The Effect of Continuous Antibiotic Feeding on X-Irradiation Mortality in Mice

Summary

1. X-Irradiation administered by the reported procedure significantly increased mortality over controls during a 40 week period. 2. Chlortetracycline administered in the feed at 20 parts per million significantly decreased irradiation mortality during the first 20 weeks of the experiment. 3. The marked chlortetracycline effect in Experiment 295 was due to modification of disease primarily due to Bartonella muris infection. 4. The lesser effect on mortality observed in Experiment 300 was probably due to antibacterial activity of the chlortetracycline on minor incident infections antagonized by the X-irradiation.