_Treatment._--This disease is so often the result of indigestion that a laxative of 1 pound Glauber's salt in 3 or 4 quarts water or 1-1/2 pints olive oil is often demanded to clear away irritants from the alimentary ca.n.a.l. Following this, in recent and acute cases, give 2 drams of acetate or bicarbonate of potash twice a day in the drinking water. If the bowels still become costive, give daily 1 ounce sulphate of soda and 20 grains of powdered nux vomica. In debilitated horses combine the nux vomica with one-half ounce powdered gentian root. As a wash for the skin use 1 dram bicarbonate of soda and 1 dram carbolic acid in a quart of water, after having cleansed the surface with tepid water. Employ the same precautions as regards feeding, stabling, and care of harness as in simple congestion of the skin.

In the more inveterate forms of eczema more active treatment is required. Soak the scabs in fresh sweet oil, and in a few hours remove these with tepid water and Castile soap; then apply an ointment of sulphur or iodid of sulphur day by day. If this seems to be losing its effect after a week, change for mercurial ointment or a solution of sulphid of pota.s.sium, or of hyposulphite of soda, 3 drams to the quart of water. In these cases the animal may take a course of sulphur (1 ounce daily), bisulphite of soda (one-half ounce daily), or of a.r.s.enic (5 grains daily) mixed with 1 dram bicarbonate of soda.

INFLAMMATION WITH PUSTULES.

In this affection the individual elevations on the inflamed skin show in the center a small sac of white, creamy pus, in place of the clear liquid of a blister. They vary in size from a millet seed to a hazelnut.

The pustules of glanders (farcy buds) are to be distinguished by the watery contents and the cordlike swelling, extending from the pustules along the line of the veins, and those of boils by the inflammation and sloughing out of a core of the true skin. The hair on the pustule stands erect, and is often shed with the scab which results. When itching is severe the parts become excoriated by rubbing, and, as in the other forms of skin disease, the character of the eruption may become indistinct. Old horses suffer mainly at the root of the mane and tail and about the heels, and suckling foals around the mouth, on the face, inside the thighs, and under the tail.

Pustules, like eczema, are especially liable to result from unwholesome feed and indigestion, from a sudden change of feed--above all, from dry to green. In foals it may result from overheating of the mare and allowing the first milk after she returns, or by milk rendered unwholesome by faulty feeding of the dam. If a foal is brought up by hand the souring and other decompositions in the milk derange the digestion and cause such eruption. Vetches and other plants affected with honeydew and buckwheat have been the cause of these eruptions on white portions of the skin. Disorders of the kidneys or liver are common causes of this affection.

_Treatment._--Apply soothing ointments, such as benzonated oxid of zinc, or vaseline with 1 dram oxid of zinc in each ounce. Or a wash of 1 dram sugar of lead or 2 drams hyposulphite of soda in a quart of water may be freely applied. If the skin is already abraded and scabby, smear thickly with vaseline for some hours, then wash with soapsuds and apply the above dressings. When the excoriations are indolent they may be painted with a solution of lunar caustic 2 grains to 1 ounce of distilled water.

Internally counteract costiveness and remove intestinal irritants by the same means as in eczema, and follow this with one-half ounce doses daily of hyposulphite of soda, and one-half ounce doses of gentian. Inveterate cases may often be benefited by a course of sulphur, bisulphite of soda, or a.r.s.enic. In all, the greatest care must be taken with regard to feed, feeding, watering, cleanliness, and work. In wet and cold seasons predisposed animals should, so far as possible, be protected from wet, mud, snow, and melted snow--above all, from that which has been melted by salt.

BOILS, OR FURUNCLES.

These may appear on any part of the skin, but are especially common on the lower parts of the limbs, and on the shoulders and back where the skin is irritated by acc.u.mulated secretion and chafing with the harness.

In other cases the cause is const.i.tutional, or attended with unwholesome diet and overwork with loss of general health and condition. They also follow on weakening diseases, notably strangles, in which irritants are retained in the system from overproduction of poisons and effete matter during fever, and imperfect elimination. There is also the presence of a pyogenic bacterium, by which the disease may be maintained and propagated.

