Physiological Response of Grower African Catfish to Dietary Black Soldier Fly and Mealworm Meal

Abstract

A six-week experiment was carried out to test the effects of total (100%) and partial (50%) replacement of fish meal in the diet of African catfish growers with black soldier fly (B) meal, yellow mealworm (M) meal, and a 1:1 combination of both (BM) on the production and health of fish. A total of 420 fish with an average initial body weight of 200 ± 0.5 g were randomly distributed in triplicate to seven diet groups (C, B50, B100, M50, M100, BM50, and BM100, respectively). The growth performance and feed utilization of fish fed with partial or total replacement levels of FM with B were not significantly affected (p > 0.05) during the 6 weeks of feeding. In contrast, significant differences were observed between the groups fed with a diet where FM was totally replaced with M meal and the control in terms of final body weight, specific growth rate, feed conversion ratio, protein efficiency ratio, and protein productive value. Among the blood plasma biochemistry parameters, total cholesterol exhibited a significant difference (p = 0.007) between the M treatments and the control diet. The fatty acid profile of the liver was changed with respect to the long-chain polyunsaturated fatty acid content in all experimental groups. Parallel with this, the upregulation of elovl5 and fas genes in liver was found in all experimental groups compared to the control. Overall, this study shows that fish meal cannot be substituted with yellow mealworm meal in the practical diet of African catfish without compromising the growth, health and feed utilization parameters.

Black Soldier Fly (Hermetia illucens) Meal as Direct Replacement of Complex Fish Feed for Rainbow Trout (Oncorhynchus mykiss) and African Catfish (Clarias gariepinus)

“…The use of insects in fish feed is a widely researched topic, but in general, limited to and typically focused only on the replacement of fishmeal [8]. Even there, it is typically used to replace only part of the fishmeal, representing 5-35% of the total feed [22][23][24][25][26][27][32][33][34][35][36][37][38][39]. This is particularly interesting in light of the fact that some fish species consume significant amounts of insects throughout their life cycle, such as African catfish [47][48][49] and especially rainbow trout [42,[50][51][52].…”

“…These experiments have typically yielded positive results: BSF can be incorporated into the diet of African catfish to a greater or lesser amount, but with success. Up to 25-50% of fishmeal in complete feed does not cause production disadvantage, but above this level, usually, problems occur [22][23][24][25][26][27] Table 1. Studies have been carried out on the direct use of different insects in the feeding of African catfish, but these have typically yielded results that are difficult to compare or incomplete [28][29][30], so these are not presented in detail here.…”

Chemical and Physical Properties of African Catfish (Clarias gariepinus) Fillet Following Prolonged Feeding with Insect Meal-Based Diets

“…There are similar findings where BS and MW-containing diets were applied at different inclusion levels with species like Jian carp ( Cyprinus Carpio var. Jian) [ 24 ], rainbow trout ( Oncorhynchus mykiss ) [ 25 ], common carp ( Cyprinus carpio ) [ 26 , 27 ], African catfish [ 28 , 29 ], and Siberian sturgeon ( Acipenser baerii ) [ 30 ]. However, in most cases, juvenile fish is the targeted age category for such nutritional trials.…”

Effects of Dietary Plant Protein Replacement with Insect and Poultry By-Product Meals on the Liver Health and Serum Metabolites of Sea Bream (Sparus aurata) and Sea Bass (Dicentrarchus labrax)

“…To date, many studies have examined the replacement of fish meal with poultry by-products and insect meals in various fish species [23][24][25][26]. For Gilthead sea bream, Sparus aurata, and European sea bass, Dicentrarchus labrax, the results obtained thus far have provided broad support for the utilization of both alternative protein sources as valid substitutes for fish meal to develop sustainable aquafeeds [27][28][29][30][31][32][33][34][35][36][37][38][39][40][41].…”