Physical Examination

With the animal properly restrained, the physical examination can now progress to specific palpation, auscultation, and percus­sion. Obtaining a sample of urine for urinalysis is of great value if incorporated into the physical examination; it is easy to perform with the use of dipsticks such as N-Multistix (Bayer AG, Leverkusen, Germany).

■ TABLE 1.1

Normal Values for Temperature in the Ruminant^1-3

breathing until urination is stimulated.

Body temperature is then measured with a rectal thermom­eter. Normal values for each species are given in Table 1.1. There are no absolute values, and the upper and lower limits should be adjusted as needed to account for ambient temperature and housing. For example, if the ambient temperature is greater than 37.5° C (100° F), a body temperature of 39.5° C (103° F) may still be considered normal for the adult bovine, especially if the animal is not allowed access to shade. When body temperatures approach 41° C (106° F), as a result of high ambient temperatures, heat stroke may occur. Keep in mind that the animal tries to maintain its body temperature within these normal limits, and marked deviation from the norm would be indicative of a disease process. A markedly elevated temperature is seen in acute, severe inflammatory processes. Pathologic lowering of the body temperature is seen in disorders that cause an inhibition of metabolism such as postparturient paresis, neonatal hypoglycemia, the end stages of a chronic disease, or severe septicemia resulting from gram-negative bacteria. There is a normal diurnal variation in body temperature of as much as 0.5° to 1° C (1° to 2° F). In the female there can also be a slight increase in temperature in the days preceding estrus. Neonates are poor thermoregulators and often have a normal body temperature that is 0.5° to 1° C (1° to 2° F) higher than that of adults.

In the evaluation of the thoracic and abdominal cavities, the initial step is the ballottement of the abdomen on the right side.

FIG. 1.4 Schematic representation of the area of the gas ping percussed in association with a right displaced abomasum (RDA) or abomasal torsion.

FIG. 1.3 Schematic representation of areas of gas pings elicited by percussion of the cecum and spiral colon.

FIG. 1.5 Schematic representation of the area of the gas ping percussed in association with a left displaced abomasum (LDA) or gas ping in the rumen.

or kidney can be noted. Palpation of an abnormal swelling or firmness, especially with the elicitation of pain, indicates a problem that must be further evaluated.

The spinal column and ribcage are then palpated; the presence of fractures, enlargement of the costochondral junctions, or the elicitation of pain is noted. Enlargement or fractures of the costochondral junctions are commonly seen in young animals with deficiencies of calcium, copper, or vitamin D.

Auscultation with concurrent percussion by snapping the finger against the thoracic and abdominal walls is the next procedure. Gas trapped within abdominal viscera elicits a “pinging” sound that can be heard with the stethoscope. Localization of these gas pings to certain areas within the abdomen is helpful in determining which alimentary structure is involved (Figs. 1.3 to 1.5). If the cecum is enlarged and gas filled, an abdominal ping can be heard. This can extend caudally to the tuber coxae and cranially through the paralumbar fossa and under the ribcage on the right side (see Fig. 1.3). The diameter of this area can be variable and range from 6 inches (15 cm) in a cecal displacement to 3 feet (1 m) horizontally in cecal torsions. Spiral colon pings are generally localized to the right dorsocranial paralumbar fossa and rarely extend farther forward than the tenth intercostal space. They tend to be round areas 10 inches (25 cm) or less in diameter centered high under the last rib (see Fig. 1.3). Although commonly found in sick cattle that are anorectic, these spiral colon pings have no specific diagnostic significance and can be seen in normal cattle occasionally. Gas pings associated with a right­sided displacement or torsion of the abomasum can extend as far cranially as the ninth intercostal space and caudally into the paralumbar fossa (see Fig. 1.4). The diameter of displace­ments is usually 18 inches (45 cm), whereas that of torsions can be up to 3 feet (1 m). In cases of abomasal volvulus, the animal is usually exhibiting other systemic signs such as increased heart rate, dehydration, depression, scleral injection, and mild colic. In simple right-sided displacements or dilations of the abomasum, the only significant finding may be the small gas ping localized to the abomasum in a cow with depressed appetite and decreased milk production.

On the left side, gas pings can be noted as originating from the peritoneum, the rumen, or a left displaced abomasum (LDA).

The rumen is examined by both auscultation and palpation. It should have a doughy texture with a small gas cap in its

■ TABLE 1.2

■ TABLE 1.3

Normal Resting Heart Rates (Beats/Min) for Adult and Young (sounds can vary over the different areas of the thorax or can be found singularly over the entire lung field. Significant pulmonary pathology may be present in ruminants without any auscultatable abnormalities. Total absence of lung sounds ventrally indicates pleural effusion or pulmonary abscessation with loss of airways. When ventral consolidation of the lung occurs, airway sounds are transmitted well and easily heard ventrally as pipestem sounds similar to those heard over the trachea, whereas percussion reveals a marked increase in ventral lung density. The trachea should also be auscultated. Inspiratory dyspnea and stridor are usually the result of extrathoracic obstructions to airflow (nose, pharynx, larynx, extrathoracic trachea). Pneumothorax can also result in loss of auscultatable airway sounds, which may be absent dorsally or entirely over the entire side if the lung has collapsed completely.

