Part 3

1st. The habitual state of health of the subject. The genus, breed, age, environment, habits, (pet dog, watch dog, hound, sheep-dog, ox, bull, cow, milch cow, sheep in the field or housed, pig in pen or at large, diet, regimen, water, race horse, draught horse, work, exposure, etc.) as well as the personal equation of temperament, idiosyncrasy, heredity, etc., must all be carefully considered.

2d. The history of the present illness as to its apparent cause, mode of invasion, duration and progress.

3d. The objective symptoms by which it is manifested. All that can be ascertained in the way of symptomatology, local and general, the probable existence of interdependent disease, and all actual structural lesions and disorders of function should be thoroughly investigated. As supplementary to the more prominent objective symptoms any fever or other constitutional disorder must be sought for; a mental list must be made of the diseases which resemble this one, and these must be excluded one by one by careful attention to the differential symptoms; other diseases which are probably subsidiary to this, should be similarly investigated and excluded; any really diagnostic sign of the suspected disease must be carefully established and the diagnosis finally placed on a solid foundation. The discovery of a constitutional (febrile) disease to which a distinctive name can be given is by no means the end of the diagnosis; the structural lesions of the disease may be largely localized in an unimportant organ where they may remain circumscribed without compromising life, or they may be seated in a vital organ which will render the disease grave to the last degree or necessarily fatal. For example: Anthrax of a dense, dry part of the skin may be a mild local disease; anthrax of an internal organ is usually fatal. Every local complication therefore, should be as carefully diagnosed as the connected constitutional disorder.

But diagnosis cannot always be certain. In the early stages of certain fevers two forms may be as yet indistinguishable and a day or two may be required to develop differential symptoms. In some occult forms of disease all differential symptoms may fail us. A method of diagnosis which has hitherto been applied only to tuberculosis and glanders is manifestly capable of much wider application, to diseases attended with a febrile reaction. This consists in a hypodermic injection of a minimum dose of the sterilized and filtered products of the culture of the disease germ, which produces no effect on the healthy system but causes febrile reaction or local inflammation, or both, in the diseased. This will be treated more fully under the respective diseases.

In connection with such a method, but above all when no such resort has been had, the obscure case should be seen frequently, the course, duration, and termination of the disease should be noted, also its tendency—sporadic or epizootic, and finally the result of treatment. This last resort may often secure diagnosis and cure at once as when a course of iodine cures an obscure actinomycosis.

SYMPTOMATOLOGY. SEMEIOLOGY.

Definition. Symptom. Sign. Constitutional symptoms—local, objective, subjective, direct—idiopathic, indirect—symptomatic, premonitory. Anamnesis. Position. Movements. Decubitus. Acute. Chronic. Fever. Sthenic. Asthenic. State of limbs, muzzle, nose, snout, palmar-pad, hoof, bill, digits, mouth. Thermometry. Normal temperature, in doors, in field, at work, in hot season, in nervous subject, in thirst, in youth—age, starvation, plethora, cold, sleep, rest, stimulants, suppressed perspiration, eliminants, antipyretics. Fever temperature, morning, evening, transient elevation, persistent rise, sudden fall—collapse, crisis. Fatal elevation. Rise during defervescence. Pulse. Respiration. Skin, staring coat, pallor, coldness, dryness, harshness, mellowness, pliancy, hidebound, yolk, clapped wool, scurfy, lesions, itchiness, tenderness, loss of hair, emphysema, anasarca, sweat, sebum. Expression, life, dullness, paralysis, dropsy, jaundiced, eye, discolorations, photophobia, amaurosis, pinched face. Nasal mucosa, red, violet, etc., nodules, polypi, osseous disease, pentastoma, œstrus, discharge from teeth—sinuses—actinomycosis—tumors. State of the bowels, kidneys, nervous system.

The usual basis of diagnosis must be a clear and intelligent observation of the symptoms of disease. A symptom is an appreciable evidence of disease. A symptom however may indicate illness, without affording the means of diagnosis, while the term sign is often used for a pathognomonic symptom—one by which the disease can be identified. Used in this sense a sign may be said to be a diagnostic symptom.

1. =Constitutional Symptoms= are such as affect the entire system, like a rise of body temperature, or a shivering fit.

2. =Local Symptoms= are confined to a definite area as redness, tenderness, swelling, ulceration.

3. =Objective Symptoms= include all that can be recognized by the senses of the observer. These alone are available in dealing with the lower animals.

4. =Subjective Symptoms= can only be felt by the patient himself, as pain, giddiness, cold, heat, blindness, numbness. Such symptoms are therefore only obtainable from the human patient who can tell how he feels. In the lower animals they can only be matter of inference, thus pain may be inferred from lameness or wincing on pressure, and giddiness from unsteady gait. The fact that the veterinarian is restricted to objective symptoms renders his task a specially difficult one, yet this has its compensation, as this very restriction tends to train the observant practitioner to greater skill.

