The effects of partial replacement of fishmeal with hermetia meal on the growth and fatty acid profile of African catfish fry

Abstract

Fishmeal is becoming an increasingly expensive resource. Therefore, it is important to find other sources of protein to reduce feed costs. The larvae of the black soldier fly, Hermetia illucens, was evaluated as an alternative protein source for the African catfish, Clarias gariepinus, in six-week feeding trials. Three experimental diets were iso-nitrogenous (35% crude protein) and iso-lipidic (18 % crude fat). The following ratios of fish meal were used in the study: 1 fish meal (FM, control); 1:2 hermetia meal to fish meal (1HM:2FM); and 1:1 hermetia meal to fish meal (1HM: 1 FM). Two hundred and seventy catfish fingerlings (mean initial weight: 2.45 g) were distributed to nine tanks corresponding to three treatments with three replicates. The experiment examined weight gain, specific growth rate (SGR), feed conversion ratio (FCR) and muscular body composition as growth parameters. The study found that substitution of one-third of fish meal protein with hermetia meal had no negative effect on the growth performance of African catfish fry fed 1HM:2FM, which showed greater weight gain (17.74 ± 0.722g). The muscle composition of fish fed 1H:1FM showed a significant proportion of protein between diets. The fatty acid profile of fish muscle reflected the content of the diet. Based on the results, it was concluded that the protein meal of the black soldier fly can serve as a substitute for the diet of the African catfish.