Effect of methionine deficiency on duodenal and jejunal IgA + B cell count and immunoglobulin level of broilers.

Dietary methionine (met) is reported to enhance antibody production and boost cell-mediated immunity in chickens. Methionine deficiency has been shown to affect the development of the lymphoid organs and the generation of antibodies in chickens. This study is designed to investigate the effects of met deficiency on IgA+ B cells and immunoglobulins (sIgA, IgA, IgG and IgM) for a 6 week period in the duodenum and jejunum of Cobb broiler chicken using immunohistochemistry and enzyme-linked immunosorbent assay (ELISA) techniques. The results of the study showed that the IgA+ B cell count reduced significantly in the met deficiency group compared to the control group (P<0.05 or P<0.01). The contents of sIgA, IgA, IgG and IgM in the met deficiency group were significantly decreased (P<0.05 or P<0.01), especially at 28 and 42 days of age. It can be concluded that met deficiency exerts significant effects on the humoral immune system of intestinal mucosa. This study has provided valuable experimental insight which could be useful for future studies on the function of met in the intestine of humans and other animals.