STUDIES TO AFFECT EXPERIMENTALLY THE PULMONARY CLEARANCE AND PASTEURELLA-MULTOCIDA-INDUCED PNEUMONIAS OF PIGS

The pulmonary clearance of Pasteurella multocida in weaner pigs was no t affected by Carrageenan and Silica, two substances which block the f unction of monocytes/macrophages. Neutropenia, caused by the applicati on of hydroxyurea, however, inhibit the pulmonary clearance markedly a nd reduced the severity of simultaneously induced pneumonias considera bly. This indicates the importance of polymorphonuclear neutrophils fo r early clearance mechanisms and their inflammation inducing and maint aining effects.