The influence of probiotics of various microbiological compositions on the growth, interior parameters and microflora of the digestive tract of juvenile sterlet (Acipenser ruthenus L. 1758)

The paper presents the results of a production experiment with young sterlet ( Acipenser ruthenus L. 1758) conducted at the fish-breeding enterprise OOO Novaya Akvakultura in the Tyumen Region in a closed water supply system. The aim of the study was to assess the effect of probiotics on the results of growing young sterlet ( Acipenser ruthenus L. 1758). Probiotics of various microbiological compositions were added to the diet of young sterlet in the experimental groups at a rate of 0.5 g per kg of feed. The inclusion of probiotic organisms in the diet ensured an increase in the absolute growth rate of juveniles of the experimental groups by 23.29 and 22.14% compared with the control group, contributed to a decrease in opportunistic microflora in the spiral intestine, which is confirmed by a decrease in CFU/ml of Bacillus mesentericus , Bacillus cereus and the absence of Bacillus mycoides , Acinetobacter calcoaceticus , Citrobacter freundii . The profile of the interior features of the studied groups was within acceptable values. In juveniles of the experimental groups, compared with the control, there was a smaller difference in the intestinal index – 3-8%, gills – 7-8% and gonads – 3-10%.