Effect of Acute Temperature Stress on Energy Metabolism Immune Performance and Gut Microbiome of Largemouth Bass
The escalation of extreme weather events exerts a considerable influence on aquaculture particularly in the form of severe temperature stress which significantly sabotages the growth and health of fish Despite recognition of the crucial role that temperature plays current research on the effect of extreme temperature changes on fish health remains limited Hence we set up acute warming and cooling groups and then progressively reverted to the initial temperature to investigate largemouth bass energy metabolism immunological function and gut microbial response The fish antioxidant system responded to assist their environmental adaptation the serum superoxide dismutase and catalase were activated in the two groups and the total antioxidant capacity was also significantly elevated Distinct metabolic strategies were employed to cope with sudden environmental perturbations during the AC1 stage the largemouth bass exhibited an elevation in serum triglyceride and cholesterol levels alongside a reduction in blood glucose During the AW1 stage the serum levels of both TG and CHOL in the largemouth bass decreased Under the abrupt decrease in temperature the immunity of largemouth bass was strikingly affected with significant increases in AKP AST and ALT and a significant decrease in LZM Moreover we observed that the gut microbiome was distinct from water and feed and dominated by Firmicutes Fusobacteria Actinobacteria and Proteobacteria The gut morphology and the microbial community significantly changed after acute temperature stress Among the results indicate that dramatic weather changes particularly extreme cold may have a detrimental effect on the health and welfare of largemouth bass