Place the middle finger in the intercostal space and slap the finger with the opposite hand or use a tablespoon and rubber hammer to accomplish percussion of the chest wall to determine the ventral lung border. Percussion is most useful in goats and calves. In sheep the wool precludes effective use of the technique, and in adult cattle the chest wall is often too thick to effectively evaluate changes in percussion tones. The chest is percussed in a dorsal-to-ventral direction, moving caudal to cranial on the chest wall. A change in resonance is noted when the ventral border is reached; a line demarcating this change in resonance is the junction of the diaphragm to the thoracic wall. In the ruminant this line should be described by joining a point at the junction of the 11th rib and the epaxial musculature dorsally to a point at the middle of the 9th rib, then cranially to the point of the olecranon. The cranioventral portion of the percussed thorax is dull because of the heart field (≈3 inches [7.5 cm] above the olecranon in adult cattle; 1 to 2 inches [2.5 to 5 cm] in calves, sheep, and goats). Finding an increased area of dullness in the cranioventral lung field associated with harsh lung sounds would be an indication of lung consolidation as seen in Pasteurella pneumonia. Pulmonary emphysema (atypical interstitial pneumonia) should be con­sidered when the lung field is larger than expected, the animal is dyspneic, and airway sounds are minimal, whereas a ventral border that is markedly elevated and in a straight line could be an indication of pleural effusion. In this case auscultation would reveal decreased lung sounds ventrally and possibly the presence of pleural friction rubs. Acoustic percussion of the lung field can extend into the chest only to a depth of 2 to 2 and 12 inches (5 to 6 cm); therefore lesions within the thoracic cavity that lie deeper than this cannot be percussed.

The next step in the physical examination is to assess for evidence of pain in the ventral portion of the abdomen and thorax. This can be accomplished through the use of the withers pinch test or by ballottement of the xiphoid region. The withers pinch test involves auscultating the trachea while the withers are simultaneously squeezed and pushed ventrally. Painful lesions result in the ruminant resisting normal ventral movement of the spine and/or emitting a grunt or holding its breath when this test is performed. Ballottement of the xiphoid is also done while the trachea is auscultated. The xiphoid region is pushed with a knee or struck with a closed fist, and an elicita­tion of a grunt would indicate pain in this region. The examiner can then ballotte the remainder of the ventral abdomen and thorax to classify the lesion as localized or diffuse. If localized, the region affected should be identified. It should be noted that the animal may kick the examiner during the xiphoid ballottement test; thus proper precautions should be taken.

The subcutaneous abdominal veins are assessed next and palpated along their length for the presence of thickened walls, distention, or pulses. Distention and pulses may be abnormal if they correlate with other clinical evidence of right-sided heart failure. Thickening of the wall or evidence of thrombosis is often a consequence of faulty intravenous injection of irritating substances or of injuries that result in hematomas or abscesses.

If the animal is lame or has postural abnormalities, the feet and legs are palpated next. If the animal is uncooperative, it may be necessary to sedate and/or cast it. If sedation is necessary, it should be performed at the end of the physical examination. Care should be exercised for obvious reasons. The examination consists of comparing one foreleg with the other and then comparing both with the expected norm. The same procedure is followed for the hind legs. Abnormalities in the shape of the claw may be hereditary or may be caused by nutritional deficiencies, poor leg conformation, poor housing, or as a sequela to laminitis. The coronary bands should be palpated for evidence of pain or increased heat. An attempt should be made to pick up all four feet individually and observe the soles and interdigital regions for necrotic areas, areas of bruising or swelling, draining tracts, or presence of foreign bodies. The fetlock, carpal and tarsal, stifle, and elbow joints are all easily accessible and should be examined for swelling, tenderness, edema, heat, instability, and crepitation. Each joint should be tested over its full range of motion, and any elicitation of pain should be noted. Physical findings should be consolidated into a decision as to whether the joint problems are infectious or traumatic. Sheep or goats with acute polyarthritis most com­monly have mycoplasma or chlamydial infection. Chronic joint pain in goats (often with soft tissue thickening and enlargement caused by synovitis) is frequently attributable to caprine arthritis encephalomyelitis. Conformation of the legs should be analyzed because this could contribute to a joint or foot problem. The pelvic girdle does not lend itself to extensive examination; however, one can note symmetry or asymmetry and further evaluate during the rectal examination. Fractures of the tuber coxae, subluxation of the sacroiliac junction, acetabular fractures, fractures of the head or neck of the femur, and dislocation of the coxofemoral joint may all be diagnosed by evidence gained during palpation and observation of the pelvic area. The dislocated or fractured limb is frequently shorter than the normal opposite limb. The tail can also be examined for evidence of fractures, paresis, or paralysis.

The perineal region is examined by noting the external condition of the genitals and rectum. Anal sphincter tone can be assessed, and the presence of vaginal discharge can be noted. In males the testicles, spermatic cord, and epididymis should be palpated for the presence of nodules or areas of fibrosis. The testicular circumference can be measured and compared with what is expected for age and breed. These measurements are noted in Tables 1.4 and 1.5. The perineal part of the penis can be palpated for the presence of hematoma or swelling and pain (cellulitis or abscess). In the female the supramammary lymph nodes can be felt at the attachment of the udder to the perineum. Enlargement of these nodes occurs with mastitis or lymphosarcoma. The udder is palpated for the presence of fibrotic areas, commonly seen secondary to staphylococcal mastitis or associated with Trueperella pyogenes (formerly called Arcanobacterium [Actinomyces] pyogenes) abscesses. The presence of a swollen quarter or quarters with pain and heat may be associated with mastitis caused by gram-negative bacteria. Cold damp areas of skin on the udder that are discolored, necrotic, and possibly sloughing are evidence of gangrenous mastitis. In lactating animals, milk should be present in each quarter

■ TABLE 1.4

Expected Values for the Scrotal Circumference of the Bull at Different Ages⁴

■ TABLE 1.5

Expected Values for the Scrotal Circumference of the Ram at Different Body Weights⁵