Effects of sodium selenite on the decreased percentage of T cell subsets, contents of serum IL-2 and IFN- gamma induced by aflatoxin B₁ in broilers.

摘要

Aflatoxin B₁ (AFB₁), especially inducing hepatocellular carcinoma and immunosuppression of animals, poses a serious healthy and economic hazard to both humans and livestock. Animal studies have demonstrated that selenium (Se) provides anticarcinogenic and antimutagenic effects against AFB₁. However, the effects of Se against AFB₁-induced immunosuppression were rarely reported. To test this, three hundred 1-day-old male avian broilers were divided into five groups and fed on control diet (0.4 mg/kg Se), AFB₁ group(0.3 mg/kg AFB₁+0.4 mg/kg Se), AFB₁+Se group I(0.3 mg/kg AFB₁+0.6 mg/kg Se), AFB₁+Se group II(0.3 mg/kg AFB₁+0.8 mg/kg Se) and AFB₁+Se group III(0.3 mg/kg AFB₁+1.0 mg/kg Se) for 21 days (n=60/group). Although the body weight in AFB₁ group was lower than that in control group at 14 days of age, there no significant differences on body weight among five groups at 7 and 21 days of age. No evident clinical symptoms were observed among five groups from 7 to 21 days of age. The percentages of peripheral blood CD₃+, CD₃+CD₄+, CD₃+CD₈+ and the contents of serum IL-2 and IFN- gamma in AFB₁ group were decreased, compared with those in control group. Compared with those in AFB₁ group, the percentages of CD₃+, CD₃+CD₄+ and CD₃+CD₈+T cells in three AFB₁+Se groups were increased from 14 to 21 days of age, and the contents of serum IL-2 and IFN- gamma in all AFB₁+Se groups were increased from 7 to 21 days of age. On the contrary, the percentages of CD₃+, CD₃+CD₄+ and CD₃+CD₈+T cells, and the contents of Serum IL-2 and IFN- gamma in AFB₁+Se group III were lower than those in AFB₁+Se group II. It was concluded that 0.6 and 0.8 mg/kg Se could increase the decreased percentages of peripheral blood T-cell subsets and the contents of serum IL-2 and IFN- gamma induced by 0.3 mg/kg AFB₁ in the diets, and cellular immune function could be improved in chickens.