Dietary Sodium Lactate Alleviates Ammonia Stress‐Induced Growth Impairment, Oxidative Damage and Metabolic Disorder in Juvenile Yellow Catfish

Abstract

This study aimed to analyze the beneficial impacts of dietary sodium lactate (SLA) on growth, metabolism, and ammonia resistance in juvenile yellow catfish (Pelteobagrus fulvidraco) under chronic ammonia stress. In an 8‐week experiment, 360 healthy juveniles (1.64 ± 0.03 g) were assigned to 4 groups (3 replicates, 30 fish/replicate), fed either a basal diet or a 1.00% SLA‐supplemented diet with or without 2.5 mg/L total ammonia nitrogen (T‐AN) exposure. The results showed that dietary SLA supplementation effectively ameliorated growth inhibition and impaired feed efficiency caused by chronic ammonia stress. At the digestive level, SLA supplementation significantly enhanced the activities of intestinal lipase and pepsin, with no significant change in amylase activity. In addition, dietary SLA positively regulated serum biochemical profiles, improved hepatic antioxidant capacity, and alleviated oxidative damage induced by long‐term ammonia exposure. At the molecular level, SLA modulated the expression of hepatic glucose metabolism‐related genes, reversed the inhibitory effect of chronic ammonia stress on muscle growth‐related gene expression, and downregulated the growth‐suppressive gene mstn. Collectively, dietary SLA can effectively mitigate the adverse effects of chronic ammonia stress on juvenile yellow catfish by improving digestive function, regulating metabolic homeostasis, and alleviating hepatic oxidative damage and ammonia toxicity. This study supports the application of SLA as a functional feed additive in aquaculture.