Dietary hydrolyzable tannins reduce growth performance and induce histological damage of Chinese seabass (Lateolabrax maculatus)

Chinese seabass ( Lateolabrax maculatus ) is a popular carnivorous fish with delicious taste. Although the feed value of condensed tannins has been well documented for L. , information about effects hydrolyzable (HTs) on growth and health limited. This study was conducted to assess dietary HTs performance, body composition, intestinal digestive enzyme activities, serum metabolites, antioxidant immune response, intestine liver morphology . A total 640 were randomly divided into four groups replicates per group 40 replicate. Four diets prepared contain 0 (G0), 1 (G1), 2 (G2), 4 (G4) g/kg HTs. Fish fed apparent satiation twice day during 56-day feeding trial. Results showed that final weight, weight gain rate, specific intake linearly decreased p < 0.001) as increased. All had similar > 0.05) whole compositions. G2 G4 lower trypsin lipase activities than those G0 G1, whereas higher aspartate aminotransferase alanine G0. Serum capacity lysozyme 0.01), but malondialdehyde concentration increased 0.01) Intestinal villi in deformation, vacuolation cells began appear G1 aggravated should be used caution due their growth-inhibiting effect, HT level recommended less g/kg.