In an oxidation ditch below slatted floors in a pig-fattening farm the survival of Salmonella dublin, S. senftenberg and S. typhimurium was investigated. The temperatures in the aerated slurry did not exceed 33° C and apparently were not high enough to destroy the pathogens. All three strains of salmonella survived for at least 24 days. Salmonella dublin showed a lower viability than the other two strains. The use of slurry from infected animals as manure after its biological treatment by aeration in an oxidation ditch is therefore still hazardous for animals and man.