PRICKING. 321 



of any pus that may be present. A poultice should also be 

 applied and the animal kei)t perfectly quiet. In some cases 

 dark-coloured blood will escape, or the discharge may con- 

 sist of serum or pure pus. Whatever it consists of, it must 

 escape in some way ; and if a dependent opening is not 

 made for it, the probabilities are that it will come out at 

 the coronet and form a quittor, or that the limb may 

 become gangrenous. In other cases the irritation and in- 

 flammation may give rise to alarming symptoms, be 

 followed by extensive suppuration, and cause separation of 

 the horny from the sensitive laminae to take place. The 

 sole becomes under-run, and this has to be cut away and 

 new horn allowed to grow, the animal in the meantime 

 being allowed to rest. If there are any signs of irritative 

 fever manifested, the animal should be given a laxative, and 

 the symptoms combated as they arise. The diet of the 

 animal should be of a laxative character. If fungoid 

 growths spring up they are to be reduced by caustics, as 

 argenti nitras in solution, antimonii chloride, etc., or in 

 .exceptional cases the hot iron may be used. 



CANKER. 



Canker consists of a malignant growth of a fungoid 

 nature, and usually occurs as a result of an injury, as 

 punctures. Thrush also is said to be a cause of canker. 

 It may be situated near the point of the frog, or may occur 

 in the cleft of the same structure. Some horses are more 

 or less predisposed to canker, heavy horses more par- 

 ticularly. Separation of the sensitive from the insensitive 

 sole takes place, and a growth of an extremely vascular 

 nature springs up and extends partially over the foot, 

 causing a considerable amount of suffering. On the 

 American continent canker usually occurs in a mild or non- 

 malignant form. 



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