Abstract:

The experiment was conducted with the objective of examining the effect of dietary high copper on the cellular apoptosis of brain tissue in the chicken by the methods of flow cytometry (FCM) and immune histochemical staining.360 one-day-old Avian chickens were randomly divided into six groups，and feed on diets as follows：Control (Cu 10.89 mg·kg^-1) and high copper (Cu 100 mg·kg^-1，high copper groupⅠ；Cu 200 mg·kg^-1，high copper groupⅡ；Cu 400 mg·kg^-1，high copper group Ⅲ；Cu 600 mg·kg^-1，high copper group Ⅳ；Cu 800 mg·kg^-1，high copper groupⅤ) for six weeks. By FCM，the percentage of apoptotic brain cells was significantly increased in high copper groups Ⅲ, Ⅳ and Ⅴcompared with that of control group （P＜0.05 or P＜0.01）. By the method of immune histochemical staining，the percentage of positive cells of Bax was significantly increased in high copper group Ⅲ, Ⅳ and Ⅴ (P＜0.01)，and the percentage of positive cells of Bcl-2 decreased (P＜0.05 or P＜0.01) in high copper group Ⅳ and Ⅴin comparison with those of control group. Also, copper-zinc-superoxidase （Cu-Zn-SOD）activity was obviously decreased and malondialdehyde （MDA）content markedly increased in high copper groups Ⅲ, Ⅳ and Ⅴ than that in control group. These results showed that dietary copper in excess of 400 mg·kg-1 induced the cellular apoptosis of brain tissue in chickens.