Growth performance, health status, gut microbiome, and expression of immune and growth-related genes of rainbow trout (Oncorhynchus mykiss) fed diets with pea protein replacement of fish meal

Comp Biochem Physiol B Biochem Mol Biol. 2024 Apr 9;273:110968. doi: 10.1016/j.cbpb.2024.110968. Online ahead of print.ABSTRACTThe need for fish meal constrains fish farming and significantly impacts sustainability of the aquaculture industry. Hence, it is important to investigate the use of plant-based protein sources in fish diets. The present study was conducted to determine the effects of different levels of fish meal (FM) replacement by pea protein (PP) in a 60-day feeding experiment in rainbow trout, Oncorhynchus mykiss. Effects on growth performance, body composition, hematology, serum biochemistry and immunology, and immune (TNF-α, IL1-ß and Il-8) and growth-related (GH and IGFI) gene expression were investigated. Five experimental diets (45% protein and 20% lipid) differed in replacement level of FM by PP at rates of 0% (control (PP0)), 25% (PP25), 50%(PP50), 75%(PP75) and 100%(PP100). Fish were fed with experimental diets in triplicate twice daily. The best growth performance was obtained in PP0 and PP25 groups. While fat ratios of fish fillets significantly differed (p < 0.05), there was no significant effects on protein ratios (p < 0.05). There was no significant change in the hematological values of fish, except those fed the PP100 diets, which displayed a reduction in eyrthocyte counts, hemoglobin content and hematocrit. As PP supplementation increased fish showed elevated serum glucose, total protein, cholesterol and myeloperoxidase activity and decreas...
Source: Comparative biochemistry and physiology. Part B, Biochemistry and molecular biology. - Category: Biochemistry Authors: Source Type: research