3 General Examination of the Patient

Disease processes in the body can be divided into two main groups: those associated with inflammation and those of a non-inflammatory nature (injuries, neoplasms, obstructions, meta­bolic disorders, nutritional deficiencies, etc.). Inflammatory changes generally give rise to certain characteristic signs—pain, redness (only obvious when it occurs in non-pigmented skin areas), swelling, increased temperature of dis­eased organs, increased body temperature (fever) and impairment of function. In non-inflamma­tory processes, swelling and disturbance of function of the diseased organs may likewise occur but, in general erythema, heat and pain are absent. The presence of the last three signs always suggests that the disease has inflammatory characteristics. In acute processes (those run­ning a rapid course) these signs are well marked, but in chronic processes (those running a slow course) they are much less obvious. Not every structural defect or functional change in the body will necessarily result in an obvious dis­turbance of health. The presence of small tu­mours in the liver, lung, mammary gland or other organ, although detectable by various means, may produce no overt clinical signs of disease, and the heart may function adequately in spite of minor valvular or functional defects.

Routine for Clinical Examination

Because the patient cannot communicate any verbal information as to the probable situation of the disease, the examination of the ailing animal must always be carried out in such a way that no organ or tissue is omitted from the inves­tigation. In order that nothing is overlooked, it is advisable to carry out the examination according to a routine pattern. The order in which the various parts of the clinical examina­tion are performed is a matter for personal choice, although it is recommended that certain procedures, such as ascertaining body tempera­ture, taking the pulse and determining the respira­tory frequency, should be performed before others which involve the risk of unduly disturb­ing the animal. The systematic scheme followed here can be adopted or modified to meet personal requirements; the essential point is not to omit anything and this is best accomplished by becom­ing so accustomed to one particular sequence that its use becomes a matter of habit. The best way to reduce errors in diagnosis is always to make a thorough and complete clinical examina­tion. The majority of incorrect diagnoses result from the omission of one or more parts of the examination.

In all cases the history of the patient is thoroughly elucidated in the manner previously described, and a general inspection of the animal and its environment is carried out prior to the general and physical parts of the clinical exa­mination. The general inspection of the animal is important in that it enables the behaviour of the animal to be assessed before it has been unduly disturbed by the near approach of the clinician or the need to apply any form of physi­cal restraint. The value of the general inspection is reduced in animals brought into a strange environment, such as the veterinarian's waiting room or surgery. The following points are important in determining the identity and health status of an animal, and should always be reviewed within the preceding context.

Suggested routine for mammals. The procedure involved in making a clinical examination can usefully be classified into two phases: (a) the general examination which includes the general inspection and (b) the regional and/or systematic examination.

The general clinical examination involves de­tailed consideration of the following: (1) dis­tinguishing marks; (2) physical condition; (3) general appearance and demeanour; (4) posture;

(5) gait; (6) abnormal behaviour; (7) body tem­perature; (8) pulse; and (9) respiration.

The regional or systematic clinical examina­tion involves the application of the various clinical methods (sensory and physical) to the various regions or systems of the body as follows: (1) coat and skin; (2) head and neck; (3) thorax; (4) abdomen; (5) urinary system; (6) reproductive system; (7) blood and blood-forming organs; (8) nervous system; and (9) musculoskeletal system.

The necessity to perform a detailed examina­tion of any particular part of the body may have been indicated by the information obtained during the general clinical examination. If otherwise, all the component regions and sys­tems, as indicated, may have to be thoroughly explored for evidence of disease. The details relating to the regional and systematic examina­tion are set out in Chapters 7 to 15 of this text.

Distinguishing Marks

The distinguishing features of an animal should be carefully noted at the beginning of the examination when the general inspection is made, in order to establish its identity. This is of par­ticular importance if legal evidence regarding the animal is likely to be required. Accurate identification of the patient is also essential for group disease records, in situations where a repeat visit may be made by a different veterina­rian and for accounts purposes. The data re­quired include: name and address of the owner, species, breed (dominant breed characteristics in crossbred animals), sex, age, height or size, colour markings, horned or polled, brands, tattoo marks and permanent blemishes or de­fects (large scars, blindness, overshot jaw, etc.).

In the horse, it is useful to note also the colour of the hoofs, and whether there are any unpig-mented stripes, or defects, such as a false quarter, keratoma or areas of flattening, or even concavity, instead of the normal convexity. The presence of a wall eye (unpigmented iris) or the habit of showing the white (sclera) of the eye should also be noted. In some countries, e.g. the United States of America, racehorses are tat­tooed on the mucous membrane of the upper lip, and the size and shape of the chestnuts are recorded by means of a photograph. The whorls of hair can also be used as a means of identifi­cation ; this consists in measuring the distance of the frontal whorl (situated on the upper part of the face just above the eyes) from the origin of the forelock, and of the tracheal whorl (situa­ted on the ventral aspect of the neck) from the junction of the larynx with the first tracheal cartilage.

