author(s)
P Visha, P Selvaraj and S Jayachandran

abstract
Selenium is an essential nutritional trace element having vital role in immunoprotection, antioxidant system and growth. Hence, selenium supplementation in the poultry has been regularly practiced using the inorganic and organic forms. These forms have the limitations of having narrow margin of safety and non specific binding to tissue proteins, hence an alternate form of selenium i.e. nanoselenium having higher bioavailability, higher margin of safety and seven-fold lower acute toxicity was synthesised. The nanoselenium (15-40 nm) synthesized was used for the biological trial in broiler chickens. The treatment groups were supplemented with 0.3 mg/kg sodium selenite (T2), 0.3 mg/kg organic selenium (T3), nanoselenium at three levels viz.0.15 (T4), and 0.3 (T5) and 0.6 mg/kg (T6) and (T1) group was the control, fed with the basal diet alone. The Sel W mRNA expression in the bursa of broiler chickens was studied. Supplementing 0.6 mg/kg nanoselenium in chickens resulted in highly increased expression of selenoprotein W in bursa of broiler chickens. As the selenoprotein SelW plays a vital role as antioxidant in both the immune mediating cells and the immune organs, especially during stress, the supplementation of 0.6 mg/kg nanoselenium can enhance the growth and immunity of the broiler chickens.