Congenital multiple ocular defects with falciform retinal folds among Japanese black cattle.

To clarify the morphologic features of the ocular disease recently occurring among Japanese Black cattle in southern Kyushu, 6 globes from 3 Japanese Black cattle, between 11 and 20 months old (cow Nos. 1 to 3), were pathologically examined. Cow Nos. 1 and 2 were sired by the same Japanese Black bull, and cow No. 3 was sired by the ancestor (sire) of the former bull. The ocular lesions were pathologically similar to each other, except for the left eye of cow No. 1. The ocular lesions of 5 globes were characterized by microphthalmia, hypoplasia, and/or dysplasia of the lenses; persistence of the primary vitreous; and retinal dysplasia with total nonattachment. The left globe from cow No. 1 had no lens and severe hypoplasia and nonattachment of the retina. Because dysplastic retinal lesions that formed crescentic folds and a central column were the most characteristic features of the eyes, the falciform retinal fold with congenital nonattachment was the most likely disease entity. Although the cause of the ocular disease could not be clarified with the present study, an inherited ocular defect of the bull and its ancestor was suspected.