An epidemiological study of the incidence of salmonellas in pigs.

The incidence of salmonellas in pigs was studied in five farms and a bacon factory.Persistence and spread of salmonella excretion in pigs in a breeding establishment is described. Salmonella excretor boars and sows were responsible for the spread and perpetuation of infection in the farm. The possibility of spreading salmonella infection between farms through the distribution of excretor pigs was studied. Infection persisted and was related to the initial state of excretion of the pigs while at the farm of origin.The importance of feeding stuffs as a source of salmonella infection in pigs is discussed. Specially prepared heat treated pellets fed to the pigs prevented the introduction of salmonellas.