Physical Findings

In elephants less than 2000 kg, the heart may usually be clearly auscultated from both the left and right sides. This is aided by having the elephant lift its front leg and placing the stethoscope just cranial to the elbow. Tachycardia, arrhythmias, and murmurs have been reported in progressing EEHV cases, as have changes in respiratory rate. These findings may be related to cardiovascular deterioration, worsening anemia, or pericardial or pleural effusion. Transcutaneous ultrasound evaluation of the heart, thorax, and peritoneum is possible in most juveniles and may be used to identify and monitor effusions. Although no published reports exist of thoracocentesis or pericardiocentesis in elephants, both procedures are theoretically feasible in smaller animals and could be necessary if effusions become severe enough to impede respiration or cardiac output.

Mentation and behavior are subjective, and ideally should be observed by individuals familiar with the elephant. Some EEHV patients are described as lethargic or somnolent.⁷ Others refuse to lie down to sleep. Brain imaging techniques are not currently possible in elephants, but procedures that might distinguish between general malaise and elevated intracranial pressure (ICP) caused by vasculitis include an ophthalmic examination to look for papilledema and retinal hemorrhage, as well as cranial nerve evaluation. In animals suspected to have increased ICP, oxygen therapy and mannitol in conjunction with fluid therapy to correct hypovolemia and maintain blood pressure should be considered. Oxygen may be administered at 10 to 20 liters/min from a portable tank through tubing placed into the trunk if the animal permits it, or in a flow-by manner.⁹ Mannitol, an osmotic diuretic used to treat elevated ICP, has not been evaluated in elephants, but the equine dose might be an appropriate starting point.

Edema, especially of the head, neck, and tongue, may become severe enough to impede breathing, prevent swallowing, and cause skin fissures, although total protein and albumin levels may not immediately correlate with the severity of edema. Colloidal support, oxygen therapy, and diuretics may be helpful. Furosemide has been used in elephants at empirical doses extrapolated from equine data.²¹ It must be used with caution in shocky patients and in patients receiving nonsteroidal anti-inflammatory drugs (NSAIDs).

The soft and hard palates, tongue, and buccal surfaces of the mouth should be examined for oral ulcers or vesicles. Discomfort from such lesions, or from others located in the larynx or esophagus, may contribute to anorexia. The conjunctiva and genital mucosa, as well as the sclera, should be assessed for lesions, injected vessels, and color changes. Cyanosis is a significant finding that ideally should be correlated with a pulse oximetry reading or measurement of Pao₂. Although pulse oximetry may be challenging in elephants, usable probe sites include the finger of the trunk, tongue, upper lip, pinna of the ear, and distal nasal septum. A caveat is that these devices are designed to read the oxygen saturation (Sao₂) of human hemoglobin (Hb), which has a lower oxygen affinity than elephant Hb. Thus, a high Sao₂ reading could, in fact, correlate with a lower Pao₂.¹⁰ Supplemental oxygen should be provided to cyanotic patients and those with low Sao₂ and Pao₂.

Lameness associated with EEHV may be caused by leakage of blood into joints, muscle swelling, or other viral damage. Ruling out nonviral causes of lameness should be attempted. NSAIDs may relieve discomfort but, to avoid nephrotoxicity, they should be used at the lowest dose possible and only in hydrated animals. Flunixin meglumine appears to provide significant relief, but other NSAIDs can be used, as can other classes of analgesics. Stomach protectants or acid blockers might be warranted if NSAIDs are given. Their usage in elephants is empirical.

Abdominal pain, another nonspecific sign, is commonly reported.⁷ Decreased borborygmi, inappetance, or scant manure may be caused by impaction from dehydration or viral damage to the gastrointestinal (GI) tract. Diarrhea may also be caused by viral injury. However, because elephants are prone to a variety of nonviral causes of colic, even in a confirmed EEHV case, other diagnoses should be considered. Treatment of colic signs is symptomatic.

Decreased urine output and/or the presence of blood or protein in the urine may indicate renal compromise caused by inadequate circulation. Except for very young calves, elephants do not concentrate their urine very well, and specific gravity does not indicate hydration status.²⁶ Standard signs of dehydration such as sunken eyes or decreased skin turgor are rarely observed in elephants. The patient’s water and milk consumption should be assessed to correlate input with output. Sick elephants should be weighed daily, if possible.

EEHV patients often present with low-grade fever. Normal fecal ball temperatures are 35° C to 37° C (96.8° F to 98.6° F).¹ A subcutaneous microchip that measures body temperature has been developed for horses and is currently being tested in elephants. Fever does not necessarily require treatment, but is a useful monitoring tool.