Salmonella Litchfield as a cause of an outbreak of salmonellosis in a herdof cattle

Salmonella Litchfield was isolated by the bacteriological examination of fa ecal samples from two febrile cows with diarrhoea. The herd was subsequentl y sampled on the basis of the likely prevalence of infection. As a result, S. Litchfield was detected in 17 of 44 faecal samples examined. A herd-spec ific vaccine was applied intranasally three times at one week intervals to all animals in the herd. The vaccination for calves was repeated, for a fou rth time. Three weeks after the administration of the vaccine no shedding, animals were detected in the herd. Sparrows were considered as the most lik ely source of infection.