¹Department of Animal Science, Shahrekord University, Shahrekord 88186-34141, IRAN
²Animal Science Department, Qom Agricultural and Natural Source Research and Education Center (AREEO) Qom Iran, IRAN
³Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Education Ministry of China, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, CHINA
⁴Student Research Committee, Arak University of Medical Science, Arak, IRAN
⁵Department of Animal Health, Faculty of Animal Husbandry and Veterinary Sciences, The University of Agriculture Peshawar, PAKISTAN DOI : 10.9775/kvfd.2018.20930 The aim of this study was to investigate the effect of crateagus flavonoid extract in preventing pulmonary hypertension syndrome (PHS) in broiler chickens reared at high altitude, encountered ascites was evaluated. A 225 day-old broiler chickens (Ross-308) were randomly assigned to three treatments including different drinking levels of crateagus flavonoid extract (0, 0.1, and 0.2 mL per liter of drinking water) in a 42-day trial. Body weight gain were increased and feed conversion ratio were decreased significantly (P<0.05) when crateagus flavonoid extract was consumed by broiler chickens at levels of 0.1 and 0.2 mL per liter of drinking water in the both starting and growing stages, and throughout the trial. Overexpression of inducible nitric-oxide synthase in the heart was observed in chickens consumed different levels of crateagus flavonoid extract. Birds received crateagus flavonoid extract at levels of 0.1 and 0.2 mL had significantly (P<0.05) higher circulatory concentrations of nitric oxide but significantly (P<0.05) lower serum malondialdehyde concentration, hematocrit and heterophil to lymphocyte ratio compared to control group. Consuming crateagus flavonoid extract at levels of 0.1 and 0.2 mL reduced incidence of right ventricular hypertrophy and led to a significant decline in mortality from PHS. It was concluded that crateagus flavonoid extract is an effective medicinal plant derivative to prevent PHS and ascites in broiler chickens by lowering pulmonary blood pressure and increasing serum antioxidant capacities. Keywords : Chicken, Crateagus flavonoid extract, Cardiac disorder, Gene expression, Ascites