Effects of tannins supplementation to sheep diets on their performance, carcass parameters and meat fatty acid profile: A meta-analysis study

•Inclusion of tannin in the diet of lambs younger than 3 months of age reduces carcass weight.•Inclusion of tannin in the diet reduced in 17.5 % methane yield (CH4 g/kg of DMI).•Inclusion of tannins to the diets reduced meat malonaldehyde concentration by 12.15 %.•Tannins supplementation significantly depressed fatty acid biohydrogenation.