Abstract
It was stated in the previous communication that following intranasal inoculation of Bact. lepisepticum into rabbits, a certain number of fatalities ensued. These animals died of pneumonia.
The time of onset of symptoms varied from 24 hours to three days following the inoculation. The rabbits developed signs of respiratory distress, appeared very ill, and showed serous or purulent discharges from the nares. Death ensued in from two to seven days as a rule.
Gross autopsy inspection showed fluid in the pleural cavity varying from a few drops to several cubic centimeters. In the acute cases the fluid was slightly cloudy; in the more prolonged cases it tended to be purulent. The appearance of the pleuræ varied in a corresponding manner from mere dullness to surfaces covered with fibrinous exudate. The lungs usually showed massive areas of consolidation; in early cases, on section, moist and hemorrhagic; in later cases, granular and dry. In some of the older cases the small bronchi exuded pus.
Histologically, the acute cases showed a pleural exudate consisting of fibrin, coagulated serum, and necrotic leucocytes. The pneumonic process seemed to start around the blood vessels where the adjacent alveoli were filled with fibrin, serum, and many red blood corpuscles. Elsewhere little change in the alveoli was seen. The blood vessels were surrounded by sheaths of fibrin containing many polymorphonuclear, mononuclear, and eosinophilic cells. The bronchi were normal. In more advanced cases the alveoli were filled with leucocytes in which the mononuclear type predominated. Finally, the involvement became general; usually an entire lobe was affected. The bronchi contained leucocytes and abscess-like formations occurred.
Bact. lepisepticum was demonstrable in the circulating blood, in the pleural fluid, and lungs.
It has, therefore, been possible to induce experimentallly in rabbits the several manifestations of the native respiratory disease called snuffles, pleuropneumonia, and septicemia.
Get full access to this article
View all access options for this article.