Discospondylitis in swine.

Gross and microscopic lesions of discospondylitis in swine are described. Gross lesions were characterized by areas of destruction and cavitation involving intervertebral discs and adjacent structures. Microscopically, acute lesions had hemorrhage and necrosis with infiltration of granulocytes and mononuclear cells. In chronic cases intradiscal structures were replaced by vascular connective tissue which contained plasma cells and lymphocytes. These lesions were most frequently associated with chronic erysipelas polyarthritis.