379 



THRUSH. 



Thrush is a disease characterized by an excessive secretion of un- 

 healthy matter from the cleft of the frog. While all classes of horses 

 are liable to this affection, it is more often seen in the common draft 

 horse than in any other breed, a fact due to the conditions of servitude 

 and not to the fault of the breed. Country horses are much less sub- 

 ject to tlie disease, except in wet, marshy districts, than are the horses 

 used in cities and towns. 



Causes. — The most common cause of thrush is the filthy condition of 

 the stable in which the animal is kept. Mares are more liable to contract 

 the disease in the hind feet when the- cause is due to filth, while the geld- 

 ing and stallion are more likely to develop it in the fore feet. Hard 

 work, on rough and stony roads, may also induce the disease, as may a 

 change from dryness to excessive moisture. The latter cause is often 

 seen to operate in old track horses, whose feet are constantly soaked in 

 the bath-tub for the purpose of relieving soreness. Muddy streets and 

 roads, especially where mineral substances are plentiful, excite this 

 abnormal condition of the frog. Contracted heels, scratches, and navic- 

 ular disease predispose to thrush, while by some a constitutional tend- 

 ency is believed to exist among certain animals which otherwise j)re- 

 sent a i)erfect frog. 



Symptoms. — At first there is simply an increased moisture in the cleft 

 of the frog, accompanied by an offensive smell. After a time a consider- 

 able discharge takes place— thin, watery, and highly offensive — chang- 

 ing gradually to a thicker puriform matter, which rapidly" destroys the 

 horn of the frog. Only in old and severe cases is the patient lame and 

 the foot feverish, — cases in which the whole frog is involved in the dis- 

 eased process. 



Treatment. — Thrushes are to be treated by cleanliness, the removal 

 of all exciting causes, and a return of the frog to its normal condition. 

 As a rule, the diseased and ragged portions of horn are to be pared 

 awa}', and the foot poulticed for a day or two with boiled turnips, to 

 which may be added a few drops of carbolic acid or a handful of pow- 

 dered charcoal to destroy the offensive smell. The cleft of the frog and 

 the grooves on the edges are then to be cleaned and well filled with dry 

 calomel, and the foot dressed with oakum and a roller bandage. If the 

 discharge is profuse the dressing should be changed daily, otherwise it 

 may be left on for two or three days at a time. Where a constitutional 

 taint is supposed to exist with swelling of the legs, grease, etc., a pur- 

 gative followed by dram doses of sulphate of iron, repeated daily, may 

 be prescribed. In cases where the growth of horn seems too slow, a 

 Spanish fly blister applietl to the heels is often followed by good re- 

 sults. Feet in which the disease is readily induced may be protected 

 in the stable with a leather boot. If the thrush is but a sequel to other 

 diseases a permanent cure may not be possible. 



