl», made on the basis of interferon and milk thistle, has been developed. For the first time, its pharmaco-toxicological evaluation was performed on laboratory animals and young cattle. In determining the parameters of acute toxicity in laboratory animals, the liposomal drug «Lipointersyl» belongs to the IV class of toxicity, namely to low-toxic compounds. The DL50 of the liposomal drug by intragastric and intramuscular administration to white rats is 5166.66 and 5833.33 mg/kg body weight, respectively. When establishing the subacute toxicity of the drug «Lipointersyl» it was found that the administration to experimental animals of this drug in doses of 1/50 and 1/100 DL50 for 28 days does not cause visible clinical signs of intoxication, and the studied hematological and biochemical parameters do not exceed the control animals. Based on the results of our experimental studies, it can be argued that the feed additive «Metisevit» and liposomal drug «Lipointersyl» in chronic cadmium toxicosis of bulls, normalize the morphological and biochemical parameters of the blood. The use of the feed additive Metisevit and the liposomal drug Lipointersyl in bulls under cadmium loading led to an improvement in protein metabolism, including an increase in total protein. When feeding the feed additive «Metisevit» and the use of liposomal drug «Lipointersyl» in young cattle, under conditions of cadmium loading, the activity of AST and ALT in the serum of experimental bulls decreased. The use of the feed additive Metisevit and the liposomal drug Lipointersyl in bulls under cadmium load helped to increase the antioxidant status of their body throughout the experiment, as indicated by increased activity of glutathione peroxidase, glutathione reductases, glucose-6-phosphide. The use of liposomal drug «Lipointersyl» contributed to a more likely increase in the activity of enzymes of the glutathione system of antioxidant protection due to milk thistle, which is part of this drug. Feeding Metisevit feed to bulls under a cadmium load helped to increase their immune status. Namely, it had a positive effect on the stimulation of T- and B-cell immunity in animals and increase the body's ability to actively synthesize protective antibodies. In the study of the phagocytic index in bulls fed a feed additive and used a liposomal preparation, an increase in the blood of bulls in both experimental groups was found starting from the 10th day of the experiment. The positive effect of the use of feed additive «Metisevit» and liposomal drug «Lipointersyl» was found on the humoral part of the immunity of bulls under cadmium loading. Additional use of the liposomal drug «Lipointersyl» in bulls under cadmium load contributed to a more likely increase in antioxidant and immune systems compared to bulls, which were fed only a feed additive «Metisevit».
