Intraspongious disc herniation (Schmorl’s node) and chronic spondylodiscitis in harbour porpoises Phocoena phocoena (Mammalia, Cetacea)

Pathological changes found in the vertebrae of two harbour porpoises (Phocoena phocoena) found along the North Sea shoreline of the Netherlands are described. One case can be diagnosed as intraspongious vertebral herniation of the nucleus pulposus (Schmorl’s node). The aetiology of Schmorl’s nodes is most probably resulting from idiopathic ischaemic (avascular) necrosis beneath the cartilaginous endplate, with secondary herniation of the nucleus pulposus into the vertebral body. The other case can be diagnosed as a severe case of spondylodiscitis, possibly resulting from an infection with Brucella ceti.