While boils are pus producing, they differ from simple pustule in affecting the deepest layers of the true skin, and even the superficial layers of the connective tissues beneath, and in the death and sloughing out of the central part of the inflamed ma.s.s (core). The depth of the hard, indurated, painful swelling, and the formation of this central ma.s.s or core, which is bathed in pus and slowly separated from surrounding parts, serve to distinguish the boil alike from the pustule, from the farcy bud, and from a superficial abscess.

_Treatment._--To treat very painful boils a free incision with a lancet in two directions, followed by a dressing with one-half an ounce carbolic acid in a pint of water, bound on with cotton wool or lint, may cut them short. The more common course is to apply a warm poultice of linseed meal or wheat bran, and renew daily until the center of the boil softens, when it should be lanced and the core pressed out.

If the boil is smeared with a blistering ointment of Spanish flies and a poultice put over it, the formation of matter and separation of the core is often hastened. A mixture of sugar and soap laid on the boil is equally good. Cleanliness of the skin and the avoidance of all causes of irritation are important items, and a teaspoonful of bicarbonate of soda once or twice a day will sometimes a.s.sist in warding off a new crop.

NETTLERASH (SURFEIT, OR URTICARIA).

This is an eruption in the form of cutaneous nodules, in size from a hazelnut to a hickory nut, transient, with little disposition to the formation of either blister or pustule, and usually connected with shedding of the coat, sudden changes of weather, and unwholesomeness or sudden change in the feed. It is most frequent in the spring and in young and vigorous animals (good feeders). The swelling embraces the entire thickness of the skin and terminates by an abrupt margin in place of shading off into surrounding parts. When the individual swellings run together there are formed extensive patches of thickened integument.

These may appear on any part of the body, and may be general; the eyelids may be closed, the lips rendered immovable, or the nostrils so thickened that breathing becomes difficult and snuffling. It may be attended with constipation or diarrhea or by colicky pains. The eruption is sudden, the whole skin being sometimes covered in a few hours, and it may disappear with equal rapidity or persist for six or eight days.

_Treatment._--This consists in clearing out the bowels by 5 drams Barbados aloes, or 1 pound Glauber's salt, and follow the operation of these by daily doses of one-half ounce powdered gentian and 1 ounce Glauber's salt. A weak solution of alum may be applied to the swellings.

PITYRIASIS, OR SCALY SKIN DISEASE.

This affection is characterized by an excessive production and detachment of dry scales from the surface of the skin (dandruff). It is usually dependent on some fault in digestion and an imperfect secretion from the sebaceous glands and is most common in old horses with spare habit of body. Williams attributes it to feed rich in saccharine matter (carrots, turnips) and to the excretion of oxalic acid by the skin. He has found it in horses irregularly worked and well fed and advises the administration of pitch for a length of time and the avoidance of saccharine feed. Otherwise the horse may take a laxative followed by dram doses of carbonate of potash, and the affected parts may be bathed with soft, tepid water and smeared with an ointment made with vaseline and sulphur. In obstinate cases sulphur may be given daily in the feed.

PRURITUS, OR NERVOUS IRRITATION OF THE SKIN.

This is seen in horses fed to excess on grain and hay, kept in close stables, and worked irregularly. Though most common in summer, it is often severe in hot, close stables in winter. Pimples, vesicles, and abrasions may result, but as the itching is quite as severe on other parts of the skin, these may be the result of scratching merely. It is especially common and inveterate about the roots of the mane and tail.

_Treatment_ consists in a purgative (Glauber's salt, 1 pound), restricted, laxative diet, and a wash of water slightly soured with oil of vitriol and rendered sweet by carbolic acid. If obstinate, give daily 1 ounce of sulphur and 20 grains nux vomica. If the acid lotion fails, 2 drams carbonate of potash and 2 grains of cyanid of pota.s.sium in a quart of water will sometimes benefit. If from pinworms in the r.e.c.t.u.m, the itching of the tail may be remedied by an occasional injection of a quart of water in which chips of qua.s.sia wood have been steeped for 12 hours.

