Hereditary developmental disorders of the CNS, especially spinal cord, are of increasing importance in the bovine species. Therefore, congenital spinal malformations of non-hereditary origin have to be ruled out by carefully directed neuromorphological procedures. The two cases of malformation of the spinal cord reported were not accompanied by vertebral defects: The first one represents a complete diplomyelia of the caudal lumbo-sacral medulla in an 18 months old Brown Swiss heifer, the second one a circumscribed hydromyelia of the fifth lumbal segment, based on an incomplete dysraphic defect, in a 4 months old male German Simmental calf. Problems of diagnostic measures and of terminology, concerning differentiation between diplomyelia and diastematomyelia, were discussed in detail.