Abstract

Anaerobic fungal isolates Caecomyces sp. from the feces of elephant andOrpinomyces sp. from buffalo rumen were co-cultured in-vitro with rumen bacterial and protozoal fractions collected from buffalo to observe the possible fate of these fungi in the rumen, if inoculated as microbial-feed supplements. When co-cultured together or separately with rumen bacteria and protozoa, Caecomycessp. was adversely affected. However, bacterial and protozoal counts were higher, compared to the counts when grown alone. Similar patterns of results were observed when Orpinomyces sp. was grown in co-culture with bacteria and protozoa separately as well as together, indicating that it is possibly the inhibitory action of bacteria and protozoa, and not inter-species competition, that affects the growth of fungi preventing them from attaining their full fibre-degrading potential. Conversely, although fungal counts were lowered during their co-culturing with bacterial and protozoal fractions, their co-culturing increased the FPase activity of the co-cultured fraction which could be the apparent reason for enhanced fibre degradation.

Key words: Rumen microflora, anaerobic fungi, microbial interactions, fibre degradation.