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YOKE-INJURIES IN WORKING OXEN. 
of the face should be made, to insure the removal of such foreign bodies 
as shots or particles of wood. 
(6.) YOKE-INJURIES IN WORKING OXEN. 
In working oxen the yoke often injures the head, necessitating skilled 
treatment. The causes of such injuries are very varied. Sometimes 
the skin alone, especially at the base of the horns, is bruised. Extrava¬ 
sation of blood under the skin is rare, though excoriations and even 
superficial necrosis of the skin occur frequently. Periostitis in the yoke 
bed is probably more common than is thought, but escapes observation. 
So long as the injury remains aseptic no great harm results, but when 
the parts become infected serious symptoms may follow. Extensive 
bruising of the skin with excoriation and free suppuration is rare, but 
furunculosis on the other hand is fairly common. Deep-seated suppura¬ 
tion, with necrosis of the periosteum, suppurative periostitis, necrosis 
of bone, and disease of the frontal sinuses, occurs in exceptional cases. 
Suppuration near the base of the horns is of particular importance, as 
the horns may thus be lost, seriously impairing the animal’s usefulness. 
The causes of these yoke-injuries are partly of a constitutional 
character. A narrow forehead concentrates the pressure on one spot, 
a bulging one causes the yoke to rock. Failure to keep clean the parts 
on which the yoke rests predisposes to injury, especially in wet weather. 
Badly-fitting yokes are a fruitful cause of bruises and excoriations; but 
want of skill in padding the yoke is less serious than unskilful padding- 
in the case of horse collars. On the other hand, unequal yoking and 
bad driving often leads to injury, one ox doing an unfairly large share of 
work and his companion correspondingly less. 
Symptoms. So long as the injuries are of an aseptic character the 
animal only shows a certain unwillingness to pull. This is often 
attributed to temper, and the veterinary surgeon is therefore rarely 
called in, his services being first invoked when there is some visible 
wound. Injuries are most liable to occur when the horns grow in a 
forward and downward direction. 
The prognosis is usually favourable ; even extensive necrosis of the 
frontal bone heals under suitable treatment. Injuries at the base of 
the horns must always be regarded with suspicion, as they may lead to 
loss or displacement of the horn so that the yoke can no longer be 
applied. 
Treatment is chiefly of a prophylactic character. The yoke should fit 
well and the yoke bed be inspected and cleaned frequently. The oxen 
working together should be of similar speed and temperament, and the 
driver should see that each does an equal share of work. The local 
