A Japanese Black calf, manifested by clinical signs of inability to stand and extending hind limbs after birth, was investigated clinically and pathologically. In the neurological inspection, gastrocnemius reflex and patellar tendon reflex of the right hind limb were hyperactive, and gastrocnemius reflex and crossed extension reflex of the left hind limb were also hyperactive. Magnetic resonance imaging (MRI) examination showed a cavity in the cord at the area of the third and fourth lumbar vertebrae in T2-weighted imaging. After the calf was euthanized, necropsy confirmed the swelling of the spinal cord at the third and fourth lumbar vertebrae. The histopathological examination confirmed that the central canal remained open, and the inner surface of central canal was lined with ependymal cells. Therefore, this calf was diagnosed to have hydromyelia of the lumbar cord. This study indicated that MRI was useful for diagnosing myelodysplasia such as hydoromyelia. This is the first report of hydoromyelia in Japanese Black calf.
Keywords: Japanese Black calf; hydromyelia; magnetic resonance imaging.