1973 Volume 26 Issue 2 Pages 70-75
On four hog farms in Okayama Prefecture, a disease broke out among pigs 3 to 4 months of age during a period from November, 1970, to April, 1971. It caused pyrexia, tachypnea, anorexia, diarrhea, constipation, and cyanosis of the auricles, four extremities, and hypogastric region, and eventual death, which usually occurred after a course of 1 to 4 days. It was diagnosed as pratyphoid fever due toSalmonella choleraesuis.
Autopsy revealed pulmonary edema, congestion of the pulmonary apex and lobus medius, splenomegaly and obscurity of follicles in the spleen, cloudy swelling of the liver, mild petechiae beneath the renal capsule and in the cardiac coronary region, and hyperemia and hemorrhage of principal lymph nodes.
Histological examination revealed hyaline degeneration and thrombosis of small blood vessels of the lung and septal interstitial pneumonitis, activation of the reticuloendothelial cells of the liver and lymph nodes, and well-defied necrosis in pulmonary lobules and diffuse necrosis in lymph nodes.
Sal. choleraesuiswas isolated purely from principal organs of dead pigs. Pigs which had withstood the infection showed an increase in agglutination titer of blood against this organism. The average morbidity and fatality were 21.3 and 34.8%, respectively, on the four hog farms.
