SULFATE REDUCTION AND METHANOGENESIS IN THE OVINE RUMEN AND PORCINE CECUM - A COMPARISON OF 2 MICROBIAL ECOSYSTEMS

A series of experiments was conducted to study the relationship betwee n methanogenesis and sulphate reduction in ovine rumen and porcine cae cum. Effect of 2-bromoethane sulphonate on hydrogen production by dige sta suggested that the most important H-2-disposal system in the rumen is methanogenesis and that methanogenesis is not predominant H-2-disp osal system in the porcine caecum. This inference was supported by the difference in predominant H-2-utilizers in these two microbial ecosys tems; Methanogenic bacteria (MB) were predominant in the rumen and sul phate reducing bacteria (SRB) were predominant in porcine caecum. Free sulphate levels in digesta appear to affect the relationship between MB and SRB. Sulphate levels in the rumen were likely to be insufficien t for SRB to outcompete MB.