Economic Evaluation of Different Culture Enclosures for Musca domestica Larval Production and Their Utilization for Clarias gariepinus (Burchell, 1822) Fingerlings Diets

Abstract

The study was designed to investigate the rate of larval (maggot) production from different culture enclosures, as well as to compare the cost effectiveness and utilization of the maggot in the diet of African mud catfish, Clarias gariepinus. Musca domestica larvae were cultured from poultry dung for five week, where upon they were utilized as a replacement for fish meal in the diet of fingerlings of African mud catfish. The maggots were cultured in four different enclosures: aluminium mobile maggotry, aluminium, plastic and wooden boxes. The harvested maggots were processed by oven drying and powdered as maggot meal. The maggot meal was used to substitute fish meal in eight diets with different inclusion levels of 0% (control), 20%, 30%, 40%, 50%, 60%, 70% and 80%. The formulated diets were fed to C. gariepinus fingerlings in triplicates for 10 weeks. The growth, nutrient utilization and survival of fish were monitored during the experimental period. The cost effectiveness of different culture enclosure was studied. Results indicate that aluminium box was the best option, giving the highest weight of maggot production, and was the most cost effective of all the culture enclosures studied. Significant differences (p < 0.05) were recorded in weight gain of fish between the control and the maggot meal-based diets, while the highest weight gain was observed in fish fed 70% maggot meal-based diet. Specific and relative growth rates were found to be high in fish fed 60% maggot meal diet, while they were lowest in fish fed 20% maggot meal diet and the control diet. The best protein intake was recorded in fish fed the 70% maggot meal-based diet and lowest in fish fed the control diet. Survival of fish was generally high (78.3%-93.30%) and was significantly (p < 0.05) different between the fish fed as the control and the maggot meal-based diets. The study confirms that maggots of Musca domestica are suitable as partial replacement of fishmeal at 60-70% inclusion level for optimal growth performance and nutrient utilization in Clarias gariepinus fingerlings.