Chapter V: Part 5

The severity of a hemorrhage depends upon the size of the vessel from which the blood escapes, though it may be stated that it is more serious when arteries are severed. If the wound in an artery is in the direction of its length, the blood escapes more freely than if the vessel is completely severed, because in the latter instance the severed ends retract, curl in, and may aid very much in arresting the flow. When the blood merely oozes from the wound, and even when it flows in a small stream, the forming of the clot arrests the hemorrhage in a comparatively short time.

Slight hemorrhages may be checked by the continuous application of cold water, ice, or snow, to the wound, as cold causes contraction of the small vessels. Water from a hose may be thrown on a wound, or dashed on it from the hand or a cup, or folds of cotton cloths may be held on it and kept wet. Ice or snow may be held against the wound, or they may be put into a bag and conveniently secured in position.

Hot water of an average temperature of 115∞ to 120∞ F. injected into the vagina or womb is often efficient in arresting hemorrhages from those organs. Tow, raw cotton, lint, or sponges may be forced into a wound and held or bound there with bandages. This is an excellent method of checking the flow of blood until the arrival of an expert. If the flow persists, these articles may be saturated with tincture of iron, but it is not advisable to use it unless necessary, as it is a caustic and retards healing by causing a slough. In cases of necessity, the articles may be saturated with vinegar, or tannic acid or alum dissolved in water may be used instead. Whatever article is used should be left in the wound sufficiently long to make sure that its removal will not be followed by a renewal of the hemorrhage. Sometimes it must remain there one or two days.

An iron heated white and then pressed on the bleeding vessel for three or four seconds is occasionally used. It should not be applied longer, or else the charred tissue will come away with the iron and thus defeat the purpose of its application.

Compression may be applied in different ways, but only the most convenient will be mentioned. To many wounds bandages may easily be applied. The bandages may be made of linen, muslin, etc., sufficiently wide and long, according to the nature of the wound and the region to be bandaged. Bed sheets torn in strips the full length make excellent bandages for this purpose. Cotton batting, tow, or a piece of sponge may be placed on the wound and firmly bound there with the bandages.

Many cases require ligating, which is almost entirely confined to arteries. A ligature is a piece of thread or string tied around the vessel. Veins are not ligated unless very large (and even then only when other means are not available) on account of the danger of causing phlebitis, or inflammation of a vein. The ligature is tied around the end of the artery, but in some instances this is difficult and it is necessary to include some of the adjacent tissue, although care should be taken not to include a nerve. To apply a ligature, it is necessary to have artery forceps (tweezers or small pincers may suffice) by which to draw out the artery in order to tie the string around it. To grasp the vessel it may be necessary to sponge the blood from the wound so that the end will be exposed. In case the end of the bleeding artery has retracted, a sharp-pointed hook, called a tenaculum, is used to draw it out far enough to tie. The ligature should be drawn tightly, so that the middle and internal coats will be cut through.

Another method of checking hemorrhage is called torsion. It consists in catching the end of the bleeding vessel, drawing it out a little, and then twisting it around a few times with the forceps, which lacerates the internal coats so that a check is effected. This is very effectual in small vessels, and is to be preferred to ligatures, because it leaves no foreign body in the wound. A needle or pin may be stuck through the edges of the wound and a string passed around between the free ends and the skin (Pl. XXVII, fig. 10), or it may be passed around in the form of a figure 8, as is often done in the operation of bleeding from the jugular vein.

ANEURISM.

A circumscribed dilatation of an artery, constituting a tumor which pulsates synchronously with the beats of the heart, is called aneurism. It is caused by disease and rupture of one or two of the arterial coats. The true aneurism communicates with the interior of the artery and contains coagulated blood. It is so deeply seated in cattle that treatment is out of the question. Such abnormalities are ascribable to severe exertion, to old age, to fatty or calcareous degeneration, or to parasites in the blood vessels. Death is sudden when caused by the rupture of an aneurism of a large artery, owing to internal hemorrhage. Sometimes spontaneous recovery occurs. As a rule no symptoms are caused in cattle by the presence of deep-seated aneurisms, and their presence is not known until after death.

A false aneurism results from blood escaping from a wounded artery into the adjacent tissue, where it clots, and the wound, remaining open in the artery, causes pulsation in the tumor.

THROMBOSIS (OBSTRUCTION) OF THE ARTERIES.

Arteries become obstructed as a result of wounds and other injuries to them, as those caused by the formation of an abscess or the extension of inflammation from surrounding structures to the coats of an artery. Arteries are also obstructed by the breaking off of particles of a plug or clot, partly obstructing the aorta or other large artery. These small pieces (emboli) are floated to an artery that is too small to permit them to pass and are there securely held, producing obstruction. These obstructions are shown by loss of power in the muscles supplied by the obstructed artery and by excitation of the heart and by respiration after exercise. The loss of power may not come into evidence until after exercise.

_Symptoms._--While standing still or when walking slowly the animal may appear to be normal, but after more active exercise a group of muscles, a leg, or both hind legs, may be handled with difficulty, causing lameness, and later there is practically a local paralysis. These symptoms disappear with rest. In some cases the collateral circulation develops in time, so that the parts receive sufficient blood and the symptoms disappear.

INFLAMMATION OF VEINS (PHLEBITIS).

