effects of enalapril on growth performance, ascites mortality, antioxidant status and blood parameters in broiler chickens under cold-induced ascites

six hundred 1-d-old male broilers (ross 308) were assigned to four experimental groups; each was composed of 5 floor pen replications of 30 birds including control (no enalapril), 15, 30 and 60 ppm enalapril in the drinking water. from d 21 to 49, all the chicks were exposed to low ambient temperature to induce ascites. mortalities were inspected to determine the cause of death and diagnose of ascites. at the end of the experiment (wk 7), 2 chickens from each replicate were randomly selected and slaughtered. body weight gain, feed intake and feed conversion ratio were calculated. plasma protein, glucose, red blood cell, white blood cell, triglyceride, high-density lipoprotein, malondialdehyde, the activity of alkaline phosphatase, aspartate aminotransferase, alanine aminotransferase, creatine kinase, total antioxidant capacity, superoxide dismutase, and glutathione peroxidase were also determined. results showed that enalapril for 30 and 60 ppm, significantly improved feed conversion ratio and enhanced body weight gain when measured at day 49. these levels of enalapril compared to the other groups, significantly reduced malondialdehyde level and glutathione peroxidase activity, but increased total antioxidant capacity and superoxide dismutase activity in plasma. moreover, enalapril at levels of 30 and 60 ppm, significantly reduced aspartate aminotransferase, alkaline phosphatase and creatine kinase activities in plasma. mortality due to ascites and right to total ventricular weight ratio were significantly low in groups received enalapril at greater levels (≥30 ppm). compared to the control, enalapril increased high-density lipoprotein. in conclusion, enalapril could improve growth performance and reduced mortality in broilers.