204444ae_seases___Iowa_State_University__Name
[Etiology] Unknown but some evidence of hereditary predisposition. [Signs - Lesions] Raised, expanding circular lesions in 12-14 week old pigs. Lesions usually on ventral abdomen, less often elsewhere. [Comments] Lesions resolve within a few weeks without treatment. Disease may go unnoticed unless ventrum is examined. [Name] 
Pityriasis rosea
Skin Lesions and Diseases | Iowa State University
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