Intake, nutrient digestibility, nitrogen balance, serum metabolites and growth performance of lambs supplemented with Acacia mearnsii condensed tannin extract

The objective of this study was to determine the optimal amount of condensed tannins (CT) from Acacia mearnsii extract for inclusion in lamb diets. Forty noncastrated lambs with a mean age of four months and a mean body weight (BW) of 21.5 ± 1.9 kg were randomized into five treatment groups: 0, 20, 40, 60 and 80 g CT/kg dry matter (DM). Eight lambs were included in each treatment group to evaluate their intake, nutrient digestibility, nitrogen (N) balance, serum metabolites and growth performance. Intake of DM, crude protein (CP), ether extract (EE), neutral detergent fiber (NDFap), nonfibrous carbohydrates (NFC) and N, N retention, final BW, average daily gain (ADG), and ADG to DMI ratio quadratically (P