Comparative analysis of jejunal morphology, antioxidant capacity and barrier function between Dahe pigs and Dahe black pigs

This research systematically compared the jejunum morphology, antioxidant capacity, barrier-related gene expression, and mucosal immune status between two Yunnan local pig breeds, namely Dahe pigs (DH) and Dahe black pigs (DHB), using histopathological staining, antioxidant assays, quantitative polymerase chain reaction (qPCR), immunofluorescence, and enzyme—linked immunosorbent assay (ELISA). The outcomes indicated that DHB presented a shallower crypt depth and a higher ratio of villus height to crypt depth, suggesting an enhanced capacity for nutrient absorption. In their jejunum, the activities of glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT) were significantly elevated, whereas the levels of malondialdehyde (MDA) were notably reduced. Conversely, DH displayed superior barrier function, with significantly higher expression levels of tight-junction proteins (Occludin, OCLN; Claudin-1, CLDN1 and Claudin-2, CLDN2) , mucin genes ( MUC1 ), defense-related proteins ( DEFB1, DEFB2 ), and immune-related genes (Interleukin-10, IL-10; Toll-like receptor 4, TLR4; Myeloid differentiation factor 88, MyD88; Immunoglobulin heavy chain A, IGHA; Joining chain, JCHAIN and Polymeric immunoglobulin receptor, PIGR ), along with a significant increase in IgG levels ( p < 0.05). These findings uncover the distinct physiological and immunological characteristics between the two breeds, offering theoretical underpinnings for precision nutrition and healthy breeding strategies in local pig populations.