TREATMENT OP TENDER-MOUTHED HORSES. 209 



of the bone appears enlarged and the mucous membrane inflamed 

 and thickened. In other cases the periosteum is lacerated, exposing 

 the bone, and sometimes fracture is produced. In severe bruising 

 by the bit, suppurative ostitis and superficial necrosis with exfoliation 

 are common results. 



The careless use of severe bits ends in disease of the periosteum 

 or of the bone. Sometimes periostitis goes on to the formation of 

 exostoses, and occasionally the inflammatory process, complicated 

 by pus formation, extends to the jaw producing suppurative osteo- 

 myelitis. This is followed by marked enlargement of the bone 

 towards its body, where later an abscess may form. Necrotic 

 portions of bone, as large as a finger, may be discharged. Though 

 in such cases recovery is naturally slow, it is nearly always complete, 

 and no permanent injury is left. 



Symptoms. Attention is often first directed to an abrasion of 

 the mucous membrane by the excitability of the horse when reined 

 in. Bruises are recognised by the local swelling, redness and pain ; 

 wounds are directly visible. The parts are best examined by intro- 

 ducing the forefinger into the mouth ; and should pain, swelling, 

 or laceration of the membrane be detected, the diagnosis can be 

 confirmed by inspection. Periostitis can only be discovered 

 by touch, otherwise it often remains unnoticed, the horse's pulling 

 being assigned to bad temper, either on its part or on that of its 

 rider. Moderate pressure on the inflamed spot produces marked 

 pain. Wounds in the mucous membrane and necrosis of the bone 

 are generally offensive and easily detected with the finger or a 

 metallic probe. Osteomyelitis is recognised by swelling of the bone, 

 usually extending from above downwards towards the lower edge 

 of the jaw. When an abscess breaks at this point, fistula is a 

 common sequel. The probe often passes from the lower edge of 

 the jaw right into the mouth. Salivation and painful mastication, 

 though they sometimes occur, are not essential characteristics. 



Treatment must be based on the anatomical changes. If the parts 

 are merely abraded, it will be sufficient to rest the horse, or 

 to use a rubber bit, or nose-band, in place of a more severe bit, until 

 the epithelium has again grown. In wounds of the mucous mem- 

 brane, rest or absolute avoidance of bar bits is necessary. The parts 

 must be cleansed after each meal, and the horse muzzled or tied up. 

 The wound should subsequently be treated according to its character. 

 Immediately the bone or periosteum begins to suffer, the horse must 

 be rested. In uncomplicated periostitis recovery usually follows 

 this treatment in a week or ten days ; but in fracture, or suppurative 



