Silkworm caterpillar - soybean meal blend as dietary protein source in the practical diets of Heterobranchus bidorsalis fingerlings

Abstract

An experiment was conducted to evaluate the utilization of silkworm caterpillar meat (SCM) blended with soybean meal (SBM) as a dietary protein source in the practical diet of Heterobranchus bidorsalis fingerlings (M±SE=17.04±_0.02g). The fish were fed five isonitrogenous and isocaloric diets containing blends of SCM and SBM in ratios of 25:75, 50:50, 75:25, and reference diets containing 100:00 and 00:100 of SCM and SBM respectively for 8 weeks at 4% body weight per day. A trend of difference in nutrient utilization was observed as Diet 4 (100SCM:00SBM) recorded mean weight gain (MWG) of 35.39g and better specific growth rate, food conversion ratio and protein efficiency ratio than any other diet. This was followed by Diet 3 (75SCM:25SBM) which gave MWG value of 28.71g. There was marked significant difference (P<0.05) in the MWG values among fishes fed the five diets. Also there was observed significant difference (P<0.05) in the ash, lipid and crude protein of the carcass of the experimental diets.

Key words: Silkworm, Soybean meal, Heterobranchus bidorsalis.