In cattle, ear tattoo marks, which are usually employed in conjunction with disease eradication programmes such as tuberculosis, brucellosis, etc., as well as for identification by breed socie­ties, provide a ready means of identification. Certain distinctive breeds, such as the Friesian (Holstein), permit the use of a simple black and white colour sketch for easy and accurate identification.

In the dog, the type of coat (long, curly, smooth- or wire-haired), the form of the ears (pendulous, erect or cropped) and the state of the tail (natural or docked) are noted. In this species (and less commonly in the horse and ox) some or all of the coat may have been dyed. This can often be detected by a close examination of indi­vidual hairs near the roots; plucking out some of the hairs is usually helpful. For very accurate identification in the dog (e.g. racing greyhounds, foxhounds), and also in the ox, a coloured impression can be taken of the skin of the muzzle, on the same principle as that employed in the identification of persons by means of fingerprints. Note may also be made of the colour of the dog's claws. The written descrip­tion of an animal may often be made much clearer by means of a simple sketch or photo­graph.

Observation of the identifying characteristics of the animal is not only necessary for purposes of recognition, but may be of assistance in diagnosis. There are, for example, diseases that occur only in the intact male or female animal (inguinal and scrotal hernia, seen most fre­quently in young hog pigs and colts, or diseases of the reproductive organs). There are also those which occur chiefly in the young animal (joint-ill, white scour, strangles, blackleg, canine dis­temper); those related to size (laryngeal paralysis in big horses); those associated with colour of the coat, which may be a breed characteristic (melanomas in grey horses or photosensitization which, in cattle, occurs most frequently in the Hereford and Ayrshire breeds); those affecting only certain breeds (progressive retinal atrophy in Irish setters and miniature poodles); and many others. Determination of the age of the patient may be pertinent in relation to the economics of continued treatment, more par­ticularly so in chronic affections.

Physical Condition

It is usually easy to assess the bodily condition of the animal by simple inspection. The method is unsatisfactory only in long-haired or long-wooled animals, in which it is necessary to run the hand over certain parts of the body (ribs, spine, shoulder, pelvis, root of tail). Physical condition may be classified as being normal, obese, thin or emaciated. In normal, well-conditioned ani­mals, all parts of the skeleton are covered with flesh, giving the body a rounded appearance (see Figs 121, 122, p. 117). In those in poor (thin) condition, various parts of the skele­ton are prominent (e.g. ribs and pelvis) and the supra-orbital fossae are deepened. The difference between thinness and emaciation is one of degree; in addition, however, the coat is lustre­less, staring and dry, the elasticity of the skin is reduced (hidebound) and the mucous mem­branes are pale and watery. Emaciation (cachexia) is a sign of disease (Fig. 9). Fluctuation in bodily condition can be most accurately determined by weighing the animal at regular intervals. Changes in bodyweight can occur gradually or with great rapidity. Severe wasting is a common accompaniment of old age (Fig. 10), severe intestinal parasitism and extensive or diffuse neoplasia.

Loss of bodily condition can be caused in various ways. It occurs when too little food is provided or eaten, when too much nutrient material is being metabolized or when the inges­ted food is inadequately digested or inefficiently utilized following absorption. The following pos­sibilities should be considered: dietary errors; loss of power to prehend food or unwillingness to do so because of pain; chronic wasting diseases, as for example, Johne's disease, cobalt deficiency, parasitic gastroenteritis, fascioliasis, tuberculosis, pyelonephritis, internal neoplasia, etc.; diseases arising from disturbance of meta­bolism, such as diabetes mellitus; or excessive fluid loss from the body. A tendency towards leanness may be constitutional, hereditary (the influence of high productive capacity, which usually is the cause of leanness in the dairy cow, may originate in this way) or the result of endo­crine disease or enzyme deficiency. An animal may be emaciated in spite of a good, even an excessive, appetite, e.g. in chronic nephritis, cer­tain types of pancreatic disease and cerebral disease.

The opposite of emaciation is the excessive deposition of fat in the body. If this is sufficient to cause systemic disturbances (dyspnoea, etc.), it is described as obesity or adiposity (Fig. 11). In many species, excessive deposition of fat is produced by deliberate overfeeding, as in the case of cattle being fattened prior to slaughter. Even without an excessive intake of food, how­ever, certain diseases, particularly of the endocrine glands (thyroid, pituitary), cause an excess laying down of fat because of reduced basal metabolism. Castration of male and female animals increases deposition of fat. Fat may be laid down over the whole body, or only in certain parts (e.g. in the crest in the stallion, at the base of the tail in the 'fat-tailed sheep).

