Abstract
Inbred germ-free Fischer 344 albino rats were evaluated as models for experimental candidiasis in order to investigate bacterial interaction with Candida albicans. Female rats were exposed to C. albicans in their drinking water and killed at intervals from 2 to 22 days after initial contact with the contaminant. C. albicans was cultured from their mouths from day 2 but from day 12 the number of colonies decreased. From day 2 to 9 all rats showed oral histological signs of candidal infestation, but after 9 days the number declined to 3 out of 9 at 22 days. The dorsal surface of the tongue was the best histological indicator of candidal infestation. All the rats had tongue lesions from day 4 to 9, and from day 6 there was also a concomitant localized loss of filiform papillae. The number of rats with all forms of tongue involvement also decreased after 9 days with only 3 out of 9 affected at 22 days. It is concluded that Fischer 344 inbred germ-free rats can be used on a limited scale as a model for candidiasis and bacterial interaction with C. albicans, the dorsal surface of the tongue would be the best site for studying candidal experimental lesions and it is probable that better results can be achieved with complete standardization of contamination and preparation procedures.