E..coli was recovered from 59.00% of septicaemic broiler chickens suffering enteritis, perihepatitis and airsacculitis. Pyocin typing of chosen E. coli  jsolates revealed two types. The first type was able to grow in the presence of pyocin (PREC). The second type was unable to grow in the presence of pyocin (PSEC). There is no correlation between pyocin typing and dermonecrotic test or pyocin typing and pathogenicity for day-old chickens. But, there is a correlation between dermonecrotic test and pathogenicity for day-old chicks. Thus, virulent types of E.coli can be detected through the dermonecrosis of their whole cell lysates (WCL) in the skin of guinea-pigs.