Liver condition and blood biochemical value of sturgeon fish when fed combined feed with increased fat content.

The results of the present experiment revealed that by feeding feed with a high fat content, the final weight of fish increases by 10.0-23.9%, feed cost per kg of weight gain is reduced by 14.4-28.7%. The condition factor of juvenile Russian-Lena sturgeon (hybrid of Acipenser baeri and Acipenser gueldenstaedtii) increases by 12.6-31.6%. With an increase in the percentage of feeding fat-rich feed, an increase in liver mass indices by 13.9-17.8%, spleen mass indices by 13.0%, a decrease in intestinal mass indices in fish of the third and fourth groups -by 15.4 and 17.1%, and stomach of juveniles -by 7.4 and 9.0%. An increase in the severity of fatty hepatosis associated with a certain level of feeding affected the carbohydrate metabolism of fish. In the experimental groups (with a fat content of 15.8-20.0% in compound feed), there is a higher glucose content in relation to the control group (with a fat content of 14% in compound feed), with a difference of 12.7-13.5%. The biochemical picture indicates the liver damage in the fish of the experimental groups, while during the transition to a more pronounced stage, the cholesterol concentration falls below normal. An increase in AST activity was -by 14.0-60.7%, relative to the control. In the level of ALT, an increase in the indicator was recorded only in the second and third experimental groups with a difference of 12.1% and 14.1%, respectively, and in the fourth experimental group, on the contrary, the content of this enzyme was lower by 29.4% relative to the control group. Considering the significant degree of liver damage in fish of this group, this can be explained by the fact that the peak of destruction of hepatocytes has already passed, and then the level of aminotransferases becomes minimal.