When bleeding is performed without proper care or with an unclean lancet, inflammation of the vein may result, or it may be caused by the animal rubbing the wound against some object. When inflammation follows the operation, the coats of the vein become so much enlarged that the vessel may be felt hard and knotted beneath the skin, and pressure produces pain. A thin, watery discharge, tinged with blood, issues from the wound. The blood becomes coagulated in the vessel. In inflammation of the jugular the coagulation extends from the wound upward to the first large branch. Abscesses may form along the course of the vein. The inflammation is followed by obliteration of that part in which coagulation exists. This is of small import, as cattle have an accessory jugular vein which gradually enlarges and accommodates itself to the increased quantity of blood it must carry.

_Treatment._--The treatment for inflammation of the vein is to clip the hair from along the course of the affected vessel and apply a blister, the cerate of cantharides. Abscesses should be opened as soon as they form, because there is a possibility of the pus getting into the circulation.

In the operation of bleeding the instruments should be clean and free from rust. If the skin is not sufficiently opened, or when closing the wound the skin is drawn out too much, blood may accumulate in the tissue, and if it does it should be removed by pressing absorbent cotton or a sponge on the part. Care should also be used in opening the vein, so that the instrument may not pass entirely through both sides of the vein and open the artery beneath it.

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DISEASES OF THE HEART, BLOOD VESSELS, AND LYMPHATICS.

DESCRIPTION OF PLATE.

PLATE VII:

Diagram illustrating the circulation of the blood. The arrows indicate the direction in which the blood flows. The valves of the heart, situated between the right auricle and ventricle, and left auricle and ventricle, and between the ventricles and large arteries, are represented by curved lines. These valves are intended to prevent the flow of blood in a direction contrary to that indicated by the arrows.

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NONCONTAGIOUS DISEASES OF THE ORGANS OF RESPIRATION.

By WILLIAM HERBERT LOWE, D. V. S.

DIAGNOSIS.

In the determination of disease in the human being the physician, in making his diagnosis, is aided by both subjective and objective symptoms, but the veterinary physician, in a very large majority of cases, is obliged to rely almost solely upon objective symptoms, and perhaps in no class of diseases is this more true than in the exploration of those under consideration. This condition of affairs has a strong tendency to develop observation and discernment in the veterinarian, and not infrequently do we find that the successful veterinary practitioner is a very accurate diagnostician. In order to make a differential diagnosis, however, it is not only necessary to know the structure and functions of the organs in health, but to adopt a rigid system of details of examination, without which successful results can not be reached.

_History._--The history of a case should always be ascertained so far as possible. The information obtained is sometimes unsatisfactory and not to be depended upon, but even when this is the case it is advisable to weigh the evidence from every point of view.

In connection with the history of every case it is always of primary importance to ascertain the cause of illness. A knowledge of the origin and development of a disease is important, both in making a diagnosis and in formulating the treatment. Exposure to cold and dampness is frequently the exciting cause of affections of the organs of respiration.

The experienced practitioner is always sure to ascertain whether the particular animal he is called on to attend is the only one in the stable or on the premises that is similarly affected. If several animals are similarly affected, the disease may have a common cause, which may or may not be of an infectious nature.

Another thing that the experienced practitioner ascertains is what previous treatment, if any, the animal has had. Medicine given in excessive doses sometimes produces symptoms resembling those of disease.

The hygienic and sanitary conditions must always be considered in connection with the cause as well as the treatment of disease. Much of the disease which occurs in large dairies and elsewhere could be prevented if owners and those in charge of animals had proper regard for the fundamental laws of animal hygiene and modern sanitation. Disregard for these laws is the cause of most of the diseases under consideration in this chapter.

_Attitude and general condition._--The feeling of pain in animals suffering from serious affections of the organs of respiration is expressed to the close observer in no uncertain language--by their flinching when the painful part is touched; by the care with which they move or lie down; by walking or standing to "favor" the part; by the general attitude and expression of the eye; by the distress and suffering apparent in the face; and by other evidences.

The general physical condition and attitude of the sick animal tell the careful observer much that aids him in making a diagnosis and prognosis. Cows suffering from affections of the organs of respiration usually assume a position or attitude that is characteristic, well known to experienced stockmen, as well as to veterinarians. When an animal has a fever or is suffering from an inflammation, the skin is one of the first parts to undergo a change that is apparent to the average observer, for it soon loses its elasticity and tone, and the hair becomes dry and staring.

From the general condition or state of nutrition one is able to judge the effect that the disease has already had upon the animal and to estimate the strength remaining available for its restoration to health; from the degree of emaciation one can approximate the length of time the animal has been ill. The age and breed of the animal, as well as its constitution and temperament, are among the things that have to be taken into account in making a diagnosis and in overcoming the disease.

_The mucous membrane._--The mucous membrane should in all cases be examined. It can be readily seen by everting the eyelids or by an inspection of the lining membrane of the nostrils.

Paleness of the mucous membrane indicates weak circulation or poor blood and may result from disease, hemorrhage, or from inappropriate feed.

In healthy animals increased redness of the mucous membrane occurs from pain, excitement, or severe exertion, and in such instances is always transitory. In certain pathological conditions, such as fevers and inflammation, this condition of the mucous membrane will also be found. The increased redness of the mucous membrane lasts during the duration of the fever or inflammation.

A bluish or blue mucous membrane indicates that the blood is imperfectly oxidized and contains an excess of carbon dioxid, and is seen in serious diseases of the respiratory tract, such as pneumonia, and in heart failure.

_The secretions._--The secretions may be diminished, increased, or perverted. In the early stage of an inflammation of a secretory organ its secretion is diminished. In the early stage of pleurisy the serous membrane is dry, and as the disease advances the membrane becomes unnaturally moist. The products of secretion are sometimes greatly changed in character from the secretion in health, becoming excessively irritant and yielding evidence of chemical and other alterations in the character of the secretion.

