Selenium is one of the most vital trace elements regulating various body functions. Herein, we observe the effects of selenium-enriched probiotics on heart lesion in broiler chickens under high ambient temperature and explore the underlying mechanisms. Four different groups of broiler chickens were fed a corn-soybean basal diet having no Se supplementation (Con group), basal diet with the addition of probiotics (P group), a basal diet with Se supplementation in the form of sodium selenite (SS group, 0.30mg Se/kg) and basal diet with the addition of selenium enriched probiotics (SP group, 0.30mg Se/kg). The results showed that P, SS, or SP supplementation significantly (P<0.05) up-regulated mRNA expression of selenoproteins (GPx1, GPx4) and down-regulated heat shock proteins (Hsp60, Hsp70 and Hsp90) in heart as compared to Con, P and SS diets. Herein, we suggest that SP product can serve as a feasible nutritive supplement, capable of protecting the heart from toxic effect of oxidative stress in summer season.

Key words: Broiler chickens, Heart lesions, Heat shock proteins, Heat stress, Selenium-enriched probiotics, Selenoproteins