Effects of Thermostable Bacterial α-AMYLASE On Growth Feed Utilization In Rohu, Labeo Rohita (Hamilton), Fingerlings

Abstract

The effects of dietary supplementation of thermostable bacterial α-amylase (produced by Bacillus stearothermophilus, a thermophilic soil bacterium) on the growth, feed conversion, body composi- tion and digestive enzyme profile of rohu, Labeo rohita, fingerlings were evaluated. Rohu finger- lings (avg wt 0.99±0.01 g) were fed purified isonitrogenous diets (35% crude protein) with crude bacterial α-amylase at 350, 525, 700 and 850 U per 100 g feed for 60 days at 3% of their body weight. Fingerlings fed the enzyme-supplemented diets performed better than the control group which received no enzyme supplementation. The best performance in terms of percent weight gain, SGR, FCR and PER was achieved in fish fed the diet supplemented with 700 U of α-amylase. The bacterial α-amylase led to higher protein accretion and lipid depletion in the carcass up to the 700 U incorporation level. Intestinal protease and α-amylase activity increased in all groups com- pared to the initial level.