Abstract: The purpose of this study was to establish an experimental animal model of poultry liver injury induced by acute heat stress.We examined the changes of liver damage enzyme (alanine transaminase (ALT),aspartate transaminase (AST),cholinesterase (CHE),lactate dehydrogenase (LDH)) in Kirin chicken serum and observed histopathological changes in liver after continuous heat stress.The results showed that pre-heat stress caused an extremely significant increasing in the activity of Kirin chicken liver damage enzymes AST and ALT (P <0.01),heat stress late,the activity of AST was significantly lower than normal levels (P <0.05),while the activity of ALT was extremely significantly lower than normal levels (P <0.01);During the continuous heat stress,the activity of CHE had been lower than normal levels,heat stress late,the activity of CHE was extremely significantly lower than normal levels (P <0.01);The activity of LDH increased and then decreased after the first fall change after continuous heat stress,heat stress late,the activity of LDH was extremely significantly higher than normal levels (P <0.01).The histopathological lesions in liver were characterized by typical vesicular degeneration and hepatocyte nuclear enrichment in Kirin chicken after continuous heat stress.A Kirin chicken model of liver injury was successfully established by continuous heat stress,this experimental model of liver cells had vesicular degeneration and hepatocyte nuclear enrichment.

Key words: heat stress; Kirin chicken; liver injury; experimental animal models