_Cough._--Cough depends upon a reflex nervous action and may be primary when the irritation exists in the lungs or air passages, or secondary when caused by irritation of the stomach, intestines, or other parts having nervous communications with the respiratory apparatus. A cough is said to be dry, moist, harsh, hollow, difficult, paroxysmal, suppressed, sympathetic, etc., according to its character. It is a very important symptom, often being diagnostic in diseases of the respiratory organs, but this is a subject, however, which can be more satisfactorily treated in connection with the special diseases of the organs in question.

_Respiration._--In making an examination of an animal observe the depth, frequency, quickness, facility, and the nature of the respiratory movements. They may be quick or slow, frequent or infrequent, deep or imperfect, labored, unequal, irregular, etc., each of which indications has its significance to the experienced veterinarian.

Sleep, rumination, pregnancy in cows, etc., modify the respiratory movements even in health. Respiration consists of two acts--inspiration and expiration. The function of respiration is to take in oxygen from the atmospheric air, which is essential for the maintenance of life, and to exhale the deleterious gas known as "carbon dioxid."

The frequency of the respiratory movements is determined by observing the motions of the nostrils or of the flanks. The normal rate of respiration for a healthy animal of the bovine species is from 15 to 18 times a minute. The extent of the respiratory system renders it liable to become affected by contiguity to many parts and its nervous connections are very important.

Rapid, irregular, or difficult breathing is known as dyspnea, and in all such cases the animal has difficulty in obtaining as much oxygen as it requires. Among the conditions that give rise to dyspnea may be mentioned restricted area of active lung tissue, owing to the filling of portions of the lungs with inflammatory exudate, as in pneumonia; painful movements of the chest, as in rheumatism or pleurisy; fluid in the chest cavity, as in hydrothorax; adhesions between the lungs and chest walls; compression of the lungs or loss of elasticity; excess of carbon dioxid in the blood; weakness of the respiratory passages; tumors of the nose and paralysis of the throat; swellings of the throat; foreign bodies and constriction of the air passages leading to the lungs; fevers, etc.

As already stated, it is only the careful and constant examination of animals in health that will enable one properly to appreciate abnormal conditions. One must become familiar with the frequency and character of the pulse and of the respirations and know the temperature of the animal in health, before changes in abnormal conditions can be properly appreciated.

_Temperature._--The temperature should be taken in all cases of sickness. Experienced practitioners can approximate the patient's temperature with remarkable accuracy, but I strongly recommend the use of the self-registering clinical thermometer, which is a most valuable instrument in diagnosing diseases. (See Pl. III, fig. 1.) It is advisable to get a tested instrument, as some thermometers in the market are inaccurate and misleading. The proper place to insert the thermometer is in the rectum, where the instrument should be rested against the walls of the cavity for about three minutes. The normal temperature of the bovine is 101∞ to 102∞ F., which is higher than that of the horse. A cow breathes faster, her heart beats faster, and her internal temperature is higher than that of the horse. Ordinary physiological influences--such as exercise, digestion, etc.--give rise to slight variations of internal temperature; but if the temperature rises two or three degrees above the normal some diseased condition is indicated.

_Pulse._--The pulse in a grown animal of the bovine species in a state of good health beats from 45 to 55 times a minute. Exercise, fright, fear, excitement, overfeeding, pregnancy, and other conditions aside from disease may affect the frequency and character of the pulse. It assumes various characters according to its rapidity of beat, frequency of occurrence, resistance to pressure, regularity, and perceptibility. Thus we have the quick or slow, frequent or infrequent, hard or soft, full or imperceptible, large or small pulse, the character of each of which may be determined from its name; also that known as the intermittent, either regular or irregular. We may have a dicrotic, or double, pulse; a thready pulse, which is extremely small and scarcely perceptible; the venous, or jugular, pulse; the "running down" pulse, and so on. (See p. 76.)

In cattle the pulse is conveniently felt over the submaxillary artery where it winds around the lower jawbone, just at the lower edge of the flat muscle on the side of the cheek. If the cow is lying down the pulse may be taken from the metacarpal artery on the back part of the fore fetlock. The pulsations can be felt from any superficial artery, but in order to ascertain the peculiarities it is necessary to select an artery that may be pressed against a bone.

There is a marked difference in the normal or physiological pulse of the horse and that of the cow, that of the horse being full and rather tense, while in the cow it is soft and rolling. The pulse is faster in young or old cattle than it is in those of middle age.

_Auscultation._--Auscultation and percussion are the chief methods used to determine the various pathological changes that occur in the respiratory organs. Auscultation is the act of listening, and may be either mediate or immediate. Mediate auscultation is accomplished by aid of an instrument known as the stethoscope, one extremity of which is applied to the ear and the other to the chest of the animal. In immediate auscultation the ear is applied directly to the part. Immediate auscultation will answer in a large majority of cases. Auscultation is resorted to in cardiac and certain abdominal diseases, but it is mainly employed for determining the condition of the lungs and air passages. Animals can not give the various phases of respiration, as can the patients of the human practitioner. The organs themselves are less accessible than in man, owing to the greater bulk of tissue surrounding them and the pectoral position of the fore extremities, all of which render it more difficult in determining pathological conditions. (See Pl. VIII.)