Gross obesity usually indicates that the cause has been present for a considerable length of time. Extreme emaciation may also be the result of a chronic process but, as in subacute grass sickness in the horse, it may develop within a week.

The assessment of conformation may be made when physical condition is under consideration. The evaluation is based on the symmetry, shape and relative size of the different body regions. Disproportionate enlargement of the abdomen is the more usual abnormality of conformation seen in animals. Changes in conformation occur in dropsy of the foetal membranes, ascites, chronic exudative peritonitis, rickets and nymphomania. Conformation will be given more de­tailed consideration in the description of the body regions.

General Demeanour

Both at the beginning and during the course of the clinical examination the general demea­nour of the animal should be noted, due allow­ance being made for age and temperament. In the case of animals in a herd or flock, separation of an individual may be an indication of disease. When, on being approached, an animal makes a normal response to external stimuli, such as movement and sound, the demeanour is said to be bright. Normal reaction under these circum­stances may consist of elevating the head and ears, turning towards and directing the attention at the source of the stimuli, walking away and evincing signs of attack or flight.

Various abnormalities of behaviour may be exhibited, including dullness or apathy, which state is appreciated by the reactions to normal stimuli being sluggish or retarded, or even some­what suppressed. The so-called 'dummy' state is an advanced degree of failure to respond to external stimuli although the animal remains standing and is capable of movement. It occurs in liver fibrosis and encephalomyelitis in the horse, and in listeriosis and occasional cases of lead poisoning and ketosis in cattle. The most advanced degree of apathy is coma, in which the animal is unconscious and fails to respond to painful stimuli, as in the cow in the advanced stages of parturient hypocalcaemia. Increased responsiveness to external and other stimuli varies in degree from mild to frenzied. When mildly anxious, or apprehensive, the animal ap­pears alert, looks about constantly, but exhibits normal movements. Behaviour of this type is an expression of slight constant pain, or of anxiety, as in serious defects of vision or the early stages of parturient hypocalcaemia. Restlessness is a more severe state in which movement is almost constant, consisting of lying down, rolling, getting up again, looking at the flanks, kicking at the belly and groaning or bellowing. This form of behaviour is usually caused by sharp intermittent or constant pain, as in the colic syndrome in the horse. The more extreme forms of abnormal behaviour include mania and frenzy. In mania the behaviour aberrations appear to be compulsive and include vigorous licking of some specific part of the body surface (ketosis, pseudorabies), pressing forwards with the head (meningitis) or licking or chewing in­animate objects. When frenzied, the animal's actions are uncontrolled as in acute lead poisoning, hypomagnesaemic tetany and rabies. When death is imminent, animals may show anxiety with a fixed, haggard expression.

Posture

When approached in the lying position, most normal animals will get up. Various abnormali­ties of posture may be shown by animals, some of which do not indicate disease, but if they occur in association with other clinical signs then a disease process should be suspected. Changes in posture take the form of curvature of the spine, high or oblique carriage of the head and neck, unusual position of the limbs, etc. Most of these postural aberrations may arise from a variety of abnormalities; their origin can, therefore, be determined only by appropriate further examination of the organs and systems concerned. Diseases of the follow­ing structures have to be considered: bones, joints (Fig. 12), ligaments, tendons (Fig. 13), tendon sheaths, bursae, muscles, nervous system, ears, skin, hoofs and claws. Change of posture which does not indicate disease is seen in de­bilitated or tired horses, when they rest the limbs alternately, placing one foot on its toe, with the heel elevated and the fetlock joint flexed, a little in front of the corresponding one. When affected with laminitis, or during the early stages of osteodystrophia fibrosa, the horse continually shifts its weight from limb to limb. The presence of abdominal pain may be indicated by the animal arching its back (Fig. 14), placing the feet more closely together when standing still, depressing the back and moving the feet more widely apart. The postural be­havioural signs associated with abdominal pain in animals are not very characteristic in most species, except in the horse in which various changes in posture are part of the abnormal behaviour patterns giving rise to the clinical syndrome termed colic.

