ExperimentalSalmonellainfection in calves. 2. Virulence and the spread of infection

Abstract

SUMMARYCalves with a serum ‘H’ titre of 1/160 developed a chronic form of salmonellosis after infection withS. dublin. Their growth rate was severely retarded by this illness. An aerogenic strain ofS. dublinwas found to be much more virulent than an anaerogenic strain. Faecal samples were superior to mouth swabs in detecting animals carryingS. dublin.During transport two uninoculated calves became infected and after transport stress, latent carriers ofS. dublinwith faecal samples negative forSalmonellafor 5 weeks, restarted excretion. At slaughterSalmonellawere isolated from viscera and organs and from the surface of five of six carcasses.