Ginseng extract alleviates growth reduction, intestinal barrier damage, and oxidative stress in Lithobates catesbeiana induced by soybean meal

Abstract

The present study investigated the effects of ginseng extract on growth performance, antioxidant capacity, and intestinal health in bullfrogs fed high soybean meal diets. A total of four iso‑nitrogenous diets (crude protein, 40.00 %) and isolipidic diets (crude lipid, 8.00 %) were formulated and administered over a period of 8 weeks. A basal diet containing 10 % fishmeal (FM), a diet replacing all fishmeal with soybean meal (SBM), SBM supplemented with 0.05 % (GSP1) and 0.10 % (GSP2) ginseng extract. Compared to the SBM diet, the inclusion of dietary GSP2 notably alleviated the decline in growth performance and feed efficiency caused by soybean meal (P < 0.05). The levels of total protein and albumin in the serum of the GSP2 group were significantly increased, while the activities of alanine aminotransferase and aspartate aminotransferase showed a marked decrease (P < 0.05); The GSP2 group exhibited a significant increase in the activities of digestive enzymes, particularly lipase and trypsin, when compared to the SBM group. (P < 0.05). Antioxidant indices within the liver, encompassing catalase, superoxide dismutase, reduced glutathione exhibited significant improvements in both the GSP1 and GSP2 groups (P < 0.05). Diet with ginseng extract supplementation significantly improved intestinal morphology, decreased the gene expression of intestinal pro-inflammatory cytokines (P < 0.05). There was a significant shift in microbial populations, favoring beneficial bacteria such as Akkermansia and Sphinomonas in the GSP groups. In conclusion, the supplementation of ginseng extract effectively mitigates the adverse impacts of high soybean meal diets on bullfrog growth, liver health, and intestinal function, while simultaneously enhancing immune response and antioxidant capacity. Notably, optimal effects were observed at a supplementation level of 0.10 %.