The role of astragalus polysaccharides in alleviating transport stress in piglets.

Transportation is a major stressor in swine production, inducing endocrine imbalance, oxidative stress, and immune dysfunction. This study investigated the effects of Astragalus polysaccharides (APS) on transport-induced stress in piglets. Piglets were assigned to a control group (CON), a transport stress group (TS), and two APS-supplemented groups receiving low (APS-L) or high (APS-H) doses. Blood samples were collected on 1, 3, and 7 days post-transportation to assess stress hormones, oxidative status, and inflammatory responses. Compared with the CON group, piglets of TS group significantly elevated norepinephrine (NE) and epinephrine (EPI) levels, increased reactive oxygen species (ROS), reduced glutathione peroxidase (GSH-Px) activity, and upregulated pro-inflammatory cytokines (TNF-α and IL-6). APS supplementation attenuated these transport-induced changes. At 1 day after transportation, piglets in both APS-L and APS-H groups exhibited lower NE, EPI, ROS, TNF-α, and IL-6 levels and higher GSH-Px activity than those in the TS group. The APS-H group showed greater protective effects than the APS-L group. By 3 and 7 days, oxidative and inflammatory parameters in APS-treated piglets gradually normalized, with the APS-H group showing values more comparable to those of the CON group. These results indicate that APS alleviates transport-induced stress by modulating the endocrine response, reducing oxidative stress, and attenuating inflammatory responses. APS supplementation may serve as a nutritional strategy to improve the health and welfare of piglets during transportation.