Effect of a Probiotic Supplement on Growth, Nutrient Utilisation and Carcass Composition in Mrigal Fry

Abstract

Four isocaloric and isonitrogenous diets, D-1, D-2, D-3 and D4, were prepared with supplementation of Bioboost Forte (a probiotic supplement manufactured by Lyka Labs Ltd., Bombay) at 0, 100, 150 and 200 mg/kg. respectively, for feeding mrigal (Cirrhinus mrigala) fry (mean initial body weight-0.65 g) in a laboratory trial of 63 days' duration. The feeds were prepared using locally available ingredients - groundnut oil cake, rice polish, roasted soybeanmeal, fishmeal, and vitamin and mineral premix at appropriate levels. The diet D-3 exhibited the best performance in terms of both growth and nutrient utilisation with a significantly higher growth of 13.90 ± 0.87 g/IO fry, lower feed conversion ratio of 2.27 ± 0.21, higher specific growth rate of 1.87 ± 0.09 nd higher protein efficiency ratio of 1.26 ± 0.12. The final carcass composition of fish fed D-3 diet showed higher protein and lipid contents than those fed on the other three diets, and the initial carcass protein and lipid levels. No disease or mortality occured during the experimental period. The results indicated that the probiotic supplement at 0.15% showed significantly higher growth and nutrient utilisation.