Abstract: The relationship between heart damages and HSPs mRNA of heat stressed broilers was studied using spectrophotometer, histopathological technique and fluorescence quantitative reverse transcription PCR (FQ RT-PCR). The results showed that the activity of creatine kinase (CK) and glutamic-pyruvic transaminase (GPT) was fluctuant during the persistent heat stress. The major lesions in the myocardial fibers were degeneration and necrosis. The transcription of constitutive or cognate heat shock protein 70 (HSC70) mRNA changed. The transcription of heat shock protein 70 (HSP70) mRNA significantly increased in the course of persistent heat stress. The results also suggested that the change of HSC70 mRNA was contrary to the activity of CK, and the level of HSC70 mRNA transcription could used as a symbol of myocardial cell damages in the course of persistent heat stress.

Key words: Broiler, Heat shock protein (HSP), Fluorescence quantitative reverse transcription PCR(FQ RT-PCR), Heart, Heat stress