Duodenal morphology and immune responses of broiler chickens fed low doses of deoxynivalenol

Abstract

Morphometry and flow cytometry for intraepithelial lymphocyte phenotyping were used to determine the changes in duodenal mucosae after administration of low doses of deoxynivalenol in chickens. Moreover, functions of phagocytes and immunocompetent cells in peripheral blood were evaluated by flow cytometry. In total, sixty chickens of Ross hybrid broilers 308 were used in this experiment. Two experimental groups of 20 birds were continually fed for 14 days a diet containing deoxynivalenol at a dose of 1 and 3 mg·kg-1; 20 birds of the control group were fed uncontaminated diet. Morphometry showed only tendency to decrease the height of villi and surface area of duodenal mucosae in chickens fed the diet supplemented with 3 mg·kg-1 deoxynivalenol. Phenotyping of intraepithelial lymphocytes showed a decrease of CD45+ (P < 0.034) in duodenum of birds fed diets supplemented with deoxynivalenol. Examination of white blood cells showed a decrease of monocytes (P < 0.020) in chickens fed 3 mg·kg-1 of deoxynivalenol. Both experimental groups revealed higher metabolic burst of peripheral blood heterophils (P < 0.001). Phenotyping of immunocompetent cells showed an increase (P < 0.003) of CD3+ and a decrease (P < 0.001) of MHC II+ cells in peripheral blood of chickens fed with 3 mg·kg-1 dose of deoxynivalenol. The experimental feeding of chickens with deoxynivalenol resulted in immunomodulation of immunocompetent cells in duodenum and blood with mild atrophy of intestinal villi, mainly after the feeding of the dose of 3 mg·kg-1. We proved that even low doses of deoxynivalenol can cause changes in haemathological, immunological and morphological profiles already during two weeks, and lead to the activation of compensatoryadaptive mechanisms with unfavourable impact on health and performance of birds.