Effect of dietary supplementation of chromium on growth and biochemical parameters of Labeo rohita (Hamilton) fingerlings

Abstract

A 60-day feeding experiment was conducted to evaluate the effect of dietary chromium on growth, feed efficiency and biochemical parameters of Labeo rohita fingerlings. Four isonitogenous (crude protein 35%) and isocaloric (415 k cal 100 g-1) experimental feeds were prepared by supplementing different levels of dietary chromium picolinate viz., control (0.0 mg kg-1), T1 (0.4 mg kg-1), T2 (0.8 mg kg-1) and T3 (1.2 mg kg-1). Weight gain WG (%), specific growth rate (SGR), feed efficiency ratio (FER) and protein efficiency ratio (PER) and apparent net protein utilisation (ANPU %) were significantly improved (p<0.05) when chromium was supplemented at 0.8 mg kg-1 feed. The protein retention (PR %) value increased with the dose of chromium, showing the highest value in T2 group. Chromium supplementation significantly increased (p<0.05) liver glycogen in T1 and T2 groups but decrease was observed at high level of chromium supplementation in T3 group. Chromium supplementation significantly reduced (p<0.05) serum cholesterol and triglycerides in all the experimental groups compared to control showing the highest reduction in T2 group. The serum high density lipoproteins-cholesterol (HDL-C) was increased (p<0.05)in all experimental groups due to chromium supplementation and the highest blood HDL-C was observed in T2 group. However, no difference (p<0.05) in the serum low density lipoproteins-cholesterol (LDL-C) and phospholipid was observed in any of the experimental groups. Similarly, highest muscle protein as well as lowest liver AST and ALT were observed in T2 group. The results of the present study indicates that growth, feed utilisation and biochemical parameters in Labeo rohita can be significantly improved by feeding the fingerlings with chromium picolinate supplemented diet (0.8 mg kg-1feed).