Glässer's disease in piglets produced by intraperitoneal inoculation with Haemophilus parasuis.

Haemophilus parasuis was inoculated into the abdominal cavities of piglets. Its infective doses varied from 1.4 X 10(6) to 1.0 X 10(9) organisms. When inoculated with 1.0 X 10(9) or 1.6 X 10(8) organisms, piglets were affected with fibrinous polyserositis associated with arthritis and purulent meningitis. The three disorders were considered to be characteristic of Glässer's disease. Septicemia was also found in many of the infected piglets, some of which died within a few days after inoculation. No lesions were observed in piglets inoculated with 1.4 X 10(7) or 1.4 X 10(6) organisms. It was difficult to reisolate H.parasuis from lesions, especially those in the abdominal cavities of piglets killed on the 6th day after inoculation. Agglutinating and complement-fixing antibodies were present in the piglets with Glässer's syndrome examined on the 6th day after inoculation. Neither of them was detected in any piglet manifesting no clinical signs, except transient pyrexia.