The air going in and out of the lungs makes a certain soft, rustling sound, known as the vesicular murmur, which can be heard distinctly in a healthy state of the animal, especially upon inspiration. Exercise accelerates the rate of respiration and intensifies this sound. The vesicular murmur is heard only where the lung contains air and its function is active. The vesicular murmur is weakened as inflammatory infiltration takes place and when the lungs are compressed by fluids in the thoracic cavity, and disappears when the lung becomes solidified in pneumonia or the chest cavity filled with fluid as in hydrothorax. The bronchial murmur is a harsh, blowing sound, heard in normal conditions by applying the ear over the lower part of the trachea, and may be heard to a limited extent in the anterior portions of the lungs after severe exercise. The bronchial murmur when heard over other portions of the lungs generally signifies that the lung tissue has become more or less solidified or that fluid has collected in the chest cavity.

Other sounds, known as mucous r‚les, are heard in the lungs in pneumonia after the solidified parts begin to break down at the end of the disease and in bronchitis where there is an excess of secretion, as well as in other conditions. Mucous r‚les are of a gargling or bubbling nature. They are caused by air rushing through tubes containing secretions or pus. They are said to be large or small as they are distinct or indistinct, depending upon the quantity of fluid that is present and the size of the tubes in which the sound is produced. According to their character they are divided into dry and moist. The friction sound is produced by the rubbing together of roughened surfaces and is characteristic of pleurisy.

_Percussion._--Percussion is that mode of examination by which we elicit sounds by striking or tapping over the part. It may be direct or indirect. If the middle finger of the left hand is placed firmly on the chest and smartly tapped or struck with the ends of the first three fingers of the right hand, the sound will be noticed to be more resonant and clear than when the same procedure is practiced on a solid part of the body. This is because the lungs are not solid, but are always, in health, well expanded with air. In certain pulmonary diseases, however, as in pneumonia, they fill up and become solid, when percussion produces a dull sound, like that on any other solid part of the animal. When fluid has collected in the lower part of the chest cavity the sound will also be dull on percussion. Where there is an excess of air in the chest cavity, as in emphysema or in pneumothorax, the percussion sound becomes abnormally loud and clear. By practice on healthy animals the character and boundaries of the sounds can be so well determined that any variation from them will be readily detected, and will sometimes disclose the presence of a diseased condition when nothing else will.

Percussion is sometimes practiced with the aid of a special percussion hammer and an object known as a pleximeter to strike upon. A percussion hammer is made of rubber or has a rubber tip, so that when the pleximeter, which is placed against the side of the animal, is struck the impact will not be accompanied with a noise. A percussion hammer and pleximeter may be purchased from any veterinary instrument maker.

CATARRH (COLD IN THE HEAD).

Nasal catarrh is an inflammation of the mucous membranes of the nostrils and upper air passages. Simple catarrh is not a serious disease in itself, but if neglected is liable to be complicated with laryngitis, bronchitis, pneumonia, plurisy, or other serious and sometimes fatal diseases of the respiratory organs. Catarrh is a common disease among cattle. It is often caused by sudden exposure to wet and cold after they have been accustomed to shelter. It may arise from inhalation of irritating gases. It is also sometimes produced by certain specific atmospheric conditions, and may assume an enzoˆtic form. It is very debilitating, and requires prompt and judicious treatment.

_Symptoms._--Redness of the mucous membranes of the nose and redness and watering of the eyes are symptoms of nasal catarrh. The mucous membrane first becomes dry; afterwards a watery discharge appears, and later, in severe cases, the discharge becomes mucopurulent. In mild cases there is little or no fever, but in severe ones it may run high. The animal becomes dull, languid, and is not inclined to move about, and the appetite may become impaired; there is also variable temperature of the horns and ears. If in a cow giving milk the secretion diminishes, the mucus from the eyes and nose becomes thicker and yellower. Afterwards, as the symptoms increase in severity, the discharge becomes mucopurulent.

_Treatment._--The animal should be housed in a well-ventilated place, with good hygienic surroundings. In cold and damp weather it should be kept warm with blanketing, and, in severe cases, hot, medicated inhalations given. If the fever is high, it may be reduced by giving nitrate of potassium, from 1 to 2 ounces, in the drinking water, three times daily. Diffusible stimulants are beneficial in most cases. Too much importance can not be attached to good nursing. There is no necessity to resort to the old system of bleeding, purging, or the use of powerful sedatives.

EPISTAXIS (BLEEDING FROM THE NOSE).

Bleeding from the nostrils is rather rare in cattle. It may arise from any one of a variety of causes, but usually results from disease or injury to the mucous membranes or to violent exertions in coughing and sneezing. It is seldom serious. It generally occurs in drops from one nostril only, accompanied with sneezing, and without frothing. Bleeding from the lungs comes from both nostrils, is bright red, frothy, and accompanied with a cough.

_Treatment._--In many cases the bleeding will cease spontaneously and all that is necessary is to keep the animal quiet and bathe the head and nostrils with cold water. The cause of the bleeding should be learned and governed accordingly in the treatment. In severe and exceptional cases, when the hemorrhage is persistent and long continued, the animal's head should be tied to a high rack or beam and cold water or ice applied, or recourse to styptic injections taken. If the hemorrhage is profuse and persistent, either a drench composed of 1-1/2 drams of acetate of lead dissolved in a pint of water or 1-1/2 drams of gallic acid dissolved in a pint of water should be given.

LARYNGITIS (SORE THROAT).

