Gorgan University of Agricultural Sciences and Natural Resources Poultry Science Journal 2345-6604 5 2 2017 10 01 Effects of Coenzyme Q10 and Vitamin C on Growth Performance and Blood Components in Broiler Chickens under Heat Stress 145 152 3745 10.22069/psj.2017.13733.1272 EN S Raeisi-Zeydabad Department of Animal Science, Faculty of Agriculture, University of Jiroft, Jiroft, Iran R Mirmahmoudi Department of Animal Science, Faculty of Agriculture, University of Jiroft, Jiroft, Iran O Esmaeilipour Department of Animal Science, Faculty of Agriculture, University of Jiroft, Jiroft, Iran M Mazhari Department of Animal Science, Faculty of Agriculture, University of Jiroft, Jiroft, Iran Journal Article 2017 07 29 This experiment was carried out to study the effects of Coenzyme Q10 (CoQ10) and vitamin C (VC) on growth performance and blood biochemistry in broiler chickens under heat stress conditions. One of three levels of CoQ10 (0, 20, and 40 mg/kg of diet) and one of two levels of VC (0 and 250 mg/kg of diet) were supplemented to diets of chicks (from 1-42 d of age) in a 3 × 2 factorial arrangement. Each dietary treatment had four replicate pens (10 chicks/pen). In order to create chronic heat stress, the house temperature was set at an ambient temperature of 35±2°C for 8 hrs daily (09:00 to 17:00) between 25-42 d of age. Feed intake, body weight gain (BWG), and feed to gain ratio (F:G) were recorded at d 10, 25 and 42. At the end of experiment, two chicks/pen were randomly selected to assess blood components. CoQ10 supplementation improved BWG and F:G during 11-25 days, 26-42 days, and the whole period of the experiment (<em>P </em>< 0.05), while VC supplementation improved BWG and F:G only during 11-25 d of age. Blood glucose, cholesterol and triglycerides concentrations were reduced (<em>P < </em>0.05) by addition of CoQ10 to the diet. Both Supplementation of CoQ10 and VC together lowered heterophil (H) count but increased lymphocyte (L) count, thereby reducing H/L ratio (<em>P </em>< 0.05). Serum concentrations of corticosterone and T4 were positively affected by dietary supplementation of CoQ10 (<em>P </em>< 0.05), but no differences were obtained with addition of VC to the diet. In conclusion, our observations demonstrated that dietary supplementation of 40 mg/kg CoQ10 or 250 mg/kg VC improves the growth performance of broiler chickens under the heat stress. https://psj.gau.ac.ir/article_3745_baab2a21ffe6104cee063dccefab03ac.pdf