Segmental spinal dysgenesis with caudal agenesis in a Holsteincalf

[摘要] A rare complex dysraphic malformation, comprising segmental spinal dysgenesis with caudalagenesis, was found in a Holstein calf that was unable to stand and was slightly short atthe lumbosacral spine with taillessness. The thoracolumbar and sacrococcygeal regions ofthe midline axial segments showed severe deformities. In the spinal cord, thethoracolumbar region showed severe constriction with myelodysplastic changes, and thesacrococcygeal region showed dorsoventral separation with connection to a neural mass. Inthe spine, vertebral anomalies according to the degree of the segmentation error wereconfirmed. The cervical and thoracic segments also showed milder dysraphic changes. Thesechanges suggest a multisegmental causal insult impairing the early embryonic notochord.This represents the first bovine case definitively confirmed morphologically.

[学科分类] 兽医学

[关键词] caudal agenesis;complex dysraphic malformation;Holstein calf;segmental spinal dysgenesis