Cataracts in swine

Abstract

Between 1979 and 1981, approximately 30% (208) of the sows and two boars from two pig farms in Southern Brazil were culled due to blindness. The animals remained lying most of the time and when standing had their heads in an attitude of alertness. Unusual movements, noises or aggressions from other animals frightened them, and when running they collided against the walls and other obstacles. Their pupils were whitish-gray in color and with direct light showed myosis. The eyes were collected at slaughter for ophthalmologic and histopathologic examinations. Lesions of uni or bilateral cortical cataracts of varying degrees were found. Histological examination revealed degeneration of the lens fibers and the formation of Morgagnian globules; the cortical epithelium presented remnants of nuclei and hypoplasia. Lesions were present only in the ocular lens. The probable etiology of the elevated incidence of cataracts is discussed and comments are made about the data of other workers related to the chronic Ingestion of hygromycin B in pig herds that showed a high incidence of this lesion.