Effects of Lactobacillus rhamnosus Supplementation on Growth Performance, Immune Function, and Antioxidant Capacity of Newborn Foals

This study aimed to explore the effects of Lactobacillus rhamnosus GG (LGG) supplementation on the growth performance, immune function, and antioxidant capacity of foals. Fifteen newborn foals with similar birth weight (51.67 ± 6.07 kg) and good health were randomly assigned to three groups: control group and test groups I and II, which were supplemented with 5.0 × 109 CFU/day and 1.0 × 1010 CFU/day LGG, respectively, for 150 days. LGG intake increased the daily body height (P < .01) and weight (P < .01) gain of foals aged 120 to 150 days. The foals' IgA (P < .05) and IgG (P < .01) plasma levels increased at 30 and 150 days, respectively, and IL-6 plasma level increased at 90 days (P < .01). Plasma total antioxidant capacity level was significantly higher in test group I than in the control and test group II at 30 days (P < .01), whereas glutathione peroxidase level was significantly higher in test group II than in the control and test group I at 30 days (P < .01). Both test groups had significantly higher superoxide dismutase level than the control group (P < .01) and significantly decreased malondialdehyde plasma level at 90 and 150 days (P < .05). Overall, our findings indicate that dietary supplementation of LGG can improve the growth performance, immune function, and antioxidant capacity of newborn foals.