Part 42

=Abnormal respiratory sounds= are marked symptoms in the advanced stages. The wheezing noise of the breathing, especially when that is excited by exertion, may be heard at a short distance from the animal. The increased resonance on percussion along the lower border of the lung is only heard when the emphysema is extensive. The dry sibilant or whistling râle heard over the same parts is equally a symptom of the advanced stages. When there is much discharge a moist rattle is often heard over the lower end of the windpipe or immediately behind the middle of the shoulder. The overlaying of the anterior lobe by the thick, muscular shoulder, and the complication of results obtained at the free border of the lung by the abdominal noises and resonance render these results less conclusive in the earlier stages and slighter cases.

The application of the hand to the side of the chest behind the left elbow may detect a strong impulse of the heart with each beat. If the patient is actively exercised for some time this may be felt on the right side as well. This symptom indicates the existence of dilatation of the right cavities of the heart.

The symptoms of =indigestion= are also very manifest. The dung passed is like so much chopped hay and oats, and does not at all resemble the fæces of a healthy horse. The abdomen is tumid, tense and filled with flatus, which is frequently passed per-ano, and has no doubt given rise to the name of =broken wind=. This expulsion of gas from the rectum usually takes place whenever the animal is excited to cough. When first started on a journey, the frequent passage of wind and dung for the first mile or two is one of the most disagreeable features of the disease. When the animal has thus emptied himself he usually goes much better for the remainder of the journey.

Broken-winded horses are always greedy feeders, and if they get little work they manage to maintain their flesh. But they are soft and flabby, and if put to active work they fall off rapidly, becoming emaciated and hidebound, a true indication of their impaired digestion.

The symptoms are liable to occasional aggravation. If the stomach and bowels are overloaded they are invariably so. If the patient is kept in a hot, close stable, the same result follows. Thick, muggy weather has the same effect. After a more than usually severe day’s work all the symptoms may be intensified, and this may continue for several days or a week. Bouley attributes this to an extensive rupture of air cells and a sudden increase of emphysema, and the gradual subsidence of the symptoms to the partial absorption of the displaced air and the accommodation of the lung to its new condition.

Light and laxative diet on the other hand alleviates the symptoms and a broken winded horse usually improves at grass.

Course. The general tendency of broken wind is to persistent aggravation, but by a judicious regimen many cases may be checked in their progress and greatly relieved, or even cured.

Treatment. We have already seen that broken wind is virtually unknown on natural pastures where the grass is short, green and succulent. Turning out on such pastures will improve or even temporarily cure mild cases. The same may be said of the laxative systems of diet. (See that recommended for chronic bronchitis). Feeding on dry grain only, with a very limited supply of water, will enable many broken winded horses to do ordinary work with comparative ease and comfort. In such cases, however, improvement is only due to the empty and unclogged condition of the digestive organs and the symptoms return with all their former intensity when the original diet is restored. By way of palliation much may be secured by avoiding accidental causes of aggravation. If catarrh or bronchitis has supervened it should be treated in the ordinary way. If the stomach and bowels are overloaded and costive, a small dose of aloes and enemata will relieve. If the stable is close a free admission of air will be beneficial. The temporary excitement in these cases may be further alleviated by sedatives, of which opium and digitalis have been mostly employed. The last agent will sometimes control the breathing to such an extent that the horse may be thought to have completely recovered. Professor Dick believed that he had effected a cure in one case by the administration at a single dose of a drachm each of camphor, opium, calomel and digitalis. Temporary results only can, however, be expected from such agents, except in the case of an aggravation due to a cause acting for a limited time only, in which case the partial improvement may be lasting.

By adopting such measures to check accidental complications and confining the animal to a rigid system of diet a broken winded horse may be worked with comfort to himself and his master. The aliment should be principally or exclusively of oats, bran or barley, though good succulent grass, turnips, carrots, beet, and potatoes may be allowed, as may also wheat or oat straw in limited quantity, but no hay and above all none prepared from red clover, alfalfa, sainfoin, or allied foreign plants and none that is musty or otherwise injured by keeping. No food nor water must be allowed for one or two hours before going to work, and the pace must be slow at first and gradually increased as the horse empties himself, and the breathing gets less embarrassed. If meadow hay, straw or other bulky food is allowed in small quantity this must be after the horse has returned from his day’s work.

