Glossoplegia in Large Animals
Glossoplegia, or paralysis of the tongue, is uncommon. Causes in horses include incorrect placement of obstetric snares in neonates during forced extraction, strangles, upper respiratory tract infections, meningitis, botulism, encephalomyelitis, leukoencephalomalacia, equine protozoal encephalomyelitis, and cerebral abscessation. Any condition that damages the hypoglossal nerve (cranial nerve XII), which is the major motor nerve to the muscles of the tongue, can result in glossoplegia. Neonates with glossoplegia must be monitored carefully to ensure they are able to eat. If necessary in affected foals, a nasogastric tube should be placed for administration of colostrum or IV plasma administered to prevent failure of passive transfer. Foals unable to maintain hydration may require IV fluid therapy and anti-inflammatory medication (eg, phenylbutazone, flunixin meglumine, or dexamethasone). Prophylaxis against gastric ulceration is also indicated. If the condition persists for >10 days after birth, the prognosis for regaining normal function is guarded. Inflammatory diseases and trauma may also result in transient glossoplegia. Occasionally, horses undergoing prolonged dental procedures involving excessive traction on the tongue can develop temporary glossoplegia. The prognosis of glossoplegia depends on the horse’s response to treatment for the primary condition.
In cattle, glossoplegia may accompany severe actinobacillosis (see Actinobacillosis). There may be complete paralysis of the tongue accompanied by necrosis of the tip. Such conditions are occasionally seen in outbreaks in feedlot cattle and may follow a bout of viral stomatitis.