DISEASES OF HORSES 297 



merge in part or in whole into a papular, vesicular, or pustular 

 eruption. 



Erythema may arise from a variety of causes, and is often 

 named in accordance with its most prominent cause. Thus the 

 chilling, or partial freezing, of a part will give rise to a severe 

 reaction and congestion. When snowy or icy streets have been 

 salted this may extend to severe inflammation with vesicles, pus- 

 tules, or even sloughs of circumscribed portions of the skin of the 

 pastern (chilblain, frostbite). Heat and burning have a similar 

 effect, and this often comes from exposure to the direct rays of the 

 sun. The skin that does not perspire is the most subject, and hence 

 the white face or white limb of a horse becoming dried by the in- 

 tensity of the sun's rays often suffers to the exclusion of the rest 

 of the body (white face and foot disease). The febrile state of the 

 general system is also a potent cause, hence the white-skinned horse 

 is rendered the more liable if kept on a heating ration of buck- 

 wheat, or even of wheat or maize. Contact of the skin with oil of 

 turpentine or other essential oils, with irritant liquids, vegetable or 

 mineral, with rancid fats, with the acrid secretions of certain ani- 

 mals, like the irritating toad, with pus, sweat, tears, urine, or liquid 

 feces, will produce congestion or even inflammation. Chafing is a 

 common cause, and is especially liable to affect the fat horse be- 

 tween the thighs, by the side of the sheath or scrotum, on the inner 

 side of the elbow, or where the harness chafes on the poll, shoulder, 

 back, breastbone, and under the tail. The accumulation of sweat 

 and dust between the folds of the skin and on the surface of the 

 harness, and the specially acrid character of the sweat in certain 

 horses contribute to chafing or intertrigo. The heels often become 

 congested, owing to the irritation caused by the short bristly hairs 

 in clipped heels. Again, congestion may occur from friction by 

 halter, harness, or other foreign body under the pastern, or inside 

 the thigh or arm, or by reason of blows from another foot. Finally 

 erythema is especially liable to occur in spring when the coat is 

 being shed, and the hair follicles and general surface are exposed 

 and irritable in connection with the dropping of the hairs. 



If due only to a local irritant, congestion will usually disappear 

 when such cause has been removed, but when the feeding or sys- 

 tem is at fault these conditions must be first corrected. While the 

 coat is being shed the susceptibility will continue, and the aim 

 should be to prevent the disease developing and advancing so as to 

 weaken the skin, render the susceptibility permanent, and lay the 

 foundation of persistent or frequently recurring skin disease. Hence 

 at such times the diet should be nonstimulating; any excess of 

 grain, and above all of buckwheat, Indian corn, or wheat, being 

 avoided. A large grain ration should not be given at once on return 

 from hard work, when the general system and stomach are unable 

 to cope with it ; the animal should not be given more than a swallow 

 or two of cold water when perspiring and fatigued; nor should he 

 be allowed a full supply of water just after his grain ration ; ho 

 should not be overheated or exhausted by work, nor should dried 