HERPES.

This name has been applied to a disease in which there is an eruption of minute vesicles in circular groups or cl.u.s.ters, with little tendency to burst, but rather to dry up into fine scabs. If the vesicles break, they exude a slight, gummy discharge which concretes into a small, hard scab.

It is apparently noncontagious and not appreciably connected with any disorder of internal organs. It sometimes accompanies or follows specific fevers, and is, on the whole, most frequent at the seasons of changing the coat--spring and autumn. It is seen on the lips and pastern, but may appear on any part of the body. The duration of the eruption is two weeks or even more, the tendency being to spontaneous recovery. The affected part is very irritable, causing a sensitiveness and a disposition to rub out of proportion to the extent of the eruption.

_Treatment._--It may be treated by oxid of zinc ointment, and to relieve the irritation a solution of opium or belladonna in water, or of sugar of lead or oil of peppermint. A course of bitters (one-half an ounce of Peruvian bark daily for a week) may be serviceable in bracing the system and producing an indisposition to the eruption.

BLEEDING SKIN ERUPTIONS, OR DERMATORRHAGIA PARASITICA.

In China, Hungary, Spain, and other countries horses frequently suffer from the presence of a threadworm (_Filaria haemorrhagica_ Railliet, _F.

multipapillosa_ Condamine and Drouilly) in the subcutaneous connective tissue, causing effusions of blood under the scurf skin and incrustations of dried blood on the surface. The eruptions, which appear mainly on the sides of the trunk, but may cover any part of the body, are rounded elevations about the size of a small pea, containing blood which bursts through the scurf skin and concretes like a reddish scab around the erect, rigid hairs. These swellings appear in groups, which remain out for several days, gradually diminishing in size; new groups appear after an interval of three or four weeks, the manifestation being confined to three or four months of spring and disappearing in winter. A horse will suffer for several years in succession and then permanently recover. A fatal issue is not unknown. To find the worm the hair is shaved from the part where the elevations are felt, and as soon as a bleeding point is shown the superficial layer is laid open with the knife, when the parasite will be seen drawing itself back into the parts beneath. The worm is about 2 inches long and like a stout thread, thicker toward the head than toward the tail, and with numerous little conical elevations (papillae) around the head. The young worms are numerous in the body of the adult female worm. The worm has become common in given localities, and probably enters the system with feed or water.

_Treatment_ is not satisfactory, but the affected surface should be kept clean by sponging, and the pressure of harness on any affected part must be avoided. Thus rest may become essential. The part may be frequently washed with a strong solution of pota.s.sium sulphid.

SUMMER SORES FROM FILARIA IRRITANS.

The summer sores of horses (dermat.i.tis granulosa, boils) have been traced to the presence in the skin of another parasite, 3 millimeters in length and extremely attenuated (_Filaria irritans_ Railliet). The sores may be seen as small as a millet seed, but more frequently the size of a pea, and may become an inch in diameter. They may appear on any point, but are especially obnoxious where the harness presses or on the lower parts of the limbs. They cause intense and insupportable itching, and the victim rubs and bites the part until extensive raw surfaces are produced. Aside from such friction the sore is covered by a brownish-red, soft, pulpy material with cracks or furrows filled with serous pus. In the midst of the softened ma.s.s are small, firm, rounded granulations, fibrinous, and even caseated, and when the soft, pultaceous material has been sc.r.a.ped off, the surface bears a resemblance to the fine, yellow points of miliary tuberculosis in the lung. The worm or its debris is found in the center of such ma.s.ses.

These sores are very obstinate, resisting treatment for months in summer, and even after apparent recovery during the cold season they may appear anew the following summer. In bad cases the rubbing and biting may cause exposure of synovial sacs and tendons, and cause irremediable injury. Even in winter, however, when the diseased process seems arrested, there remain the hard, firm, resistant patches of the skin with points in which the diseased product has become softened like cheese.

