Effect of X-Irradiation on Cecal Flora of the Rat.

Abstract

The cecal bacterial population of Sprague-Dawley rats, subjected to 825 r total-body X-irradiation and fasted for 24 hours before and after irradiation, is qualitatively different from that of pair-fed, non-irradiated control rats fasted for the same 48 hour period. Subsequent to irradiation cecal contents were plated on selective media and bacterial counts were performed. The normally predominant lactobacilli were decreased in number while the coliforms and azide-resistant bacteria were increased. A fasting period of 48 hours elicited no proportional change in bacterial types when counts were compared with those of normal fed rats.