CANKER. 401 



should not be dried up too quickly, and in some cases not dried up at all. If a 

 young colt, fat and full of blood, has a bad thrush, with much discharge, it will 

 be prudent to accompany the attempt at cure by a dose of physic or a course 

 of diuretics. A few diuretics may not be injurious when we are endeavouring 

 to dry up thrush in older horses : but the disease can scarcely be attacked too 

 soon, or subdued too rapidly, and especially when it steals on so insidiously, 

 and has such fatal consequences in its train. If the heels once begin to contract 

 through the baneful effect of thrush, it will, with difficulty, or not at all, be 

 afterwards removed. 



There are many recipes to stop a running thrush. Almost every application of 

 an astringent, but not of too caustic nature will have the effect. The common 

 JEgyptiacum (vinegar boiled with honey and verdigrease) is a good lini- 

 ment ; but the most effectual and the safest drying up the discharge speedily, 

 but not suddenly is a paste composed of blue vitriol, tar, and lard, in propor- 

 tions according to the virulence of the canker. A pledget of tow covered with it 

 should be introduced as deeply as possible, yet without force, into the cleft of the 

 frog every night, and removed in the morning before the horse goes to work. 

 Attention should at the same time, as in other diseases of the foot, be paid to the 

 apparent cause of the complaint, and that cause should be carefully obviated or 

 removed. Before the application of the paste, the frog should be examined, and 

 every loose part of the horn or hardened discharge removed ; and if much of the 

 frog is then exposed, a larger and wider piece of tow covered with the paste may 

 be placed over it, in addition to the pledget introduced into the cleft of the frog. 

 It will be necessary to preserve the frog moist while the cure is in progress, and 

 this may be done by filling the feet with tow covered by common stopping, or 

 using the felt pad, likewise covered with it. Turning out would be prejudicial 

 rather than of benefit to thrushy feet, except the dressing is continued, and the 

 feet defended from moisture. 



CANKER 



Is a separation of the horn from the sensible part of the foot, and the sprouting 

 of fungous matter instead of it, occupying a portion or even the whole of 

 the sole and frog. It is the occasional consequence of bruise, puncture, corn, 

 quittor, and thrush, and is exceedingly difficult to cure. It is more frequently 

 the consequence of neglected thrush than of any other disease of the foot, or 

 rather it is thrush involving the frog, the bars, and the sole, and making the 

 foot in one mass of rank putrefaction. 



It is oftenest found in, and is almost peculiar to the heavy breed of cart horses, 

 and partly resulting from constitutional predisposition. Horses with white legs 

 and thick skins, and much hair upon their legs, the very character of many 

 dray horses, are subject to canker, especially if they have had an attack of 

 grease, or their heels are habitually thick and greasy. The disposition to can- 

 ker is certainly hereditary. The dray horse likewise has this disadvantage, that 

 in order to give him foot-hold, it is sometimes necessary to raise the heels, of the 

 hinder feet so high, that all pressure on the frog is taken away ; its functions are 

 destroyed, and it is rendered liable to disease. Canker, however, arises mostly 

 from the peculiar injury to which the feet of these horses are subject from the 

 enormous shoes with which they are covered the bulk of the nails with which 

 these shoes are fastened to the foot, the strain of the foot in the violent although 

 short exertion of moving heavy weights ; but, most of all, neglect of the feet 

 and the filthiness of the stable in these establishments. 



Although canker is a disease most difficult to remove, it is easily prevented. 

 Attention to the punctures to which these heavy horses, with their clubbed feet 

 and brittle hoofs, are more than any others subject in shoeing, and to the 



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