If the food above recommended is boiled or pulped, and mixed with some saccharine agent as molasses its restorative action is enhanced.

If, however, we add to these hygienic and dietetic measures a prolonged course of arsenic, the symptoms generally disappear. From five to fifteen grains of arsenic made into a powder with a drachm of bicarbonate of soda may be given daily in the food until improvement is noticed or symptoms of the poisonous action of the agent appear. When these are manifested in loss of appetite, colicy pains or red and watery eyes the medicine must be suspended and begun again some days later in smaller doses.

The therapeutic value of arsenic in this case is probably largely due to its action on the nervous system, which has long been recognized. As early as the first century of the Christian Era, Dioscorides, recommended its use in asthma and in recent times it has acquired a considerable reputation for the treatment of neuralgia. Another—though perhaps an allied—physiological action of arsenic no doubt adds to its value in this equine disorder. This is its power of retarding the waste of tissues. This property it possesses in common with tea, coffee and some other agents, but to a greater degree. This has led to its extensive employment by the peasants in Lower Austria, Styria, and the mountains separating Austria from Hungary, who found that it improved their personal appearance, increased their weight and enabled them to sustain greater exertions in climbing without fatigue. It was the revelations of Dr. Tschudi concerning the Styrian arsenic eaters that first led Professor Bouley to try this agent in broken wind.

=Examination of Broken-winded Horses.= Though the symptoms enumerated above are sufficient to detect broken wind in all ordinary cases, yet it may not be time thrown away to caution the reader against pronouncing it absent when the more prominent symptoms are not seen. Unscrupulous dealers do not hesitate to avail of a variety of devices to conceal the symptoms and make the animal pass for a sound horse. Digitalis and other sedatives are so employed, but are mostly rejected because they render the horse dull and sluggish. By some the bowels are unloaded by a dose of physic, the horse is kept on a spare diet of oats, beans and other grain, water is withheld, and on the morning of sale one or two pounds of leaden shot or of bacon fat are administered. The inconvenience attendant on the presence of these agents in the stomach makes the animal desist as much as possible from moving the abdominal organs, and the double lifting of the flank is thus more or less completely hidden. With the veterinarian however this measure like the last defeats its own purpose, for such horses are always intolerably thirsty and if allowed to regale themselves at the nearest watering trough, the charm is broken, the double lift returns and with it all the symptoms of the malady.

A brutal practice existed among ancient farriers, of making an artificial opening into the rectum to allow the exit of the flatus upon which they conceived the disease to depend. This was effected either by cutting through the sphinctor ani with a knife or by making a new opening to one side of it with a red hot iron. According to Ferguson this has been improved upon by the modern Irish jockey, in the case of broken winded mares. With the knife an artificial communication is made between the rectum and the vagina, of sufficient size to insure that it will remain open and large enough to allow pellets of dung to pass into the vagina. The double lifting of the flank forces the fæces through this artificial opening, and to avoid the inconvenience of their presence in the vagina the animal carefully refrains from this action. This orifice further allows the free escape of any gases generated in the rectum and thus materially relieves the flatulence. Ferguson says he has seen broken winded mares that have been operated on in this manner, that breathed so freely that even professional men have failed to detect the affection.

In all cases of broken wind, no matter how masked there will be manifest, on slight exertion, a permanent dilatation of the nostrils—i.e., alike in inspiration and expiration,—and when any such suspicious symptom is seen the horse should be carefully examined, especially the state of his lungs as ascertained by auscultation and percussion, his breathing after he has freely partaken of water and hay, and, if there is suspicion of drugging, after he has stood over night in a hot stable plentifully supplied with both hay and water.

It should be borne in mind that mares advanced in pregnancy often show no double action of the flank though decidedly broken winded.

POLYPUS OF THE BRONCHIAL TUBES.

Like other mucous membranes, that covering the bronchial tubes, is liable to diseased growths, which may each remain attached by a broad base, and form a morbid elevation of the surface, or it may become loosened and retain its connection with the mucous membrane only by a neck or pedicle. An interesting case of the latter variety is recorded in the Edinburgh Veterinary Review for January, 1864, by Mr. Parker of Birmingham. It was attached to the wall of the right bronchus about an inch below the bifurcation of the trachea, and had an ovoid form measuring 8½ inches in its longest circumference by 4½ in its shorter. The pedicle was 1½ inch long and allowed the tumor to pass freely upward into the lower part of the windpipe, threatening instant suffocation. It had a fibrous structure and was continuous with the interlacing bundles of yellow elastic tissues which cover the cartilaginous rings of the bronchus.