In acute gastric distension in the horse, pain and pressure on the diaphragm cause the animal to adopt the 'dog sitting' posture in association with periodic rolling and vigorous kicking at its belly. Pain in the chest, or difficulty in breathing, gives rise to obvious abduction of the elbows. As the result of increased muscle tone, animals affected with tetanus show erection and rigidity of the ears, restricted limb movements, immo­bilization of the eyelids and partial elevation and rigidity of the tail. Sheep, during the early stages of pregnancy toxaemia and scrapie, adopt a characteristic posture with the head in an elevated position and the ears pricked (listening attitude). In painful, unilateral conditions of the pharyngeal region, the head and neck are exten­ded (see Fig. 108, p. 103) or held to one side. Abnormal posture may arise from a develop­mental defect (Fig. 15).

The recumbent animal may also manifest postural abnormality. Cattle affected with par­turient hypocalcaemia often lie in sternal re­cumbency with the head deviated towards the flank. Sheep, similarly affected, assume the same posture but the hindlegs are extended posteriorly in a frog-like attitude; in cattle this latter position is indicative of bilateral hip dislocation. In cattle affected by unilateral sciatic nerve paralysis or dislocation of the hip the affected limb sticks out in an awkward position.

Gait

Locomotor disturbances are seen when the animal moves about voluntarily, or is led or driven at various paces past, towards or away from the clinician. Limb movements can be assessed by reference to their rate, range, force and direction. Abnormal movements include lameness, stiffness, shortened stride, stilted gait, exaggerated flexion (Fig. 16), abduction of one or more limbs, stumbling, staggering, swaying of the hindquarters, forced movements, and so on. The locomotor disturbance may be constantly or only intermittently present, and may gradually disappear or become more pronounced with exercise.

As might be expected, locomotion is affected in many developmental diseases of the nervous system, including the following: swayback; enzootic ataxia; cerebellar hypoplasia, an here­ditary disease occurring in calves of the Hereford, shorthorn, Guernsey and Holstein breeds; cere­bellar atrophy of lambs; inherited ataxia of calves and in poisoning with Claviceps paspali, in all of which all qualities of limb movements are abnormal. In louping ill, affected sheep manifest a high-stepping hackney-like gait with occa­sional jumping movements in which all four feet are off the ground simultaneously. Walking in circles is a characteristic feature of gid and listeriosis in sheep (it also occurs periodically in ketosis and pregnancy toxaemia); it is usually associated with rotation or lateral deviation of the head. Changes in gait also occur in diseases primarily affecting muscles (blackleg, muscular dystrophy, azoturia), bones (rickets, osteomalacia, neoplasia), joints (bacterial arthritides, osteoarthritis) and feet (foot-and-mouth disease, 'fouls', footrot). Abnormalities of gait due to muscle dysfunction may be inherited as in in­herited spastic paresis of cattle, a condition affecting calves of the Holstein, Aberdeen Angus, Red Danish and a number of German breeds. The calves are normal at birth, the signs appearing when they are several weeks to six months of age. Due to hypertonicity of the gastrocnemius muscle the hock is straightened and the affected limb is thrust backwards when the calf is walking and then advanced with a swinging motion. Compulsive movement in a forwards direction occurs in the 'dummy' syn­drome characteristic of liver disease and encephalomyelitis in the horse.

It should be remembered, however, that the origin of a locomotor disturbance may lie out­side the nervous or musculoskeletal system, as in laminitis in the horse, which is basically an allergic reaction to certain proteins present in cereal foods, or derived from the placenta, if retained; in cattle the disease occurs occasionally as a sequel to metritis, mastitis, retained pla­centa and mammary oedema. When animals are inspected indoors, the nature of the flooring should be taken into consideration. Very young pigs, for example, may have difficulty in keeping their feet on the smooth bare concrete floor sometimes seen in heated creeps.

Abnormal Behaviour

Departure from normal behaviour on the part of the animal should be considered of clinical significance, and warranting further investiga­tion. In many cases, unusual behaviour arises from a pain stimulus. Abdominal pain is indi­cated by grunting, groaning, grinding the teeth, whining, looking round at the flank, etc. The signs are not very characteristic in most species except in the horse, which has a distinctive way of indicating the presence of abdominal pain. This is spoken of as colicky pain or an attack of colic. From an appreciation of the nature of the abnormal behaviour, certain diagnostic infor­mation can be deduced. In an attack of colic, its severity, duration and the assumption of ab­normal postures are noted. In a mild attack, the horse looks round at the flank (Fig. 17), kicks at the abdomen, swishes the tail and lies down for short periods (mild intestinal spasm, catarrhal enteritis, recent obstruction of the small colon). In an attack of moderate severity, the horse is restless, frequently lies down and occasionally rolls, but usually gets up immediately (obstruc­tion of the large colon, intestinal tympany). In a severe attack, the animal behaves recklessly, throws itself to the ground, rolls frequently, remains lying on its back for variable periods, runs against the wall, walks aimlessly, frequently injures itself and is dangerous to approach (in­testinal volvulus, strangulated hernia, severe spasm of the intestine). The whole attack may be short, lasting for about 15 minutes, or prolonged, lasting for several hours or a day or more. It may be continuous (volvulus, strangulated her­nia, intussusception) or there may be short or long remissions, sometimes for as long as a day (impaction of the large colon). Shortly before death, however, when a state of collapse is present, although pain is very severe, the animal stands quietly and is rigid and unmoving.

