Influence of drying on the survival of anaerobic fungi in rumen digesta and faeces of cattle

Abstract Tolerance of anaerobic fungi in the faeces and rumen digesta of cattle to drying in air at approx. 20°C or 39°C was investigated. Anaerobic fungi were able to survive in dried faeces, but no significant survival was observed in digesta collected from five different regions of the rumen. Anaerobic fungi in faeces also survived when samples were dried in the presence of rumen digesta. When dried in the presence of sterile faeces, however, anaerobic fungi in rumen digesta failed to survive the drying process. The most plausible explanation for these results is that, during passage from the rumen to the rectum, anaerobic fungi undergo a transition to a dormant form resistant to air-drying.