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

Aflatoxin B-1 (AFB(1)), 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 AFB(1). However, the effects of Se against AFB(1)-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), AFB(1) group(0.3 mg/kg AFB(1) + 0.4 mg/kg Se), AFB(1) + Se group 1(0.3 mg/kg AFB(1) + 0.6 mg/kg Se), AFB(1) + Se group 11(0.3 mg/kg AFB(1) + 0.8 mg/kg Se) and AFB(1) + Se group III(0.3 mg/kg AFB(1) + 1.0 mg/kg Se) for 21 days (n = 60/group). Although the body weight in AFB(1) 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 AFB(1) group were decreased, compared with those in control group. Compared with those in AFB(1) group, the percentages of CD3+, CD3+CD4+ and CD3+CD8+ T cells in three AFB(1) + Se groups were increased from 14 to 21 days of age, and the contents of serum IL-2 and IFN-gamma in all AFB(1) + 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 AFB(1) + Se group III were lower than those in AFB(1) + 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 AFB(1) in the diets, and cellular immune function could be improved in chickens. (c) 2013 Elsevier Ltd. All rights reserved.