Effects of the Replacement of Fish Meal with Cricket Meal on Growth, Muscle Amino Acid Composition, and Serum Biochemical Indices of Juvenile Yellow Catfish (Pelteobagrus fulvidraco)

Abstract

In recent years, with the increase of varieties and the expansion of scale in aquaculture, as well as the rapid development of the intensive and industrial aquaculture industry, the demand for fish meal has increased significantly. On the other hand, due to global warming and environmental pollution, marine resources have reduced and the production of high-quality fish meal is gradually decreasing. The soaring prices of fish meal increase the feed cost in the process of aquaculture, severely decrease the economic benefits of aquaculture farmers, greatly limit the use of fish meal in aquatic feed, and hinder the sustainable development of the aquaculture industry. Therefore, it has become an important research subject in the aquatic feed industry to find new fish meal substitutes and reasonably reduce the amount of fish meal in feed. Crickets have high nutrient concentrations (55%–73% crude protein, high unsaturated fatty acid levels, and sufficient essential amino acid (EAA) profiles). For cricket meal, as one of the new high-quality insect protein sources, the crude protein concentration is comparable to that of fish meal. Recent studies have shown that cricket meal can replace part of fish meal, and have achieved good results in Clarias gariepinus, Micropterus salmoides, and other aquatic animals. However, the application of cricket meal as a substitute for fish meal in the diets of yellow catfish has not been reported. In the present study, we investigated the effects on the growth performance, muscle composition, and serum biochemical indexes of yellow catfish by replacing different proportions of fish meal in the diets with cricket meal. The aim was to explore the feasibility of replacing fish meal in the diets of yellow catfish, and to provide a scientific reference for the future development and application of insect protein sources in aquatic feed. The cricket meal used in this study was a brown powder containing dry matter crude protein content of 63.40%, crude fat content of 15.50%, and crude ash content of 7.36%. Healthy juvenile yellow catfish with an average body weight of (2.0±0.13) g were randomly divided into five groups with three replicates and 30 fish per replicate. Five isonitrogenous and isoenergetic experimental diets were formulated by replacing 0%, 15%, 30%, 45%, and 60% of fish meal protein with cricket meal, named T0, T15, T30, T45, and T60 groups, respectively. The experimental fish were reared in an indoor recirculating aquaculture system for 10 weeks. By measuring growth performance, muscle amino acid content, and serum biochemical parameters, the appropriate replacement level of cricket meal in yellow catfish diets was investigated.The results showed that with increasing cricket meal content, the final body weight (FBW), weight gain rate (WGR), and specific growth rate (SGR) of juvenile yellow catfish increased first and then decreased. The growth performance of FBW, WGR, and SGR in the T30 group was the highest and significantly higher than that of FBW, WGR, and SGR in the T0 group (P 0.05). The EAA contents of the muscle arginine and valine in the T60 group were significantly higher than those in the T0 group (P0.05). Compared with the T0 group, the content of glucose (GLU) in the serum of the T30, T45, and T60 groups significantly increased (P<0.05), whereas the content of total cholesterol (TCHO) was significantly decreased (P<0.05). The activities of the serum superoxide dismutase and catalase in the T30 and T60 groups were significantly higher than those of the T0 group (P<0.05). In conclusion, under our experimental conditions, the growth performance and muscle amino acid composition of juvenile yellow catfish were not affected by replacing fish meal with cricket meal, and serum biochemical parameters and TCHO contents were increased. The optimal growth rate was achieved by replacing fish meal with 30% cricket meal. The results of indicate that cricket meal is an excellent substitute for fish meal and provides a theoretical reference for the application of cricket meal as a partial substitute for fish meal in aquatic animal diets.

Keywords

• pelteobagrus fulvidraco
• cricket meal
• growth performance
• muscle composition
• serum biochemical indices