The effects of monthly formalin treatments on the survival of Salmonellae in earthen sheep yard debris.

Abstract

Abstract Extract During a recent survey of North Island sheep farms to determine the number of sheep deaths due to salmonellosis, salmonella organisms were recovered from 66 out of 141 typical earthen sheep yards on these properties (47%). The presence of salmonellae in these sheep yards correlated with the occurrence of clinical infection in sheep on the farms during the year of observation (Robinson and Royal, unpublished). The introduction and confinement of sheep into environments containing viable salmonellae can result in rapid appearance of these bacteria in the faeces, even though no clinical signs may be seen. A recent study of transported cattle in Australia showed that the percentage of animals with salmonellae in the rumen increased with length of time between leaving the farm and slaughter. During this period they were both exposed to salmonellae in the environment and deprived of feed (Grau et al., 1968 Grau, F. H., Brownlie, L. E. and Roberts, E. A. 1968. Effect of some preslaughter treatments on the salmonella population in the bovine rumen and faeces. J. appl. Bact., 31: 157–163. [Google Scholar]).