The effect of dietary 25-hydroxycholecalciferol on gut microbiota modulation, growth, meat quality and antioxidant status of growing-finishing pigs

Under intensive feeding conditions, bone quality of pigs is closely associated with the storage of Ca and P and is influenced by dietary Ca and P levels. Deficiency of these minerals can impair bone development and peak bone mass. Vitamin D3 can regulate intestinal absorption of Ca and P and maintain optimal homeostasis for bone mineralization. 25-Hydroxycholecalciferol (25OHD₃) is the active metabolite of regular vitamin D3 in vivo, which has a stronger biological activity and is more easily absorbed by the intestine than regular vitamin D3. Their study aimed to detect the potential influences of 25OHD₃ on pork quality, antioxidant status, and intestinal microbiota of growing-finishing pigs receiving low-phosphorus (P) diet. For that purpose, forty pigs were allocated into two groups including low-P diet (control group) and low-P diet supplemented with 50 μg/kg 25OHD₃ (25OHD₃ group). The whole experiment lasted for 88 days, including phase 1 (day 1–28), phase 2 (day 29–60), and phase 3 (day 61–88).

The results showed that 25OHD₃ supplementation tended to decrease feed conversion ratio in phase 3 and overall phase in comparison with the control group. 25OHD₃ increased serum contents of superoxide dismutase and glutathione peroxidase (GSH-Px), and decreased serum bone-specific alkaline phosphatase level. 25OHD₃ increased mucosal GSH-Px activity in the duodenum and ileum and tended to increase redness value and the activities of total antioxidant capacity and superoxide dismutase in longissimus dorsi. 25OHD₃ significantly upregulated the mRNA level of copper/ zinc superoxide dismutase and tended to change the mRNA levels of nuclear factor E2-related factor 2 and kelch-like ECH-associated protein 1 in longissimus dorsi. Moreover, 25OHD₃ supplementation decreased n-6/n-3 and iodine value in longissimus dorsi. For bone quality, 25OHD₃ supplementation increased calcium content, bone mineral content, and breaking strength in the metacarpal bones. Moreover, the colonic abundance of Lactobacillus was significantly higher in pigs fed with 25OHD₃, and exhibited a positive association with serum antioxidant status, pork quality, and bone characteristics.

Overall, the inclusion of 25OHD₃ in low P diet partly improved production performance, meat quality, antioxidant capacity, bone properties, and gut microbiota composition of growing-finishing pigs.

Zhang L, Long S, Wang H, Piao X. Dietary 25-hydroxycholecalciferol modulates gut microbiota and improves the growth, meat quality, and antioxidant status of growing-finishing pigs. Frontiers in Microbiology. 2023; 13: 1095509. https://doi.org/10.3389/fmicb.2022.1095509