From its frequent displacement upward the tumor gave rise to paroxysms of hurried and difficult breathing apparently threatening suffocation, but when these passed off, respiration was tolerably tranquil and easy. The fits of dyspnœa came on after any unwonted excitement, but above all after a cough. In such cases the tumor had been coughed up into the lower end of the windpipe and until it slid back into its former position, the animal seemed on the very verge of death. The paroxysms had appeared very frequently during a period of five months that had elapsed since her purchase, increasing steadily in severity and finally causing death. The lungs contained many small abscesses the result doubtless of the frequent paroxysms of dyspnœa.

Cases of this kind are not usually amenable to treatment, nevertheless as they are pretty certain to end fatally if neglected, it would be quite permissible to perform tracheotomy in the lower part of the neck and attempt to snare the tumor with an elastic wire passed through a single or double tube. The tumor might even be seized by a vulsella and twisted off, provided it could be reached.

DISEASES OF THE BRONCHIAL AND MESENTERIC GLANDS.

These are the seat of congestions, neoplasms, and parasites, including pentastoma, actinomycosis, tubercle, glanders, etc., which will be treated under their respective headings.

PARASITES OF THE AIR PASSAGES, LUNGS, AND PLEURA.

Nearly all the domestic animals are subject to parasites of the lower air passages. These give rise to verminous bronchitis in cattle, sheep, horses, swine, goats and camels, to gapes in birds, and to pulmonary acariasis in fowls. The lungs and pleura are invaded by distomum, echinococcus, cysticercus, aspergillus, etc. (See parasites).

DISEASES OF THE HEART AND ORGANS OF CIRCULATION.

Susceptibility in different genera. Reasons for partial immunity of the quadruped, special and general causes in quadrupeds, violent, forced work, fatty degeneration, swallowing of pointed metallic bodies, difficult diagnosis in the animal. Position of the heart in the horse, ox, sheep, pig, carnivora, birds. Structure of the heart as a pump. Results of imperfect structure or action. Heart walls. Table of size of the heart. Capacity. Weight. Pulse in each healthy genus, according to age, size, environment, temperament, proximity to parturition. Morbid conditions of the pulse, frequent, slow, quick, tardy, full, strong, weak, feeble, indistinct, small, hard, wiry, thready, oppressed, leaping and receding, intermittent, unequal, irregular, anæmic, venous. Percussion. Palpitation. Auscultation. Healthy sounds. Morbid sounds, in unusual place, force, intensity, rythm, repetition of 1st sound, of 2nd sound. Murmurs, synchronance with given stages of heart movement, their significance, pericardial murmur. General symptoms of heart disease, cold extremities, passive congestions, dropsies of limbs, etc., shortness of breath, venous pulse, vertigo, dulness, sluggishness, corpulence.

The lower animals are perhaps less subject to heart disease than mankind, but the comparative immunity generally assumed for them is far from being a real one. The horizontal position of the quadruped largely obviates that special tax upon the heart demanded by the erect position of man, and especially by the elevated place given to his more ample and vascular brain. Animals too are comparatively free from those mental and moral influences which so largely affect the regularity of the circulation in the human subject. But on the other hand many physical causes of heart disease affect the lower creation equally with their lord, while some undoubtedly operate with special force on the brute. All animals are subject to diseases of the heart as of other internal organs, from exposure; this organ is occasionally involved from its contiguity with other diseased structures or from interdependence of function as we have already seen in certain diseases of the lungs (congestion, broken wind, etc.); the tendency to heart disease frequently runs in a particular family of animals, especially with the rheumatic constitution, which is transmitted from parent to offspring as surely as the color of the skin the turn of the horn or the depth and spring of the rib. The lower animals are further subject to congenital malformations and imperfections and to deposits of morbid material around the heart or in its substance so as to impair its healthy action.

Horses and dogs have special predisposing causes in the violent and prolonged exertion to which they are habitually exposed. The quiet sluggish and nonexcitable ox and pig meet with dangers no less real though of a different kind in the overfeeding which induces fatty degeneration of the heart as of other muscular tissues. The larger ruminants are further endangered by their propensity to swallow needles and other sharp pointed bodies which ultimately reach and penetrate the heart.