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Groups of guinea pigs, hamsters and mice of 10 animals each, were injected with 9400, 940 and 94 viable particles of the mycelial phase of Blastomyces dermatitidis. Guinea pigs and hamsters were inoculated intratesticularly, and mice intravenously. It was possible to isolate the pathogen from the 3 species of animals with all the above mentioned doses.Hamsters inoculated intraperitoneally with the same inocula were considerably less susceptible than hamsters and guinea pigs injected intratesticularly. The mice injected intravenously also appeared more susceptible than hamsters inoculated intraperitoneally but due to small numbers of animals used, the assumption is not statistically significant. It appears that the intratesticular route in hamsters or guinea pigs may be a useful tool in the search of B. dermatitidis in its natural environment.

The susceptibility to drying of Paracoccidioides brasiliensis growing on sterilized soils, was investigated using 2 strains with different sporulating capacities. Decreased fungal viability was noted during the 31 day experimental periods. The sporulating strain surpassed its initial viability at the fifth day when 75 days old culture was used, but not with 135 days old culture. Higher water losses, as observed at the 12th and 31st days, were not tolerated by any of the strains. Some viable particles resisted desiccation for at least 31 days and maintained their pathogenicity for hamsters. Colonies developed on small pieces of wood in the inoculum.A progressive drop of viability of the fungus was observed when exposed to a 2°C. environmental temperature with 100% relative humidity. The sporulating strain seemed to resist the deteriorative effect more than did the non-sporulating strain.