In certain types of equine colic, characteristic postures may be assumed, for example standing with both fore- and hindlimbs extended, which is a behavioural sign in severe impaction of the large colon and of the caecum (Fig. 17) and in large tumours in the abdomen (when this is accompanied by protrusion of the penis, it may be an indication of urethral obstruction); the dog may occasionally adopt this posture for brief periods when there is partial obstruction of the colon caused by volvulus or intussuscep­tion. Sitting on the haunches, like a dog, is seen in horses affected with gastric distension, and kneeling, particularly in volvulus.

Care must be exercised, in the horse, to dif­ferentiate between the pain manifestations aris­ing from alimentary disorders (true colic) and those associated with other diseases such as pleurisy, certain genitourinary diseases, etc. (false colic).

Heavily pregnant stalled cattle, particularly after a full meal, may stand with their hindlegs extended backwards into the dung channel, in order to reduce the pressure of the abdominal viscera on the diaphragm. When recumbent, such animals may grunt slightly at each expira­tion for considerable periods. Neither of these manifestations, which are indicative of slight discomfort only, should be mistaken for a sign of abdominal pain.

Involuntary movements are responsible for more or less obvious changes in normal behav­ioural patterns; they include tremor and convul­sions. Tremor is a persistent, repetitive twitching of the skeletal muscles; it may be localized or generalized and is often visible, but is always detectable by palpation. As a rule active move­ment by the affected animal intensifies the tremor. Convulsions may involve the whole or only a part of the body, and consist of violent muscular contractions which usually continue for short periods with intermissions of variable duration, or they may appear to be continuous, as in late stages of many acute encephalitides. Clonic convulsions, in which repeated muscle spasms are interspersed with periods of relaxa­tion, occur much more frequently than tonic convulsions, which occur chiefly in strychnine poisoning and tetanus, and consist of continuous muscle spasm which may be intensified periodi­cally to become clonic.

Bad habits or vices are often expressed in distinctive behaviour. Vices include persistent refractoriness while being led, ridden or worked; jibbing (balking); restiveness during saddling; undue sensitivity of the head, shying at appa­rently imaginary objects; jealousy with food; viciousness; weaving (swaying from one fore­foot to the other); urinary incontinence in the dog. Although such behaviour is usually regar­ded as being habitual, it may sometimes be pathological. Viciousness and balking in the mare may be associated with ovarian cysts; urinary incontinence in the dog with disease of the bladder, kidneys or spinal cord, and in the bitch with hormonal imbalance following ovaro-hysterectomy; resentment of saddling in the horse with disease of the withers or saddle area; shying with defective vision, and so on. Certain vices may have an hereditary basis.

Other forms of abnormal behaviour originate from the acts of eating, defaecation and urina­tion. Such conduct will be considered in detail in the appropriate section of the text. In order to extend the information available in the context of the immediate history, it is pertinent at this juncture, however, to ascertain the state of the appetite for food and water. If the animal has retained its appetite, variation in the quantity of food consumed may have been observed, along with abnormality of prehension, mastication or swallowing; in cattle, the frequency and charac­ter of rumination may be abnormal. The fre­quency of defaecation and the character of the faeces may have been observed to be abnormal; the faeces, if available, should always be examined. Similar consideration should be given to the act of urination. Cattle and sheep affected with foot-and-mouth disease salivate excessively and, as the result of jaw movements during attempts to swallow the saliva, produce a smack­ing noise in the case of cattle, and an abrupt snapping sound in the case of sheep. The act of defaecation may be difficult, and accompanied by straining with groaning (tenesmus) (see Fig. 151, p. 189) in conditions giving rise to constipa­tion, and in paralysis of the rectum or colon, or stenosis of the rectum. In painful abdominal diseases, e.g. peritonitis, acute nephritis, etc., and inflammatory conditions of the anal region, defaecation is difficult and painful. Straining movements may also be caused by abnormalities in the urinary tract, e.g. partial obstruction of the urethra, and in the genital tract, e.g. infectious pustular vulvovaginitis of cattle.