5. =Direct Symptoms= (=idiopathic=) are those which are connected with the seat of disease, as the redness, exudation, and swelling of inflammation.

6. =Indirect= (=sympathetic=, =dependent=) =Symptoms= are observable at a distance from the actual disease:—as when headache attends on dyspepsia, or lameness in the right shoulder upon disease of the liver.

7. =Premonitory= or =precursory symptoms= precede the diagnostic symptoms of some diseases, thus dullness and languor often heralds an approaching fever, and the strangles of young horses is often preceded by a general unthrifty appearance, poor appetite and indisposition to exertion.

In observing symptoms as in other things, some have far greater natural ability than others, but in all a careful training will do much to develop and improve the power and habit. A most important thing in such habits is the strict maintenance of a system, not to be followed as a cast iron rule but to be constantly kept in mind and strictly carried out except when sound judgement and experience show it to be unnecessary.

=Anamnesis.= As a rule the first thing to be learned about a patient is his history, and personal and hereditary characteristics. What are his general health, temperament, previous attacks, hereditary predisposition, environment? Is the site of the building, its condition as regards soil, springs, drainage, structure, ventilation, light, cleanliness such as would favor any particular disorder or class of disorder? Is the patient in high, low, or moderate condition, robust or debilitated, alert and lively or dull and stupid? Have other animals suffered recently, or at a corresponding season, or under similar conditions in apparently the same manner? How long has the patient suffered, were there any premonitory indications of illness, what were the first symptoms, and what symptoms have followed up to the present? Has there been any change of food, water or management that might throw light on the cause? Has there been any change of weather or unwonted exposure to cold, storm, overwork, compulsory abstinence or enforced retention of some secretion? If a female is she pregnant?

Having exhausted this method, using such lines of inquiry as promise good results in the particular case, the veterinarian is prepared to bring his own powers of observation to bear more directly.

=Position= and =movements= will often furnish valuable data. The horse which lies on his ribs, stands obstinately in chest diseases, or whenever there is much interference with breathing. The ruminants and carnivora on the other hand which lie on their smooth or padded sternum, can breath with comfort in this position and only stand up persistently in the worst cases. The habit of standing day and night is also characteristic of anchylosed back or loins in the solipede. Roached back may be natural, or the result of overwork and slight sprains or injuries of the loins, of anchylosis, of intestinal or renal inflammation, or of certain injuries to the limbs. The extension of the head on the neck may suggest sore throat, chest disease, tumors around the throat, abscess (fistula) of the pole, sprain or spasm of the extensors of the neck, disease of the axoido-atloid joint, tetanus, or cervical rheumatism. Dropping of head and neck might suggest paresis, mechanical injury to the levator muscles or cervical ligament, extreme debility, or prostration from a profoundly depressing fever or poisoning. Inability or indisposition to back, might indicate sprain or fracture of the back, anchylosis, laceration of the sublumbar muscles, paresis, cerebral or spinal inflammation, softening or other lesion, tetanus, laminitis, dislocated patella and certain other affections. Swaying or unsteadiness in walking or turning would similarly suggest sprain or fracture of the back, paresis and other nervous and locomotor injuries. The solipede with peritonitis arches the back and draws the hind feet forward under the belly, with impacted colon or obstruction to urination he will often stretch with fore limbs advanced and hind limbs retracted. The mode of decubitus may be significant. With peritonitis, enteritis, metritis or acute nephritis or hepatitis the solipede lies down slowly and with caution: with spasmodic colic he throws himself down as if reckless of possible injury. Lying well up on the costal cartilages and side of the breast bone suggests a slight affection of the air passages; lying on the side, disease of other parts. Rolling on the back may indicate simple intestinal spasm, but also blocking by intussusception, impaction, volvulus or otherwise. Sitting on the haunches may suggest a similar trouble or it may imply ruptured stomach or diaphragm. The dog may sit on his haunches in health, or with dyspnœa in acute affections of the respiratory organs, asthma and heart affections. Decubitus on the belly with hind legs extended backward, may imply paraplegia, or acute inflammation of the abdominal organs. Lying with the nose in the flank or turning the head toward the flank, though a normal position of rest, often indicates abdominal suffering. Turning of the head to one side may, however, suggest injury, spasm or rheumatism of the cervical muscles, or disease on the corresponding side of the brain. Animals, at liberty, lie more frequently on the side on which the heaviest internal organs are lodged, thus ruminants, pigs, and dogs rest on the right (the side of the liver) though in cattle with a heavily loaded rumen the condition may be reversed. Decubitus on the abdomen, with the limbs extended and abducted implies profound nervous disorder or shock.