An inflammation of the mucous membrane lining the larynx is known as laryngitis. It may be either a primary or a secondary disease, complicated or uncomplicated. In the majority of cases it is attributable to some form of exposure, a sudden change from warm to cold surroundings, or exposure to cold storms. It may also result from inhaling irritating gases or from external violence. In an acute attack of laryngitis there is an elevation of temperature, pain on pressure over the region of the larynx, violent paroxysms of coughing, difficult and noisy respiration. The nostrils are dilated, the nose extended, and the animal has a frightened expression. There is marked difficulty in swallowing.

_Treatment._--Treatment consists of fomentations and hot applications over the throat. Stimulating liniments, mustard mixed with cold water and well rubbed in with a stiff brush, or other forms of counterirritation may be applied in severe cases. Hot inhalations should be frequently resorted to, and often afford much relief to the suffering animal. In this disease medicines should be given so far as possible in the form of electuaries (soft solid) on account of the difficulty of deglutition. Large drafts of medicines have a tendency to produce violent spells of coughing, and in this way retard recovery. The subjoined formula for an electuary will be found to answer the purpose in ordinary cases: Chlorate of potassium, pulverized, 8 ounces; fluid extract of belladonna, 2 ounces; powdered opium, 1 ounce; powdered licorice root, 8 ounces; sirup, sufficient quantity; mix. Place a small tablespoonful of the mixture frequently on the tongue or back teeth. Or the following may be used instead: Aloes, powdered opium, and gum camphor in equal parts; mix. Rub an ounce on the molar teeth every four or five hours. The bowels should be kept open and the diet should be such as the patient can easily swallow. Warm, sloppy mashes, boiled oatmeal gruel, linseed tea, and the like are the most suitable substances. If suffocation be threatened during the course of the disease, tracheotomy should be performed without delay. The details of the operation are fully described under the head of "Surgical operations." (See p. 289.)

When the disease assumes a chronic form, strong counterirritation is indicated. A cantharides blister may be applied, or the following ointment used: Biniodid of mercury 1 part, lard 6 parts; mix. In some cases it will be found necessary to repeat the application.

BRONCHITIS.

Bronchitis is an inflammation of the mucous membrane of the bronchial tubes. When a primary disease, it is generally the result of what is commonly known as "catching cold." It may be secondary to or complicated with many of the diseases of the respiratory system. It may also be caused by breathing irritating gases, or by the introduction of foreign bodies into the bronchial tubes, which sometimes results from injudicious and careless drenching when the larynx is temporarily relaxed. It may be acute or chronic, and is divided, according to the seat of the inflammation, into bronchitis proper when the large tubes are affected, or capillary bronchitis when the trouble is in the smaller ones.

_Symptoms._--Loss of appetite, elevation of temperature, generally 104∞ or 105∞ F. The inspiration is incomplete, short, and painful, and the expiration is prolonged. The pulse is increased in frequency and is hard. A characteristic, painful cough is present, but it is paroxysmal and incomplete. Auscultation and percussion greatly aid us in a diagnosis. A normal sound is given on percussion. On auscultation, in the early stages, rhonchus r‚les are detected if the larger tubes are affected, and sibilant r‚les if the smaller ones are affected. Later mucous r‚les are noted, and sometimes all sounds in certain parts are absent, owing to the plugging up of the tubes. This plugging, if extensive enough, is sometimes the cause of death, or death may result from extension of the disease to the lungs or pleura.

_Treatment._--The animal should be placed in a light, well-ventilated box, and the bowels kept in a soft condition by enemas, etc. Violent purgatives should not be used. The body should be kept warm by blanketing. In the early stages a draft composed as follows should be given three times daily: Extract of belladonna, 2 drams; solution of acetate of ammonium, 4 fluid ounces; water, one-half pint. In the later stage of the disease the following formula may be substituted and given twice daily: Carbonate of ammonium, 3 drams; liquor hydrochlorate of strychnin, 2 fluid drams; spirits of nitrous ether, 1 fluid ounce; water, one-half pint.

In some cases the following is preferable to either of the above, and may be given in a pint of linseed tea every four hours: Spirits of nitrous ether, 1-1/2 ounces; aromatic spirits of ammonia, 2 ounces; powdered camphor, 2 drams. The feed should be light and nutritious.

Bronchitis is liable to become chronic if not properly treated in the earliest stage. In this case remedial treatment is of little value.

PLEURISY.

Pleurisy is an inflammation of the serous membrane lining the chest cavity and enveloping the lungs. It is somewhat rare as an independent disease, but it often complicates pneumonia; indeed, it is often caused by the same germ that causes pneumonia--pneumococcus. It may arise from exposure to cold or wet or from external violence, and is usually present in some degree in cases in which the ribs have been fractured with or without a penetrated wound.

_Symptoms._--In the first stage there is great pain aggravated by movement, and the animal is usually stiff as though foundered, the pulse is quick and hard, the breathing abdominal, the chest being fixed so far as possible, the inspiration short and jerky, the expiration longer. The pain is caused by the friction of the dry, inflamed pleural surfaces of the lung and chest on each other. At this stage the ear detects a dry friction murmur, resembling somewhat the sound made by rubbing two pieces of sole leather together. Pressure between the ribs gives pain and usually causes the animal to flinch and grunt. The muzzle is hot and dry, the mouth slimy, and the secretions scanty. After a day or two the severity of the symptoms is much lessened, the temperature, which during the first days may have been as high as 106∞ F., falls to 103∞ or 104∞, the pain decreases, the stiffness disappears, and the patient eats a little. The pulse softens, but remains quicker than normal. Now, day by day the patient loses a little strength, the friction sound disappears as the exudation moistens the pleural surfaces; percussion now shows a horizontal line of dullness, which day by day rises higher in the chest, the respiration grows more frequent and labored, the countenance is anxious and haggard, the eyes sink somewhat in their sockets, and in unfavorable cases death occurs during the second or third week, from either asphyxia or heart failure.

