Response of mice to transtracheal pulmonary inoculation of anaerobic bacteria

The transtracheal inoculation of a mixture of anaerobic bacteria, with or without hydrochloric acid, into the lungs of mice caused nonlethal pneumonia and abscesses in a minority of challenged animals. All animals cleared organisms and recovered by 30 days. Secondary infection with Escherichia coli was common but did not affect the response to challenge with the anaerobes.