Habitual decubitus often indicates severe suffering in legs or feet. Resting one limb more than another implies injury to that limb. Standing with the pastern of one limb more upright than the others has the same meaning. Extension of one fore foot in advance of its fellow with flexion of the pastern and fetlock denotes suffering in the posterior part of the foot or in the flexors. Flexion of carpus and fetlock without advance of the foot probably bespeaks injury to shoulder or elbow. Inability to bear weight on the fore limb, without knuckling at the knee, should call for examination of the olecranon and joints especially the elbow. Inability to extend the carpus should lead to investigation of the flexor muscles and tendons, the joints and the heel. Movement of the hind limb without flexure of the tarsus would suggest injury to that joint, the stifle or the flexor metatarsi tendon. Inability to extend stifle and hock, should demand examination of the tendo-Achillus and olecranon, of the triceps extensor cruris and of its nerves.

Atrophy of a muscle or group would require scrutiny of its tendons and its nerve and blood supply.

More precise indications of injury of the locomotor system must be found under surgery.

After posture, the general or constitutional disorder may claim attention. Is the illness acute or chronic? Is fever present? Has the animal had a rigor? Does the coat stare in patches (along the spine) or generally? Is there perspiration? Is there full, clear, somewhat congested eye (=sthenic=) or drooping lids over a dull brownish sclerotic (=asthenic=). Are the lower parts of the limbs and other extremities cold, and the roots of the horns or ears hot? Is there significant heat and dryness of the muzzle (ox), nose (dog), snout (pig), palmar-pad (carnivora), hoof (solidungala, bisulcates), bill and digits (birds)? Has the mouth the hot burning feeling of fever? Finally is the temperature as indicated by the thermometer abnormally high? To estimate this with any degree of certainty one must be well acquainted with the normal temperature.

=Normal temperature.= As taken indoors under ordinary conditions, the normal temperature taken in the rectum may be: fowl, 107°–110°F.; swine, 103°–106°F.; goat and sheep, 103°–104°F.; ox, 100°–102°F.; dog, 99°–100°F.; horse, 99°–99.6°F. Ranging in the fields, at work, or on forcing or stimulating feeding, it may be 1° higher than when at rest indoors. A whole herd may be raised 2° by a three miles drive in warm weather. In our summer heats a rise of 1° is common. In nervous animals any change in management may raise the temperature, for example, 1° to 2° after failure to water at the usual time, or from retaining the milk in the udder when the milker had been changed. Young animals are normally .5° to 1° warmer than old ones though more sensitive to the action of cold. Half starved animals, when put on abundant and nutritious food may have a rise of 1° or more. Females in heat, in advanced pregnancy and at the time of parturition are usually 1° to 3° above the natural temperature. Among the agencies lowering temperature are: cold, (1° to 2°); sleep, (1° to 2°); rest; starvation; alcoholic and other circulatory stimulants which fill the cutaneous capillaries and thereby cool the whole mass of blood; suppression of insensible perspiration (retention of waste matters) as by varnishing the skin which lowers the temperature to 25°; purgatives and diuretics (1°); certain drugs like antipyrin, acetanilid, etc., which act on the heat producing centres and retard metabolic changes.

=Temperature in disease.= Comparative temperatures should be taken at the same hours on successive days, bearing in mind that the morning temperature is usually slightly lower and the evening one slightly higher. Where possible both morning and evening temperature should be taken. With elevated temperature, repeat sooner to see that it is not transient. A transient rise of 1° to 2° is unimportant. A permanent rise of 2° or 3° indicates fever. A sudden additional rise of several degrees in the progress of fever is grave. A persistence of the high evening temperature to morning shows aggravation. A persistence of the low morning temperature to the evening bespeaks improvement. A sudden extreme fall to much below the normal (4° or 5°) indicates collapse. This is usually attended with other symptoms of extreme prostration and sinking. A sudden considerable fall to near the normal, without untoward attendant symptoms, may indicate a crisis and a more or less speedy improvement may be hoped for. This sudden fall often attends the period of eruption of certain exanthemata, as cowpox, horsepox, sheeppox, aphthous epizootic, etc. A sudden extensive fall of temperature may result from some transient accidental cause, as a prolonged deep sleep, a hemorrhage, the relief of constipation, or of enuresis. A sudden rise may supervene on such suppressed function or other cause of nervous irritation or on toxin poisoning, but it does not persist more than twelve or twenty-four hours after the cessation of the morbific cause.

A rise of 10° or 12° above the normal standard is usually promptly fatal.

A continued high temperature indicates persistent disease, and a considerable rise during defervescence implies a relapse and in the absence of any error in diet or nursing is grave.

=Pulse.= Before the introduction of the clinical thermometer, the indications furnished by the pulse were held to be of the highest value. Though largely superseded by the usually more reliable thermometer, yet they should not be discarded, but employed as symptoms corroborative of the thermometric indications. In many cases the pulse will furnish criteria, when in the absence of fever, the heat of the body will tell of nothing amiss. This is especially true of diseases of the heart, the large blood vessels, and of the nervous system, and in cases of poisoning. For special indications furnished by the pulse, see diseases of the heart.