The conduct of industrial pig breeding involves technological stresses that cause adaptive changes in the body, requiring additional energy consumption, which negatively affects the productivity of animals. By influencing the formation of the bodys adaptive reactions with biologically active substances, it is possible to reorient metabolic processes towards anabolism. It is known that the use of biologically active substances optimizes homeostasis, but the modes of their use require clarification. In order to study the influence of the scheme of feeding the feed additive Yeast hydrolysate Protamin on the homeostasis of pigs in different periods after the introduction of antigens and against the background of pre-slaughter manipulations were formed 3 groups of piglets of 10 heads of 58-61 days of age with a live weight of 11.16 ± 0.01kg. Animals of group 1 were control, piglets of group 2 received 5 grams of feed supplement Yeast hydrolyzate Protamin with water once a day (individually using a feed injector) for 2 months according to the following scheme: 7 days - drinking, 7 days - a break; animals of group 3 received the same amount of supplements, but according to the scheme: 7 days - drinking, 14 days - a break. The hemogram indices of the experimental animals were determined using the Abacus junior vet 5 hemanalyzer. Biochemical parameters of blood serum were determined at the testing center of the Federal State Budgetary Educational Institution Bryansk Interregional Veterinary Laboratory according to generally accepted methods. The animals were weighed individually. It was found that the feeding of the feed additive Protamin to pigs for 2 months according to both schemes led to a high level of anabolism in a month after the end of drinking the drug, more pronounced in pigs receiving the drug according to the scheme: 7 days - drinking, 7 days - a break. They have a higher level of energy metabolism. The use of this scheme of feeding the additive promoted the formation of a calm activation reaction in animals in the absence of stress factors and the optimization of homeostasis, and under conditions of pre-slaughter manipulations - a reaction of increased activation, caused an increase in the level of reactivity of the organism in pigs and provided a significant increase in live weight by 13.57 and 22.70% respectively. Output. For the formation of adaptive reactions in pigs, ensuring the optimization of homeostasis and an increase in live weight, the most effective scheme for the feeding of the feed additive Yeast hydrolysate Protamin: 7 days - drinking, 7 days - a break.
Key words: Feed additive; Morphological and biochemical blood parameters; live weight. Pigs.