Pigs' intestinal barrier function is more refined with aging. (November 2022) - Yang, Shanshan
Abstract: The high mortality upon enteric virus infection in piglets causes huge economic losses. To control these infections, potential causes for this high susceptibility for enteric virus infections in younger piglets were analyzed by comparing the intestinal barrier between 1-week, 2-week and 4-week-old piglets. In this study, histological staining was used to analyze morphological differences in intestinal villi, real-time qPCR was performed to assess mRNA expression levels of genes that were related to viral infection and differentiation of immune cells, and flow cytometry was utilized to measure the frequencies of T cells. According to the results obtained, 1-week-old piglets have intestinal villi with shallower crypts, less well developed epithelial cells and a more immature immune system compared to older pigs. Moreover, high amounts of enteric virus invasion-assisting proteins but low amounts of resistant proteins in 1-week piglets could also be a reason for the high susceptibility of 1-week-old piglets. Highlights: Intestinal villi were physically more fragile in 1-week piglets compared with older pigs. Both adaptive immunity and innate immunity were weaker in 1-week piglets comparing with 2-week and 4-week old pigs. More enteric virus-assisting but less inhibitory proteins were in the intestines of 1-week piglets compared to older pigs.