The protective role of condensed tannins on growth inhibition and enterohepatic injury induced by histamine in Chinese seabass (Lateolabrax maculatus)

Histamine has been documented to induce growth inhibition and tissue injury in animals, whereas information regarding the toxicity of histamine and the detoxication of condensed tannins (CT) in Chinese seabass (Lateolabrax maculatus) is rare. In this study, three diets were prepared to contain 0 g/kg of histamine (G1), 0.1 g/kg of histamine (G2), and 0.1 g/kg of histamine plus 1 g/kg of CT (G3). Fish were randomly divided into 12 tanks with 40 fish per tank and 4 tanks per diet. The results showed that the final body weight, weight gain rate, specific growth rate, total antioxidant capacity, and the activities of trypsin, lipase, catalase, superoxide dismutase and lysozyme were lower (P < 0.05) but the serum concentration of aspartate and alanine aminotransferases and glucose were higher (P < 0.05) in G2 than in G1 and G3. These parameters were similar (P > 0.05) between G1 and G3. The FCR was ranked as G2 > G3 > G1 (P < 0.05). Compared with G1 and G3, the deformation and atrophy of the intestinal villus and the vacuolation of hepatocytes were intensified in G2. In conclusion, 0.1 g/kg of histamine inhibited digestion, induced intestinal and liver injury, decreased antioxidant and immune capacity and reduced growth performance of L. maculatus. Supplementation of 1 g/kg of CT in the Lateolabrax maculatus diet alleviated histamine-induced toxicity owing to the protective effect of CT against oxidative damage. •Histamine inhibited the growth of Lateolabrax maculatus, whereas condensed tannins (CT) eliminated the inhibition.•Dietary histamine at 0.1 g/kg inhibited digestion and induced intestinal and liver injuries of fish.•Dietary CT at 1 g/kg alleviates histamine-induced toxicity to fish.