SeNPs-probiotic compound treatment for multidimensional regulation of growth, muscle flavor, and nutritional quality in crayfish.

An elemental selenium nanoparticles (SeNPs)-producing Lactobacillus plantarum LP3 strain was isolated and evaluated for effects on Procambarus clarkii (crayfish) growth and muscle quality. Compared with other groups, co-feeding LP3 + SeNPs (1.5 mg/kg) increased the final body weight (20-30 g) and body length (8-10 cm) of crayfish, enhanced muscle elasticity, reduced hardness. It enhanced muscle and hepatopancreas antioxidant capacity, notably GPx. Selenium deposition reached 150 μg/kg in muscle and exceeded 600 μg/kg in the hepatopancreas. Untargeted metabolomics revealed decreased long-chain fatty acids, elevated bile acids and promoted the accumulation of flavor peptides, which correlated with improved growth. Electronic tongue evaluation and free amino acid (FAA) analysis revealed that the combined treatment significantly improved the overall flavor profile and the accumulation of FAA in muscle. A higher dose of SeNPs (2.5 mg/kg) induced oxidative toxicity. Therefore, LP3 + SeNPs (1.5 mg/kg) effectively improves crayfish growth, muscle quality, and flavor, providing a promising strategy for aquaculture.