Drinking Slightly Acidic Electrolyzed Water Promotes Growth Performance, Improves Digestion, and Modulates...

This study assessed the effects of adding slightly acidic electrolyzed water (SAEW) to drinking water (0.3 and 0.6 mg/L) for 15 consecutive days on the growth performance, digestive enzyme activity, amino acid transporter gene expression, antioxidant activity, and immune function in weaned piglets. Using a randomized complete block design with pen as the experimental unit, 144 healthy weaned piglets were randomly assigned to three groups with four replicate pens per group according to weight and sex. During the entire experimental period, the average daily gain and average daily feed intake of the SAEW groups were significantly higher than those of the control (CON) group (p < 0.05). As compared to the CON group, the levels of α-amylase, β-amylase, lipase, and proteases in the duodenum increased in both SAEW groups (p < 0.05). Furthermore, 0.6 mg/L SAEW positively affected the mRNA levels of CAT1, PepT1, CAT2, EAAC1, rBAT, b0,+ AT, and 4F2hc in the jejunum and duodenum (p < 0.05). Regarding immune function, SAEW significantly decreased intestinal secretory immunoglobulin A levels in a dose-dependent manner (p < 0.05), while no significant changes were observed in serum immunoglobulin concentrations between the SAEW groups and the CON group. In terms of antioxidant status, SAEW significantly increased superoxide dismutase and glutathione peroxidase activities, but also increased malondialdehyde content in a dose-dependent manner. Despite the stronger promotion of intestinal amino acid transporters under 0.6 mg/L SAEW, this advantage failed to generate extra growth benefits alongside elevated oxidative damage. In conclusion, both tested SAEW concentrations exert positive effects on piglet growth and digestion; comprehensively balancing production benefits and redox safety, 0.3 mg/L SAEW is the optimal drinking water dosage for weaned piglets.