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.