Effects of dietary onion (Allium cepa) powder on growth, innate immune response and hemato-biochemical parameters of beluga (Huso huso Linnaeus, 1754) juvenile

The present study was aimed at determining the effects of dietary onion powder on growth, innate immune response and hemato-biochemical parameters of beluga juvenile (Huso huso). Basal diets containing onion powder 0 (control), 0.5 and 1% of feed were fed to beluga juvenile. At the end of the experiment, the highest weight gain (WG%) and specific growth rate (SGR) was observed in group fed with 1% onion (P < 0.05). There were no significant difference (P > 0.05) about feed conversion ratio (FCR) in treatment groups that fed diets containing various levels of onion powder. After 8 weeks, serum lysozyme activity, superoxide dismutase activity (SOD), respiratory burst activity and serum total immunoglobulin (Ig) showed a significant increase in treatment group with 1% onion powder compared to other groups (P < 0.05). The group fed 1% onion showed a significantly increases in the number of erythrocytes (RBC), leucocyte (WBC), haematocrit (Hct) levels compared to the control group (P < 0.05). Haemoglobin, monocyte, lymphocyte and neutrophil had no significant change (P > 0.05) in treatment groups and control. The analysis of AST and LDH levels showed a significant decrease in 1% onion compared to the control and 0.5% onion diet (P < 0.05), while ALT and ALP levels were not influenced (P> 0.05). The blood glucose, total protein, triglyceride, cholesterol, albumin and globulin levels were lower in treated groups compared with the control (P < 0.05). The results of this study demonstrated that dietary onion powder could be an improvement in growth, hematological parameters and immune function of beluga juvenile. (C) 2015 Elsevier Ltd. All rights reserved.