In pleurisy, as in pneumonia, the elbows are usually turned outward. Care must be taken to differentiate pleurisy from traumatic pericarditis (which see). In the latter condition the area of dullness of the heart is much increased, and usually a splashing sound is heard at each beat of the heart. Another diagnostic symptom of value is that in traumatic pericarditis respiration is painful, not difficult, and the respiratory rate is very much increased on movement. In both conditions a considerable swelling of the dewlap may be noticed in the later stages.

_Treatment._--Give the same general care as recommended in bronchitis or pneumonia. In the early stages give a febrifuge to reduce the fever, as directed for pneumonia. For relief of the cough give electuary formula, which will be found in the treatment of laryngitis. The bowels must be kept relaxed and the kidneys secreting freely. In the stage of effusion the following should be given three times daily: Digitalis tincture, 1 ounce; iodid of potassium, 30 to 60 grains; mix. Apply strong counterirritant to chest and put seton in dewlap. (See "Setoning," p. 293.) If collapse of the lung is threatened, a surgical operation, termed paracentesis thoracis, is sometimes performed; this consists in puncturing the chest cavity and drawing off a part of the fluid. The instruments used are a small trocar and cannula, which are introduced between the eighth and ninth ribs. The skin should be drawn forward so that the external wound may not correspond to the puncture of the chest, to prevent the entrance of air. Only a portion of the fluid should be removed. The animal gets immediate relief, but it is generally only temporary, as the fluid has a tendency to accumulate again.

PNEUMONIA.

Pneumonia is an inflammation of the lung substance, and is divided into three forms, viz, croupous, catarrhal, and interstitial. These various forms, however, can be differentiated only by the expert, and it is therefore deemed necessary for the purpose of the present work to treat the subject under the general head of pneumonia.

The causes of pneumonia in general are the same as those of the various other inflammatory diseases of the respiratory tract. The germ is known as a pneumococcus. The disease mostly follows congestion of the lungs, but may in rare cases have a parasitic origin.

_Symptoms._--In the first stage, that of congestion, the disease is usually ushered in by a chill, although this may not always be observed by the attendant. This is followed by an elevation of temperature, usually 105∞ to 106∞ F., or it may be even higher. The respirations are quick and shallow; the nostrils are dilated; the pulse is full and hard. Cough may or may not appear in this stage. The nose is hot and dry; the tongue sometimes protrudes and is slimy; the coat is staring, and the skin dry and harsh. The urine is usually diminished in quantity, high colored, and the bowels constipated. The animal stands with the forelegs wide apart to facilitate respiration. On auscultation crepitation will be observed over the portion of the lung affected. The sounds elicited on percussion are practically normal in this stage.

In the second stage the temperature generally drops one or two degrees, and respiration is performed with much difficulty. The cough is frequent and painful. The animal still stands with the forelegs wide apart and the elbows turned outward. If it assumes the recumbent position it rests on the sternum. All secretions are more or less suspended, particularly the milk in cows. The animal has a haggard appearance, and the pulse becomes small and wiry at this period. The extremities are hot and cold alternately; the crepitation which was present in the first stage is now absent, and no sound on auscultation is heard, unless it is a slight wheezing or whistling noise. On percussion dullness over the diseased lung is manifested, indicating consolidation. The lung has now assumed a characteristic liverlike appearance.

In the third stage, if the disease is to terminate favorably, the cough becomes loose, the animal improves, the appetite returns, and the symptoms above detailed rapidly subside; if, on the other hand, resolution is not progressing, the lung substance degenerates, becomes clogged up, and ceases to function. In fatal cases the breath has a peculiar, fetid, cadaverous odor, and is taken in short gasps; the horns, ears, and extremities become cold and clammy, and the pulse is imperceptible. On auscultation, when suppuration is taking place and the lung structure is breaking down, a bubbling or gurgling crepitation, caused by the passage of air through pus, is heard.

_Treatment._--Good hygienic surroundings and good nursing are essential in connection with the medical treatment. The probability of recovery depends largely on the extent of the lung tissue involved, as well as on the intensity of the inflammatory process. In the early stage, when the fever is high, febrifuges should be given. If the pulse be strong and full, aconite (Fleming's tincture, 1 to 2 drams, every four or five hours) may be given for a short time, but should be discontinued as soon as the fever begins to abate. Aconite is a valuable drug in the hands of the intelligent practitioner, but my experience leads me to believe that not infrequently animals are lost by its injudicious use, for in many febrile conditions it is positively contraindicated, owing to its action upon the heart. In a plethoric animal, with a strong, bounding pulse, bleeding may be resorted to instead of administering aconite. If the bowels are constipated, calomel, 1 to 3 drams, which acts as a cathartic and a febrifuge, is advisable. In the second stage diffusible stimulants are required, viz: Spirits of nitrous ether, 2 ounces; aromatic spirits of ammonia, 1 ounce; mix, and give in gruel three times daily. In some cases carbonate of ammonia, 2 to 5 drams, has been found beneficial. Most practitioners apply counterirritants, such as mustard plasters, turpentine, and ammonia liniment, or cantharides.

EMPHYSEMA (HEAVES).

