Abstract

Lemon peel is by-products contain bioactive compounds that has beneficial effects on fish health. A 45-day feeding trial was conducted to evaluate the potential of dietary dehydrated lemon peel (Citrus limon) powder (DLPP) on metabolic enzyme, serum components and stress status of rainbow trout juvenile (initial weight of 26.8±1.9 g). Fish were randomly stocked to four treatments feeding diets containing 0 (control), 0.5, 1.5, and 2.5% of DLPP diets in triplicates. At the end of feeding experiment, metabolic enzyme (Alkaline phosphatase; ALP, Aalanine transaminase; ALT, Aspartate aminotransferase; AST), serum biochemistry (cholesterol, triglyceride, protein and albumin) and stress (glucose and cortisol) were assessed. There was no significant difference in fish growth performance between treatments (p>0.05). Fish fed with 1.5% of DLPP showed a significant decrease in cholesterol and triglyceride (p<0.05). Moreover, serum protein and albumin were improved in fish fed with 1.5% and 0.5% DLPPP, respectively (p<0.05). The highest of AST, ALP and ALT were observed in control group (p<0.05). There were no significant differences in cortisol and glucose of fish between the treatments (p>0.05). Finally, it seems that the inclusion of 0.5 and 1.5% DLPP in diet can improve metabolic enzymes, biochemical parameters and reduced stress of rainbow trout juvenile.

Keywords: Lemon peel, Hepatic enzyme, Biochemical parameters, Stress, Rainbow trout