Supplementation of Siberian sturgeon (Acipenser baerii) diet with barberry (Berberis vulgaris) fruit extract: Growth performance, hemato-biochemical parameters, digestive enzyme activity, and growth-related gene expression

Abstract

In this study, barberry fruit extract (BFE) was used as an herbal feed additive at 0 (control), 150, 300, 600, and 750 mg/kg to evaluate growth performance, physiometabolic responses, and gene expression related to growth and appetite in Siberian sturgeon. The fish (N = 150; 29.7 ± 2.2 g) were fed with the experimental diets for 56 days. Upon the completion of the feeding trial, the fish fed with BFE at 750 mg/kg showed higher growth indices than the control fish and the lowest feed conversion ratio (P < 0.05). The highest levels of red blood cell, hemoglobin, and hematocrit were observed in the group fed with 750 mg/kg BFE (P < 0.05). Different dietary levels of BFE had no significant effect on the levels of alkaline phosphatase and alanine aminotransferase in the serum samples (P > 0.05), while a decreasing trend was seen in aspartate aminotransferase, lactate dehydrogenase, glucose, and triglyceride contents by increasing in the dietary levels of BFE. The activities of lipase, amylase, and protease in the BFE-added groups were higher than the control group (P < 0.05). The highest expression of growth hormone gene was recorded in 600 and 750 mg/kg BFE treatments (P < 0.05). The transcription of insulin-like growth factor-I gene was significantly up-regulated in 750 mg/kg BFE treatment compared to others (P < 0.05). Ghrelin gene expression was significantly elevated in both brain and stomach tissue samples by increasing dietary levels of BFE. Overall, dietary BFE markedly at 750 mg/kg exerts growth-promoting effects in Siberian sturgeon.