Establishment of specific pathogen-free rabbits by inoculation of hysterectomy-derived rabbits with fecal suspension and anaerobic bacteria.

Establishment of a specific pathogen-free (SPF) rabbit colony was attempted by transferring a total of 127 hysterectomy-derived rabbits directly into a barrier room where SPF rats had been reared. All rabbits except four died of mucoid enteritis-like diarrhea during 2 and 6 weeks of age. A second experiment consisted of four groups of hysterectomy-derived rabbits including: (1) noninoculated controls; (2) rabbits inoculated with suspension of feces from the survivors; (3) rabbits inoculated with a bacterial inoculum (Bacteroides spp. and Eubacterium sp. isolated from conventional rabbits); and (4) rabbits inoculated with Streptococcus faecalis in addition to the inoculum used for group 3. All rabbits in group 1 died of diarrhea by 3 weeks of age. Survival rates of groups 2, 3 and 4 are 53%, 38% and 40%, respectively. On 7 days after the inoculation, Bacteroides was not recovered from fecal samples of group 1, but was recovered from many samples of the inoculated groups. Populations of Enterobacteriaceae and Clostridium in the samples in group 1 were larger than each of those in the inoculated groups. The present results suggest that the lethal diarrhea, after transferring hysterectomy-derived animals directly into a barrier room, can be controlled by inoculation with non-pathogenic anaerobes, especially Bacteroides.