Dietary Berberine Improves Liver and Intestinal Health for Hybrid Yellow Catfish ( Pelteobagrus fulvidraco ♀ ×  Pelteobagrus vachelli ♂) Suffered Dual Stress From Soybean Meal‐Induced Enteritis and Lipopolysaccharide

In order to investigate the effect of dietary berberine (BBR) on lipopolysaccharide (LPS) stimulation in hybrid yellow catfish with soybean meal‐induced enteritis (SBMIE), two diets were formulated: a control diet containing 33.75% soybean meal (SBM) and an experimental diet with 33.75% SBM supplemented with 75 mg/kg BBR. After 42 days of feeding, the fish from each dietary group were divided into two subgroups, one of which was subsequently challenged with LPS, while the other was not. Then, liver and hindgut tissues were sampled at 12 and 24 h postinfection, respectively, to analyze the oxidative stress, antioxidant capacity, histopathology, immune response, and apoptosis. The results revealed that dietary SBM of 33.75% significantly induced oxidative stress, histopathological damage, immune dysfunction, and apoptosis in both the liver and hindgut of hybrid yellow catfish. Furthermore, exposure to LPS exacerbated these symptoms. In contrast, 75 mg/kg BBR in the diet significantly improved liver and hindgut health via enhancing oxidative stress resistance, antioxidative capacity, and the intestinal barrier function, without affecting growth or feed utilization. Also, it effectively protected liver and intestinal health from LPS damage. The subgroup infected with LPS in the dietary BBR group showed marked improvements in all assessed parameters, including oxidative stress, antioxidant capacity, histopathology damage, immune dysfunction, liver apoptosis, and intestinal physical barrier, when compared with those in the subgroup infected with LPS in the control group. In conclusion, BBR represents a promising feed additive for enhancing fish health under combined stress from SBM and LPS‐induced stress.