Effects of alfalfa saponin extract on growth performance and some antioxidant indices of weaned piglets

The experiment was conducted to determine the effects of alfalfa saponin extract (ASE) on growth performance and some antioxidant indices in weaned piglets. A total of 96 piglets (Duroc×Landrace×Large white) with 7.5±0.9 kg mean body weight weaned at 28 d of age were randomly assigned to 4 treatments (4 replicate pen per treatment with 3 gilts and 3 castrated males per pen). Diets containing 0, 5, 10, and 15 g ASE/kg were fed to piglets for 30 d. There was a linear improvement in finial body weight, average daily gain, and average daily feed intake (P=0.029, 0.003, and 0.042, respectively) as the level of ASE in pig diets increased. Glutathione peroxidase activity in serum, liver, and muscle of weaned pigs increased linearly (P=0.004, 0.047, and 0.053, respectively) as the level of ASE in pig diets increased. Superoxide dismutase activity in serum, liver, spleen, and muscle increased linearly (P=0.009, 0.006, 0.010, and 0.016, respectively). Serum catalase (CAT) activity increased quadratically (P=0.038), while kidney and muscle CAT activity increased linearly (P=0.051 and 0.052, respectively). Malondialdehyde (MDA) content in serum, liver, spleen, and muscle decreased linearly (P=0.032, 0.011, 0.008, and 0.007, respectively) as the level of ASE in pig diets increased. These findings indicated that dietary inclusion of ASE up to 15 g/kg could increase activity of some antioxidant enzymes in weaned piglets, as well as promote their growth.