The «SmartBiotic» effect on blood phagocytic activity in rainbow trout

Abstract

Nonspecific cellular immunity is the defense line against the effects of environmental factors. Phagocytic activity of blood is an actual and informative parameter to evaluate analyzing the effectiveness of drugs and feed additives in animal and poultry husbandry. Fish farming is no exception – increasing the fish body resistance is an important and urgent task in order to improve and maintain the quality of the products obtained. The most priority aquaculture direction in Leningrad region is the rainbow trout breeding. In this regard, the development and evaluation of means to increase the productivity and resistance of fish is an urgent task for veterinary science. The purpose of the presented study was to evaluate the effect of the complex mineral feed additive “SmartBiotic” on the phagocytic activity in rainbow trout fingerlings. For this purpose, 3 pools were formed – in the first pool, the concentration of the studied additive was 0.15%, in the second pool, the concentration of the studied additive was 0.25%, in the third pool – the control group. Blood sampling was taken three times each month. In the blood, the number of leukocytes and the level of phagocytic activity were evaluated according to generally accepted methods. During the experiment, the beneficial effect of the studied additive on the phagocytic number and phagocytic index of the studied fish was revealed, and the best results were found in individuals contained in a pool with a concentration of 0.25% of the studied additive.