Further Studies on Coli Infection In Poultry

The efficacy of monovalent or polyvalent; heat-inactivated or formalinised E. coli- vaccines;adminstered via oralor intramuscular routes once or twice, were studied, through challenging with hom-ologous or heteroloeous E. coli strains viaintranasal, oral, intramuscular or intravenous routes. The following conclusions were collected from the finding, viz :-1- The six tested serotypes were pathogenic to day old chicks.2- Two types of vaccine (formol and heat-inactivat- ed) were prepared from 01:K1(L), 02:Kl(L) end3- FormaliniSed vaccines gave better results than the heat inactivated ones regardless of the route of adminstration4- Two doses per vaccine eBve results superior to those induced by one dose.5- Intramusculnr adminstration of both vaccines resul ted in the pr oduc t i.on of ° and K a~glutin- ins.