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Spinal deformities are sometimes seen in fishes.

Deformed Red Morwong
A deformed Red Morwong, Cheilodactylus fuscus. The fish was speared by 'Alex the Seal' near Sydney, New South Wales, 2004. Image: Alex the Seal
© Alex the Seal

Five major causes have been identified. These are:

  1. hereditary factors
  2. damage during embryonic development
  3. injuries
  4. diseases (including parasites)
  5. environmental influences (pollution)

Spinal deformities in farmed fishes can be caused by nutritional deficiencies (vitamins C and E and some amino acids).

Spinal deformities include:

  • scoliosis - an abnormal lateral curve to the vertebral column
  • lordosis - an abnormal inward (forward) curvature of the vertebral column
  • broken back


  1. Hutchins, B. & R. Swainston. 1986. Sea Fishes of Southern Australia. Complete Field Guide for Anglers and Divers. Swainston Publishing. Pp. 180.
  2. Toften, H. & M. Jobling. 1996. Development of spinal deformities in Atlantic salmon and Artic charr fed diets supplemented with oxytetracycline. Journal of Fish Biology. 49: 668-677.