Replacement of fishmeal by fermented silkworm pupae meal in diets of largemouth bass (Micropterus salmoides): Effects on growth performance and feed utilization

The present study was conducted to evaluate the effects of graded replacing fishmeal with fermented silkworm pupae meal (FSPM) on the growth, feed utilization and body index of largemouth bass (Micropterus salmoides). The control diet (FSPM0) was produced using fishmeal as the main protein source and the other five diets were formulated by replacement of 10% (FSPM10), 20% (FSPM20), 30% (FSPM30), 40% (FSPM40) and 50% (FSPM50) fishmeal with FSPM. Six groups containing 540 largemouth bass (36.17 +/- 0.71 g) were fed to apparent satiation for 10 weeks. The results indicated the weight gain rate, specific growth rate, feed efficiency rate, protein efficiency rate of fish in FSPM30 group were significantly higher than those in other groups. However, the feed intake of fish in FSPM30 group was significantly lower than those in other groups. No significantly changes for hepatosomatic index of fish were observed in all groups. Polynomial regression analysis indicated that the optimal ratio of replacement fishmeal by FSPM was 27%. In conclusion, FSPM can be included into the diet of largemouth bass replacing 27%-30% of fishmeal without negative effect on growth, feed utilization and body index.