Abstract: [Objective] To assess dietary supplementation of different proportions of alfalfa meal on reproductive performance and serum biochemical, antioxidant and immune indexes of sows during late gestation. [Method] Single-factor completely randomized block design was used in this study. According to the principle of similar parity, body condition and expected date of delivery, a total of 40 Yorkshire×Landrace sows in late gestation were randomly assigned into 4 groups with 10 individuals for each group. The basal diets of the experimental sows were supplemented with alfalfa meal at proportions of 0 （control group）, 5% （5% alfalfa meal group）, 10% （10% alfalfa meal group） and 15% （15% alfalfa meal group）, respectively. The formal experiment started on the 85^th d of gestation and finished after delivery. On the 111^th d of gestation, blood samples of the experimental sows were collected, and the serum biochemical, antioxidant and immune indexes were determined; the litter size and alive litter size of sows were recorded within 12 h of delivery, and the birth litter weight and birth individual weight of piglets were determined. [Result] The birth litter weight of piglets in 10% alfalfa meal group was significantly （P<0.05） higher than that in the remaining groups. The serum albumin content and albumin-globulin ratio in 10% alfalfa meal group were significantly （P<0.05） lower than those in control group, and the serum glucose contents in 5% and 10% alfalfa meal groups were significantly （P<0.05） higher than those in control group. 5% and 10% alfalfa meal groups had significantly （P<0.05） increased serum total antioxidant capacity compared with control group; 10% alfalfa meal group had significantly （P<0.05） decreased serum malondialdehyde content compared with the remaining groups; 10% alfalfa meal group had significantly （P<0.05） elevated serum glutathione peroxidase activity compared with control group; 10% alfalfa meal group had significantly （P<0.05） improved serum superoxide dismutase activity compared with the remaining groups, and 5% and 15% alfalfa meal groups had significantly （P<0.05） improved serum superoxide dismutase activity compared with control group. [Conclusion] Dietary supplementation of alfalfa meal has certain ameliorative effects on reproductive performance and serum biochemical, antioxidant and immune indexes of sows during late gestation, and the adding proportion of 10% is recommended.

Key words: alfalfa meal, sows, late gestation, reproductive performance, serum indexes