Hypervitaminosis A


Hypervitaminosis A (Image sourced from Bristol Biomed Image Archive with permission)
  • Main lesions:
  • In cats fed bovine liver for prolonged periods
    • Rich in vitamin A in grazing animals
    • Vertebrae fuse with each other due to bone proliferation - cervical spondylosis (ankylosing exostosis of the vertebral column), especially in the neck
  • Can also be teratogenic, especially in pigs (cleft plate and abortions)


  • May cause spondylosis of cervical vertebrae
  • Mainly on dorsolateral surface
  • Also in elbow and shoulder joints -> fixation of joint
  • May resolve with changes of diet