A congenital anomaly in which the cerebellum and medulla oblongata protrude down into the cervical spinal canal through the foramen magnum; it is almost always associated with meningomyelocele, spina bifida and hydrocephalus. Recorded in calves, sheep and dogs.

Saunders Comprehensive Veterinary Dictionary 3rd Edition. Copyright © 2007 by D.C. Blood, V.P. Studdert and C.C. Gay, Elsevier. All rights reserved.