عنوان مقاله [English]
In order to investigate commercial plant growth promoter (CPGP) (Cinnamaldehyde, Capsaicin, and Carvacrol) on performance, and cecal microbial population of broiler chickens under heat stress, an experiment was done with 4 treatments and 4 replicates with 176 one-day-old chicks in completely randomized design. Treatments were control (without phytogenic), and different levels of CPGP (100, 200, and 300 mg/kg). Heat stress was performed from 22 days of age. The results of experiment showed that dietary inclusion of 200 mg/kg of CPGP to the diet decreased feed intake (P<0.05) compared to the birds receiving the control diet at the starter period. At the whole period of experiment, dietary inclusion of 300 mg/kg of CPGP improved body weight gain compared to the other treatments (P<0.05). Also, at the starter and whole period of experiment, dietary inclusion of 300 mg/kg of CPGP had better feed conversion ratio compared to the control diet and 100 mg/kg of CPGP (P<0.05). The birds that consumed 300 mg/kg of CPGP significantly had lower abdominal fat pad compared to the birds receiving the control diet and the diet containing 100 mg/kg of CPGP (P<0.05). Dietary inclusion of CPGP had not significant effect on cecal bacterial population and blood parameters of broiler chickens (P>0.05). It can be concluded that dietary inclusion of 300 mg/kg of CPGP can be improved performance and decrease abdominal fat pad of broiler chickens under heat stress.