Effect of condensed tannins on growth performance, intestinal immune capacity and bacterial microbiomes of Lateolabrax japonicus

The objective of this study was to assess the effects of condensed tannins (CT) on growth performance and intestine health of juvenile Japanese seabass (Lateolabrax japonicus). Four diets were formulated to contain 0 (CT0), 100 (CT100), 200 (CT200) and 400 (CT400) mg/kg of pure CT isolated from grape seed. Quadruplicate groups of 20 fish were fed to apparent satiation two times daily during 56‐days feeding trial. At the end of trail, the blood and intestine samples were collected to analyse serum metabolites, intestinal enzyme activity and histomorphology, and bacterial microbiomes of the fish. Results indicated that growth performance and intestinal histomorphology of fish were not affected by treatments. Fish fed CT200 and CT400 had lower (p