Emphysema is a rupture of the minute air vesicles of the lung substance, and may be either interlobular or vesicular. There is an extreme interference with respiration, inspiration being short and expiration prolonged. It is a nonfebrile condition, in which the appetite is not decreased and the milk secretion is kept up. It may be caused by an attack of asthma or may result from chronic bronchitis. The disease can be diagnosed by the marked interference with respiration. The animal, as a rule, is emaciated, has a staring coat, and is hidebound. If percussion is resorted to, the animal's chest will give a tympanic, drumlike sound. The normal resonant sound is exaggerated.

_Treatment._--The disease is incurable, and only a palliative form of treatment can be carried out. The destruction of the animal is often advisable, from a humane as well as from a financial point of view.

PULMONARY CONGESTION.

Cattle that are overdriven or overworked are liable to pulmonary congestion in an acute form, and sometimes to pulmonary apoplexy. In such cases they should be allowed to rest, and if the weather is hot, they should be put in a shady place. Give stimulants internally, unload the venous side of the heart by bleeding, and apply stimulating applications to the legs, and bandage.

HEMOPTYSIS.

Hemoptysis is a term used to signify bleeding from the lungs. The trouble may result from a previous congestion of the lungs or from a breaking down of the lung substance, or from specific disorders.

Bleeding from the lungs comes from both nostrils and from the mouth. The blood is bright red, frothy, and accompanied with a cough, the flow being somewhat profuse and intermingled with mucus. It may cease of its own accord. Internally hemostatics are indicated, and locally over the sides cold applications have a tendency to check the hemorrhage. A drench of 1-1/2 drams of gallic acid dissolved in a pint of water should be given.

ABSCESS OF THE LUNG.

Abscesses of the lung sometimes form during the course of or subsequent to tuberculosis or other diseases. An animal affected with abscess of the lung usually has a protracted, feeble cough and a general appearance of emaciation and anemia. The pulse is feeble and the breath foul. An offensive discharge from the lungs frequently occurs. Percussion and auscultation aid in making a diagnosis in this condition. The appetite is poor. Such animals go from bad to worse, and their prompt destruction would, as a rule, be to the interest of the owner.

HYDROTHORAX.

Hydrothorax, or dropsy of the chest, is not a disease in itself, but is simply a condition in which an effusion takes place in the chest cavity, and is the result or effect of some disease, mostly pleurisy. It can be easily diagnosed by physical signs. A loss of the respiratory murmur will be noticed on auscultation, and on percussion dullness or flatness on a line as high as the effusion has taken place. When a large amount of effusion is present, tapping with the trocar and cannula is generally resorted to. The proper method of performing this operation will be found under the head of "Pleurisy."

PNEUMOTHORAX.

An accumulation of gas in the pleural sac is known as pneumothorax. The presence of air may result from either an injury of the lung or a wound communicating from the exterior. The indications for treatment are to remove any foreign body that may have penetrated, to exclude the further entrance of the air into the cavity by the closure of the external opening, and to employ antiseptics and adhesive dressings. The air already in the cavity will in most cases be absorbed.

VERMINOUS BRONCHITIS.

This is a disease that sometimes attacks young cattle when pastured in low-lying meadows near rivers subject to flood. It is caused by a small worm, _Strongylus micrurus_, which lodges in large numbers in the trachea and bronchial tubes, giving rise to considerable irritation of the air passages and inflammation. Sometimes the strongyles lodge in large numbers in the windpipe, forming themselves into a ball, and thus choke the animal to death.

_Symptoms._--It is liable to attack a number of animals at once, and the weakest are the first to give way. The animal has a remarkably forcible cough, distressing, and of a special hacking and paroxysmal character. A stringy mucus is sometimes expelled during the spells of coughing. This mucus contains the _Strongylus micrurus_, which can be detected, or their ova observed, under a low power of the microscope. The attack has a subacute character and is very exhausting. The parasites, by becoming entwined in balls, seriously impede respiration, which is always remarkably labored in this disease.

_Treatment._--The affected calves should be placed in a dry stable, protected from dampness, and subjected to fumigations of sulphurous anhydrid or chlorin gas. The liberation of chlorin gas is brought about by the action of sulphuric acid, either on a mixture of chlorid of sodium and black oxid of manganese or on bleaching powder. Sulphurous anhydrid may be procured by burning sulphur. Some practitioners prescribe small doses of spirits of turpentine in linseed oil. The system requires good support, and the diet should therefore be liberal and nutritious. Equal parts of sulphate of iron, gentian, and ginger make an excellent tonic.

_Prevention._--Avoid pastures notorious for generating verminous bronchitis.

PLEURODYNIA.

Pleurodynia is a term applied to rheumatism of the intercostal muscles, the apparent symptoms being very similar to those of pleurisy. The animal is stiff, is not inclined to turn around, and the ribs are kept in a fixed state as much as possible. Pleurodynia may be distinguished from pleurisy by the coexistence of rheumatism in other parts and by the comparative absence of fever, cough, the friction sound, and the effusion into the chest. The treatment for this affection is the same as that for rheumatism affecting other parts.

DISEASES OF THE NERVOUS SYSTEM.

By W. H. HARBAUGH, V. S.

[Revised by John E. Mohler, V. M. D.]

THE NERVOUS SYSTEM.

The nervous system is the distinguishing feature of animal life. Without it there can be no intelligence, no instinct, no sensibility, no perception; in fact, existence would be nothing more than vegetable life.

