Effects Of Zinc On The Structure And Function Of Immune System In Ducklings

By establishing the phatholoical model of zinc deficiency (zinc content: 22.90mg/kg) and toxicity (zinc content:1300mg/kg) in ducklings , the effects of zinc deficiency and toxicity on the development of immune organs and immune functions were studied. Campaired with the control groups ,the absolute weight ,grouth index and cell cycle of immune organs, the ANAE positive rates of T lymphocytes in peripheral blood , the erythrocyte C3bRR and CIC rosette rates were singnificantly changed in the zinc-deficient and zinc-toxic ducklings. Histopathologically, lymphocytes of the immune organs were depleted,degenerated and necrotic in both zinc-deficient and zinc-toxic ducklings. Ultrastructurally,karyopyknosis and karyolysis occured in lymphocytes,and the mitochondria ,rough endoplasmic reticulum of lymphocytes in the immune organs were damaged .The nucleus were deformity ,the rmtochondrial and rough endoplasmic reticulum were swelling ,and the ribosomes were shed in reticular cells of thymus in zinc-deficient ducklings. The mitochondrial in lymphocytes of the immune organs were damaged, and reticular cells consisted of many primary and secondary lysosoms as well as phagocytes in zinc-toxic ducklings. Results demonstrated that zinc deficiency and toxicity greatly suppressed the development of immune organs, caused obvious pathological injury of the immune organs, weakened the funcion of humoral,cellular and erythrocyte immunity.