Effects of selenium (Sel-Plex) supplement on blood biochemical parameters of juvenile Siberian sturgeon (Acipenser baerii)

Selenium (Se) and many of its compounds are among the most toxic micronutrients. Therefore, determining the optimal level of selenium in the diet of fish is one of the main concerns of researchers. The present study was designed to investigate the effects of Sel-Plex® (Selenium-enriched Saccharomyces cerevisiae yeast) on blood biochemical parameters in juvenile Siberian sturgeon, Acipenser baerii, as clinical biomarkers to evaluate the effects of selenium on the health of fish. In this study, fish were fed diets supplemented with 0 (control), 5, 10 and 15 g Sel-Plex per Kg feed for 8 weeks. Although a significant (p<0.05) decrease was observed in alkaline phosphatase (ALP) and gamma-glutamyl transferase (GGT) activity in fish fed with 15 g Sel-Plex supplement, plasma aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities were significantly higher (p<0.05) than the control fish. The results showed that administration of 10 and 15 g Sel-Plex supplement in fish significantly (p<0.05) increased lactate dehydrogenase (LDH) and creatine phosphokinase (CPK) activities. Administration of Sel-Plex significantly (p<0.05) decreased glucose, albumin, cholesterol and triglyceride concentrations. The results revealed that Sel-Plex significantly increased (p<0.05) globulin concentrations in the supplemented groups compared with the control group. Decreased total protein concentrations were only observed in fish fed with 5 g Sel-Plex. The results of this study show that diets containing high concentrations of Sel-Plex (10 g and 15 g) produced serious toxic effects, including changes in blood biochemical parameters.