Spleen lesions of hemorrhagic enteritis of turkeys.

Spleens from turkeys were examined at intervals after intravenous inoculation with hemorrhagic enteritis virus. Spleen size increased until the 4th day after inoculation. On the 5th day, spleen size was markedly reduced and continued to approach normal size. Hemorrhagic enteritis antigen reached a peak concentration on the 2nd day, was reduced in concentration on the 3rd day, and was absent by the 4th day. Hemorrhagic enteritis precipitin antibody was present in all serum samples taken after the 10th day. Necrosis of lymphoid cells in the white pulp was prominent in the 1st day. Proliferation of immature-appearing cells on the 2nd, 3rd, and 4th days coincided with a lower virus antigen content in the spleen. Massive disintegration of the white pulp, associated with the appearance of small dense-staining lymphocytes, began on the 4th day. By the 5th day only the splenic arteries and the surrounding reticular cells remained. Restoration of normal-appearing white pulp was completed by the 8th day. No correlation was noted between splenic lesions and intestinal lesions. Many stages in the development of typical intranuclear inclusions were observed.