Abstract

Simple SummaryIn aquaculture, dietary supplement feed with a functional additive is an effective approach to enhancing fish health. Squalene, recognized for its diverse biological activities, has found extensive application in the food and pharmaceutical sectors. This study aimed to evaluate the effects of dietary squalene supplementation on the growth performance and health status of largemouth bass (Micropterus salmoides). The results demonstrated that adding squalene to the diet of largemouth bass can improve growth performance, increase serum total protein level, decrease serum glucose concentrations, and enhance digestive enzyme activity. It enhanced hypoxia tolerance, modulated immune gene expression, and improved the survival rate of largemouth bass against largemouth bass ranavirus (LMBRaV) infection. The optimal dietary supplementation level of squalene for improving growth performance and disease resistance in largemouth bass was determined to be 100 mg/kg of diet. These findings highlight the potential of squalene as a valuable dietary supplement for aquaculture.Feed supplements play a crucial role in improving and maintaining fish health in modern aquaculture practices. Squalene is a functional lipid naturally present in fatty tissues, possessing numerous beneficial biological properties and wide applications in the food and pharmaceutical industries. In this study, the effects of 100 mg/kg (S1), 200 mg/kg (S2), 300 mg/kg (S3), and 400 mg/kg (S4) of dietary squalene supplementation over four weeks on growth performance, antioxidation, hepatoprotection, hypoxia tolerance, immune relative genes expression, and disease resistance of largemouth bass (Micropterus salmoides) were assessed. The results showed that squalene supplementation significantly increased the weight gain rate (WGR) and specific growth rate (SGR) of largemouth bass (p< 0.05). Serum glucose (GLU) levels were significantly decreased in all squalene-supplemented groups (p< 0.05). Squalene s