Effect of Maggot Dietary Protein Level on Growth Performance, Feed Utilization, Survival Rate and Body Composition of Heterobranchus longifilis Larvae Reared in Aquarium

Abstract

Aims: This study is aimed to investigate the effects of maggot crude protein levels (25 %, 30%, 35% and 40%) on growth performance, feed utilization, survival rate and body composition Larvae of Heterobranchus longifilis. Study Design: The experiment was carried out in aquaria (38.5 x 46.5 x 28 cm3), stocking each aquarium with 50 larvae (1larvae/L). Four experimental diets were formulated based on the maggot meal as the main protein source. These diets were formulated at 25, 30, 35 and 40% protein levels with maggot meal and maize flour as the major ingredients. Place and Duration of Study: This study was carried out in the reproduction laboratory, at Oceanological Research Center, Abidjan, Ivory Coast between the periods of March to May 2011. Methodology: The diets were offered to the larvae (initial mean weight 0.004±0,001g) three times per day ad libitum for 49 days. Results: The results showed that the growth indices such as final body weight, weight gain, and specific growth rate increased significantly with increasing maggot protein level to a maximum at 35% of maggot protein showed insignificant decrease in growth indices. Feed conversion ratio and protein efficiency ratio were better in 35% of maggot protein level. The highest values of survival rate were recorded with fish fed 35% and 40% maggot protein. Concerning body composition of larvae moisture and ash were not affected by dietary maggot protein level. The protein content of larvae increased with increasing of dietary protein level while the lipid content decreased. Conclusion: From the present results, diet containing 35% of maggot protein is considered optimal for Heterobranchus longifilis larvae.