Abstract

Zhang Tie*, Wang Chun-guang and Zhao Xing-hua

The outer membrane protein (OMP) were extracted from38 strains of avian Escherichia coli which were isolated from the dead chickens of chicken breeding farms in 3 areas of Baoding, Qinhuangdao and Beijing by using ultrasonic cleaving and N- Lauroyl sarcosine sodium and OMP typing was done by SDS- PAGE to understand the genetic relationship of isolated strains from Avian pathogenic E. coli. There were 3 OMP types in these 38 strains of E. coli, in which, type OMP-1 was in common for 6 serotypes of isolated strains of O78, O 88, O2, O 18, O93 and O76, type OMP-?belonged to isolated strain of O76, OMP-? was found from all of the isolated strains of O93, O78, O88, O2, this indicated the identical serotype strain might belong to quite different OMP patterns and among isolated strains without any relationship in serotype could have the same OMP type. Among isolated strains with the same serotype strains might have genetic differentiation. And among the isolated strains of different serotypes, there might be the genetic relationship with different degree.