Tethered spinal cord related to caudal spinal dysraphism in a tailless Holstein calf.

A rare dysraphic caudal spinal anomaly, or caudal agenesis, comprising a tethered spinal cord, was found in a tailless Holstein calf that presented ataxia and paresis with analgesia of the hind limbs. The gently and slimly tapered conus medullaris was poorly formed between S2 and S3 which indicated that it was lying more caudally. The caudal end of the filum terminale adhered to the inner periosteum of the vertebral arch at S4, which is compatible with tethering of the spinal cord. The dysraphic changes from the secondary neurulation error and the longitudinal deranged cord morphology that may have been caused by the caudad traction due to tethering were confirmed. This represents the first bovine case with definitive morphological confirmation.