ADDITION OF CELLULOLYTIC CLOSTRIDIA TO THE BOVINE RUMEN AND PIG INTESTINAL-TRACT

Studies were conducted to determine whether intestinal cellulolytic ba cteria could be introduced into the bovine rumen or pig large intestin e, In the first study, the ruminal fluid of three cows was evacuated a nd replaced with 20 liters of buffer and 6 liters of the ruminal or sw ine cellulolytic organism Clostridium longisporum or Clostridium herbi vorans, respectively, The introduced organisms were the predominant ce llulolytic bacterium in the fluid (>10(7) cells ml(-1)) at 0 h, C. lon gisporum was still the predominant cellulolytic organism after 5 h, at 0.55 x 10(7) cells ml(-1); however, after 24 h the count of C. longis porum decreased to 0.05 x 10(7) cells ml(-1) compared with 2.8 x 10(7) cells ml(-1) for the total cellulolytic organisms, After 48 h, C. lon gisporum was no longer detectable, C. herbivorans was identified in on ly one of the three cows after 24 h and was not detected at 72 h. In a second study, when C. longisporum (50 ml; 10(7) cells ml(-1)) was inf used into the terminal ileum of seven pigs, it was not recovered when fecal samples were evaluated at 24, 48, or 72 h after infusion, These studies emphasize the competition that must be overcome to successfull y introduce organisms into an intestinal ecosystem. Furthermore, these studies suggest that C. longisporum is a transient organism in the bo vine rumen; however, C. herbivorans is part of the normal intestinal f lora of some pigs, although the role that it plays in fiber degradatio n in these pigs is unclear.