The senses--touch, taste, sight, hearing, smell--all depend on the nervous system. Motion depends on it. A muscle can not contract without receiving the stimulus from the nervous system. For example, if a nerve passing from a nerve center to a muscle is severed, the particular muscle that is supplied by the cut nerve is paralyzed.

The nervous system is often studied in two divisions--the cerebrospinal division and the sympathetic division.

The cerebrospinal division consists of the brain and spinal cord, nerves, and ganglia. The nerves of this division convey the impulses of motion and sensation and supply all parts which are under the control of the will. For example, the voluntary muscular tissue includes all the muscles which act as the will directs. Another example: If anything comes in contact with any part of the skin, the impression is immediately perceived. All the special senses belong to this division.

The sympathetic division consists of nerves and ganglia. The muscular tissue, which acts independently of the will--as, for example, the stomach, intestines, womb, blood vessels, ducts, etc.--is called involuntary muscular tissue, and receives nervous stimulus from the sympathetic division.

The brain, spinal cord, and the ganglia are the central organs of the nervous system. The nerves conduct the nervous influence. The nerves terminate differently according to their function. The terminations are called end organs. The terminal end organs in the skin and other parts endowed with sensation receive the impressions, which are conveyed to the brain, where they are appreciated. They are so sensitive that the most gentle zephyr is perceived. They are so abundant that the point of the finest needle can not pierce the skin without coming in contact with them, and the sensation of pain is instantly conveyed to the brain. The terminal end organs of the nerves that supply the muscles are different, as they give the impulse which is conveyed by the motor nerves to the elements which constitute the muscle, and this impulse is the excitation which causes the muscle to contract. The terminal end organs of the special senses of taste, smell, etc., receive their special impressions, and their respective nerves carry the impressions to the brain.

There are two divisions of nerves, the afferent and efferent.

The afferent nerves are those which convey the impression to the nerve centers. All the sensory nerves belong to this division.

The efferent nerves are those which convey the nervous impulse outward from the nerve centers, and they are further classified according to the function of their respective centers. For example: Motor fibers carry the impulse from the nerve center to a muscle to cause contraction. Vasomotor fibers carry the impulse to the muscular tissue in the blood vessels, which regulates their caliber. The secretory fibers convey the impulse to the cells of the glands and excite the activity of the gland, and its particular product is secreted or evolved, as, for instance, milk in the mammary gland. Inhibitory fibers control or inhibit the action of the organ to which they are distributed, as, for instance, the heart.

Nerve centers may be considered as a collection or group of nerve cells. Both the cerebrospinal and the sympathetic divisions have nerve centers. The centers derive their special names from their functions. The brain is the great center of the nervous system, as it is the center of intelligence and perception. The centers of all the special senses, as well as the centers of various functions, are located in different parts of the brain. Nerve centers also exist in the spinal cord and in connection with the sympathetic system.

A nerve is a cord consisting of a certain number of fibers of nerve tissue, inclosed in a sheath of connective tissue. Nerves divide and subdivide, sending off branches, which ramify in all parts of the body, and, as they near their terminations, they contain but one or two fibers.

The brain and spinal cord are contained within a bony canal, which forms a protective covering for them.

The spinal cord, or spinal marrow, lodged within the spinal canal, or hollow of the backbone, is continuous with the brain anteriorly, and terminates in a point in the sacrum (that part of the spinal column which immediately precedes the tail). The spinal cord gives off branches at each of the spaces between the segments of the backbone. These branches form nerve trunks which carry both sensory and motor impressions and impulses. The spinal cord is a grand nerve trunk to carry messages to or from the brain and to and from the reflex centers contained within itself.

The brain is contained within the cavity of the skull and is continuous with the spinal cord; there is nothing to mark the place where one leaves off and the other begins. The brain is the seat of reason and intelligence. Voluntary effort originates from the brain. Coordination, or harmony of movement, is controlled by the rear portion of the brain, known as the cerebellum.

The meninges are the membranes, three in number, which envelop the brain and spinal cord, and separate them from the bones which form the walls of the cranial cavity and spinal canal.

The sympathetic, also called the ganglionic, division of the nervous system consists of two chains of ganglia, reaching from the head to the tail, situated beneath the spinal column, one on either side. The presence of the ganglia or enlargements on the cords give them their chainlike appearance.

The sympathetic nerves are closely connected with the cerebrospinal nerves, but are not under the control of the will.

INFLAMMATION OF THE BRAIN AND ITS MEMBRANES (STAGGERS).

Inflammation of the brain is technically termed encephalitis and of its membranes cerebral-meningitis, but as both conditions usually occur together, and since it is practically impossible to distinguish one from the other by the symptoms shown by the diseased animal, they may as well be considered together here as varieties of the same disease. Staggers, coma, frenzy, etc., are terms that are sometimes applied to this disease in its different forms or stages.

_Causes._--Severe blows on the head with a hard object, or the head coming violently in contact with the ground or other hard substance in a fall, may be followed by encephalitis. Irritation caused by tumors in the brain may produce inflammation. Feed containing deleterious matters--for example, ergot (see Pl. V) and other fungi which contain a narcotic principle--is the most frequent cause of this affection, and hence it is often called "grass staggers" and "stomach staggers." Highly nitrogenous feeds are blamed for causing this disease. Parasites, mineral and narcotic poisons, hot weather, and severe exertion or excessive excitement may cause this condition. Inflammation of the brain may occur as a complication of some infectious disease or may follow some forms of indigestion. In many localities certain plants have the reputation of causing staggers.