Influences of the short-term dietary carbohydrate restriction on the chicken cecal tonsil

This study aims to clarify influences of the short-term carbohydrate (CHO) restriction on plasma cells in chicken cecal tonsil (CT) using immunohistochemical and morphometrical techniques. Healthy male layer chickens were randomly divided into the control and three experimental groups. The three experimental groups were fed with diets containing 50%, 25%, and 0% CHO of that in the control diet, respectively. Following the experimental period for 7 days, CTs were collected from each chicken. Immunohistochemistry was performed to detect immunoglobulin (Ig) A, G and M. The density of IgA-immunoreactive cells was significantly lower in the lymphoid follicles (LFs) and diffuse lymphoid tissues (DLTs) in CTs of the 0% group compared to those of the other groups. There was a positive correlation between daily CHO intake and the density of IgA-immunoreactive cells in the DLTs and LFs. The density of IgM-immunoreactive cells was significantly decreased as daily CHO intake decreased, and there was a positive correlation between these two factors in both DLTs and LFs. The density of IgG-immunoreactive cells was significantly lower in DLTs of the 0% group than those in the control and 50% groups. The density of IgG-immunoreactive cells was significantly decreased with a decrease in daily CHO intake in DLT but not in LF. These findings demonstrated that dietary CHO had a significant effect on the density of plasma cells in the CTs exhibiting a declining trend with a decrease of ingested CHO volume.