Colonisation of rabbits with Staphylococcus aureus after experimental infection with high and low virulence strains

Four groups of 12 rabbits each were inoculated in the nose with strains wit h suspected differences in virulence. In the two groups infected with strai ns from severe outbreaks, belonging to a rabbit-pathogenic biotype-phage ty pe combination, 6-12 rabbits were found positive at the successive bacterio logical samplings over a period of 28 days. In the two other groups, infect ed with strains obtained from rabbitries without a history of staphylococco sis, the number of Staphylococcus aureus positive animals quickly became ne gative but increased again after 1 week to 1-5 positive animals until the e nd of the experiment. Two rabbits in each group inoculated with a high viru lence strain developed purulent skin lesions, while in the groups inoculate d with low virulence strains, all animals remained clinically healthy. Resu lts indicate that colonisation capacity is an important virulence determina nt in rabbit staphylococcosis. (C) 2000 Elsevier Science B.V. All rights re served.