The apparent subsidence of the disease in winter is attributed to the coldness and comparative bloodlessness of the skin, whereas in summer, with high temperature, active circulation, and rapid cell growth, inflammation is increased, itching follows, and from the animal rubbing the part the irritation is persistently increased. The hotter the climate the more troublesome the disease.[4]

_Treatment_ consists, first, in placing the animal in a cool place and showering the surface with cold water. The parasite may be destroyed by rubbing the surface of the wound with iodoform and covering it with a layer of collodion, and repeating the applications very 24 hours for 15 days, or until the sores heal up. Ether or chloroform, poured on cotton wool and applied to the sore for two minutes before painting it with collodion, may be used in place of iodoform.[5]

CRACKED HEELS (SCRATCHES, OR CHAPS ON KNEE AND HOCK).

This usually sets in with swelling, heat, and tenderness of the hollow of the heel, with erections of the hairs and redness (in white skins), with stiffness and lameness, which may be extreme in irritable horses.

Soon slight cracks appear transversely, and may gain in depth and width, and may even suppurate. More frequently they become covered at the edges or throughout by firm incrustations resulting from the drying of the liquids thrown out, and the skin becomes increasingly thick and rigid. A similar condition occurs behind the knee and in front of the hock (malanders and salanders), and may extend from these points to the hoof, virtually incasing that side of the limb in a permanent incrusting sheath.

_Causes._--Besides a heavy lymphatic const.i.tution, which predisposes to this affection, the causes are overfeeding on grain, unwholesome fodder, close, hot, dirty stables, constant contact with dung and urine and their emanations, working in deep, irritant mud; above all, in limestone districts, irritation by dry limestones or sandy dust in dry weather on dirt roads; also cold drafts, snow, and freezing mud, washing the legs with caustic soap, wrapping the wet legs in thick woolen bandages which soak the skin and render it sensitive when exposed next day, clipping the heels, weak heart and circulation, natural or supervening on overwork, imperfect nourishment, impure air, lack of sunshine, chronic exhausting, or debilitating diseases, or functional or structural diseases of the heart, liver, or kidneys. These last induce dropsical swelling of the limbs (stocking), weaken the parts, and induce cracking.

Finally the cicatrix of a preexisting crack, weak, rigid, and unyielding, is liable to reopen under any severe exertion; hence rapid paces and heavy draft are active causes.

_Treatment._--In treatment the first step is to ascertain and remove the cause whenever possible. If there is much local heat and inflammation, a laxative (5 drams aloes or 1 pound Glauber's salt) may be given, and for the pampered animal the grain should be reduced or replaced altogether by bran mashes, flaxseed, and other laxative, nonstimulating feed. In the debilitated, on the other hand, nutritious food and bitter tonics may be given, and even a course of a.r.s.enic (5 grains a.r.s.enic with 1 dram bicarbonate of soda daily). When the legs swell, exercise on dry roads, hand rubbing, and evenly applied bandages are good, and mild astringents, like extract of witch-hazel, may be applied and the part subsequently rubbed dry and bandaged. If there is much heat but unbroken skin, a lotion of 2 drams sugar of lead to 1 quart of water may be applied on a thin bandage, covered in cold weather with a dry one. The same may be used after the cracks appear, or a solution of sulphurous acid 1 part, glycerin 1 part, and water 1 part, applied on cotton and well covered by a bandage. In case these should prove unsuitable to the particular case, the part may be smeared with vaseline 1 ounce, sugar of lead 1 dram, and carbolic acid 10 drops.

INFLAMMATION OF THE HEELS WITH SEBACEOUS SECRETION (GREASE, OR CANKER).

