Bdellovibrio and the intestinal flora of vertebrates.

Bdellovibrio strain MS7 force-fed to fish and frogs via an intragastric tube did not become an integral component of the intestinal microflora. Strain MS7 fed to mice in drinking water was not recovered from the intestinal tract of mice. However, in vitro, the organism multiplied in intestinal contents of frogs and mice. Bdellovibrio inoculated into rabbit ileal loops was greatly reduced in number within 24 h. It was concluded that strains MS7 could be considered nonpathogenic to animals, at least when introduced into the digestive tract, and that it is not feasible at the present time to lyse pathogenic, gram-negative bacteria in the alimentary tract with Bdellovibrio.