Congenital Abnormality of Cattle Showing Hydrocephalus and Hypoplastic Myopathy A Syndrome Different from Akabane Disease

Abstract

Four bovine fetuses stillborn almost at term occurring enzootically in 1974 and 1975 were affected with congenital abnormalities, such as the enlargement of the head, arthrogyrposis in the legs, kyphosis, torticollis, hydrocephalus, and hypoplastic myopathy. The lateral ventricles were enlarged in the longitudinal section of the brain. Three cervical muscles on the right side, the omotransversarius, sternomastoideus, and sternooccipitalis, were completely deficient in one fetus.
Histologically, stenosis of the mesencephalic canal and dysraphia of this and the spinal central canals were notced. Focal atrophy and disappearance of muscle fibers and the replacement of them by increased adipose tissue were found.
The neutralization tests for Akabane and BVD-MD virus was negative.
Pathologically and virologically, the congenital abnormality mentioned above must be a syndrome differentfrom Akabane disease and BVD-MD virus infection. The muscular change is concidered to be related tothe central nervous system.