Experimental paratuberculosis in calves following inoculation with a rabbit isolate of Mycobacterium avium subsp paratuberculosis

The role of wildlife species in the epidemiology of paratuberculosis has be en the subject of increased research efforts following the discovery of nat ural paratuberculosis in free-living rabbits from farms in east Scotland. T his paper describes the experimental inoculation of young calves with an is olate of Mycobacterium avium subsp. paratuberculosis recovered from a free- living rabbit. After a 6-month incubation period, all eight calves inoculat ed with the rabbit isolate had developed histopathological and/or microbiol ogical evidence of M. avium subsp. paratuberculosis infection. Similar resu lts were obtained from a group of calves infected with a bovine isolate of M. avium subsp. paratuberculosis. The virulence of the rabbit isolate for c alves demonstrated in this study suggests that rabbits are capable of passi ng paratuberculosis to domestic ruminants and that wildlife reservoirs of M . avium subsp. paratuberculosis should therefore be considered when formula ting control plans for the disease.