Ask the Vet: Amputations & Neurological Conditions

Is Wobbler Syndrome Hereditary? 

Horses with “Wobbler Syndrome” have damage to the spinal cord (most often the cervical portion) and this damage can be the result of infections, trauma, developmental abnormalities, nutritional deficiencies and excesses and even cancer. Horses with wobbler disease or Cervical Vertebral Malformation are part of the Wobbler Syndrome. Wobbler disease horses with malformations of the cervical spinal vertebra are most often seen in males in the Thoroughbred, Warmblood and Tennessee Walking horse breeds. This would suggest that genetics does play a part in the developmental aspect but it may often be only a predisposing cause as nutritional imbalances, rapid growth and some trauma often are required to produce the clinical signs.

When considering to breed a stallion or a mare with a history of being a “Wobbler” it is important to determine what the specific cause was (EPM infections probably do not have a genetic cause) and vitamin E deficiency is more likely a management problem (lack of green grass or Vitamin E supplements). I would recommend cervical radiographs to see if any malformations are present. The diet to the pregnant mare should be monitored carefully, especially for trace mineral deficiency such as copper.   

How Do Wobblers And Shivers Differ? 

Horses with shivers usually have more spastic movements of the hind legs, especially when backing than horses with “Wobblers.” Shivers horses do not show clinical signs of incoordination or ataxia. “Wobblers” can have spastic movements of the hind legs that can mimic the signs of shivers, especially if they have a concurrent hind leg lameness condition such as a foot abscess or arthritis of the joints of the lower legs. Recently, it has been shown that Shivers have a problem with the Purkinje cell axons in the cerebellum. The clinical signs of wobblers are a result of  damage to the spinal cord (most often the cervical portion) due to malformation, trauma, infections (EPM or Herpes) or nutritional deficiencies such as Vitamin E or trace minerals.

Courtesy of AAEP
Answered by, Barrie Grant, DVM, MS, DACVS, Bonsall, California