RESUMO
The experiment was conducted to examine the effect of zinc toxicity on the peripheral blood T-lymphocyte by the method of flow cytometry(FCM) and ANAE.200 one-day-old Avian broilers were divided into four groups,and fed with the diets as follows:①control group(Zn 100 mg/kg diet) and ② zinc toxic groups(Zn 1 500 mg/kg diet,zinc toxic group Ⅰ;Zn 2 000 mg/kg diet,zinc toxic group Ⅱ;Zn 2 500 mg/kg diet,zinc toxic group Ⅲ) for seven weeks.The ANAE positive ratios of the peripheral blood T-lymphocytes were much lower in the three zinc toxic groups than that in control group at 7 weeks of age.CD4+ T cell numbers were reduced from 2 to 7 weekds of age in zinc toxic group Ⅲ and from 6 to 7 weeks of age in zinc toxic group Ⅱ,as compared with that of control group.The numbers of CD8+ T cell decreased at 2 and 4 weeks of age in zinc toxic groups Ⅱ and Ⅲ,and at 7 weeks of age in zinc grups Ⅰ and Ⅲ.CD4+/CD8+ ratio was higher at 2 and 4 weeks age,and lower at 6 and 7 weeks of age in zinc toxic groups Ⅰ,Ⅱ and Ⅲ than in control group.The results showed that zinc toxicity would suppress the development of T-lymphocytes and reduce the peripheral blood T-lymphocyte populations.Potential mechanism underlying these observations are also discussed.
RESUMO
Objective: To investigate the influence and mechanism of zinc toxicity on the stucture and function of immune organs in ducks. Methods: By establishing the pathological model of zinc toxicity in ducks, some immunological methods, light and electron microscopes were used to check the changes in the stucture and function of immune system. Results: (1) The body weight of ZT group was significantly lower than that of ZC group after 3 weeks (P