This is a specific affection of the heels of horses usually a.s.sociated with the growth of a parasitic fungus, an offensive discharge from the numerous sebaceous glands, and, in bad cases, the formation of red, raw excrescences (grapes) from the surface. It is to be distinguished (1) from simple inflammation in which the special fetid discharge and the tendency to the formation of "grapes" are absent; (2) from horsepox, in which the abundant exudate forms a firm, yellow incrustation around the roots of the hair, and is embedded at intervals in the pits formed by the individual pocks, and in which there is no vascular excrescence; (3) from foot scabies (mange), in which the presence of an acarus is distinctive; (4) from lymphangitis, in which the swelling appears suddenly, extending around the entire limb as high as the hock, and on the inner side of the thigh along the line of the vein to the groin, and in which there is active fever, and (5) from erysipelas, in which there is active fever (wanting in grease), the implication of the deeper layers of the skin and of the parts beneath giving a boggy feeling to the parts, the absence of the fetid, greasy discharge, and finally a tendency to form pus loosely in the tissues without any limiting membrane, as in abscess. Another distinctive feature of grease is its tendency to implicate the skin which secretes the bulbs or heels of the h.o.r.n.y frog and in the cleft of the frog, const.i.tuting the disease known as canker.

_Causes._--The predisposing causes of grease are essentially the same as those of simple inflammation of the heel, so that the reader may consult the preceding section. Though a specific fungus and bacteria of different kinds are present, they tend mainly to aggravation of the disease, and are not proved to be essential factors in causation.

_Symptoms._--The symptoms vary according to whether the disease comes on suddenly or more tardily. In the first case there is a sudden swelling of the skin in the heel, with heat, tenderness, itching, and stiffness, which is lessened during exercise. In the slower forms there is seen only a slight swelling after rest, and with little heat or inflammation for a week or more. Even at this early stage, a slight, serous oozing may be detected. As the swelling increases, extending up toward the hock or knees, the hairs stand erect, and are bedewed by moisture no longer clear and odorless, but grayish, milky, and fetid. The fetor of the discharge draws attention to the part whenever one enters the stable, and the swollen pastern and wet, matted hairs on the heel draw attention to the seat of the malady. If actively treated, the disease may not advance further, but if neglected the tense, tender skin cracks open, leaving open sores from which vascular bleeding growths grow up, const.i.tuting the "grapes." The hair is shed, and the heel may appear but as one ma.s.s of rounded, red, angry excrescences which bleed on handling and are covered with the now repulsively fetid, decomposing discharge. During this time there is little or no fever, the animal feeds well, and but for its local trouble it might continue at work.

When the malady extends to the frog, there is a fetid discharge from its cleft or from the depressions at its sides, and this gradually extends to its whole surface and upon the adjacent parts of the sole. The horn meanwhile becomes soft, whitish, and fleshy in aspect, its const.i.tuent tubes being greatly enlarged and losing their natural cohesion; it grows rapidly above the level of the surrounding horn, and when pared is found to be penetrated to an unusual depth by the secreting papillae, and that at intervals these have bulged out into a vascular fungous ma.s.s comparable to the "grapes."

_Treatment._--In treatment hygienic measures occupy a front rank, but are in themselves insufficient to establish a cure. All local and general conditions which favor the production and persistence of the disease must be guarded against. Above all, cleanliness and purity of the stable and air must be obtained; also nourishing diet, regular exercise, and the avoidance of local irritants--septic, muddy, chilling, etc. At the outset benzoated oxid of zinc ointment may be used with advantage. A still better dressing is made with 1 ounce vaseline, 2 drams oxid of zinc, and 20 drops iodized phenol. If the surface is much swollen and tender, a flaxseed poultice may be applied, over the surface of which has been poured some of the following lotion: Sugar of lead, one-half ounce; carbolic acid, 1 dram; water, 1 quart. All the astringents of the pharmacopoeia have been employed with more or less advantage, and some particular one seems to suit particular cases or patients. To destroy the grapes, they may be rubbed daily with strong caustics (copperas, bluestone, lunar caustic), or each may be tied round its neck with a stout, waxed thread, or, finally and more speedily, they may be cut off by a black-smith's shovel heated to redness and applied with its sharp edge toward the neck of the excrescence, over a cold shovel held between it and the skin to protect the skin from the heat.

The cold shovel must be kept cool by frequent dipping in water. After the removal of the grapes the astringent dressing must be persistently applied to the surface. When the frog is affected, it must be pared to the quick and dressed with dry caustic powders (quicklime, copperas, bluestone) or carbolic acid and subjected to pressure, the dressing being renewed every day at least.

ERYSIPELAS.