Hand-raising Orphan Asian Elephants
Chapter 8: Medical Problems & Treatment
By Susan K. Mikota DVM
With contributions from Vijitha Perera and Willem Schaftenaar
Sections in this chapter include the following:
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Introduction
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Anorexia (loss of appetite)
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Aspiration of formula
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Bloat
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Colic
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Constipation
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Dehydration
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Dental problems
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Diarrhea and other GI problems
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Dry skin
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Elephant Endotheliotopic Herpes Virus (EEHV)
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Failure of passive transfer of antibodies
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Fractures
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Impaction
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Metabolic bone disease
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Parasites
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Sepsis (septicemia, systemic infection)
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Sunburn
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Umbilical hernia
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Umbilical infection
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Wounds (including snares)
Introduction
This chapter includes diseases and conditions that may be encountered when hand-raising elephant calves. Some are minor and can be easily managed; others are more serious and life-threatening. Certain conditions may be obvious (e.g. diarrhea) while others may be more difficult to identify and treat (e.g. metabolic bone disease).
Hand-raised elephant calves can deteriorate very quickly so any changes in health should be taken seriously. The standard veterinary approach is to 1) review the history 2) perform a thorough physical exam 3) conduct laboratory tests 4) develop a differential diagnosis (a list of possible causes), 5) use all of the information to determine a diagnosis or tentative diagnosis, and 6) develop and institute a treatment plan.
Daily observations by caregivers are critical to the calf’s health and well-being. Caregivers should be familiar with the signs of health and illness listed in Tables 8.1 and 8.2.
Photo credit: Susan Mikota
A daily checklist may be helpful and can be posted in the nursery area to remind staff to perform daily observations. An example is provided in Table 8.3.
Gastrointestinal problems are common in young orphan calves and may manifest as anorexia, bloat, constipation, straining, or diarrhea. It is important to perform a fecal examination to determine if parasites are present and to administer appropriate medications.
There is increasing awareness in both human and animal medicine of the importance of a healthy microbiome (beneficial organisms) in the gastrointestinal (GI) tract. Elephant calves will typically consume dung which is a normal behavior that helps to establish a healthy flora in the GI tract. This behavior should be encouraged and access to dung from healthy adults (Salmonella-free) should be provided. The administration of probiotics may be helpful although there is limited information about this topic in elephants. The microbiome is discussed in further detail in Chapter 5 (Digestive Physiology and Gastrointestinal Flora).
Anorexia (loss of appetite)
A decreased or complete loss of appetite can be a serious sign so it is important to determine the underlying cause. Ideally a veterinarian should conduct a thorough physical examination and obtain a complete history.
Questions to consider: Does the calf have a fever? Pain? Loose feces or diarrhea? Constipation? Has there been a change in the diet or in the calf ‘s environment? Has the staff changed? Answers to these questions may help to identify the cause or signal the need for diagnostic tests such as a fecal exam for parasites or a CBC and chemistry panel to determine if infection is present.
Vitamin B12 is an appetite stimulant and can be given in mild cases or while waiting for lab results.
Aspiration of Formula
Improper bottle feeding can result in the inhalation of milk into the lungs. This causes inflammation, damages lung tissue, and can result in aspiration (inhalation) pneumonia.
Immediate signs of aspiration may include:
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Coughing or choking sounds during bottle feeding
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Fluid coming out of the nostrils
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An excess amount of formula overflowing from the mouth immediately after feeding
Clinical signs of pneumonia may include one or more of these signs:
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Loss of appetite
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Weight loss
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Fever
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Lethargy, depression
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Difficulty breathing
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Bluish color to mucous membranes (indicating poor oxygenation)
Inhalation pneumonia is a serious condition and requires prompt veterinary examination and treatment. The veterinarian will listen to the lungs and may recommend radiographs. A radiograph of the chest is probably feasible only in calves under six months of age. Broad-spectrum antibiotics are typically prescribed. Additional treatments may include oxygen therapy, anti-inflammatory medications, bronchodilators, and nebulization.
Aspiration pneumonia can be life threatening or fatal and is best prevented by good feeding practices:
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Never give milk faster than the calf can swallow. See Figure 8.1.
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Make sure that the hole in the nipple is appropriate. It should not be so large that milk just flows out freely. Check before each feeding to make sure it has not enlarged or split.
Figure 8.1 Avoid milk overflowing during feeding as this can be a risk for aspiration pneumonia. Check that the nipple hole is not too large. Photo credit: Susan Mikota
Bloat
Bloating is due to excess gas in the intestines. Signs may include a visibly distended abdomen, straining, unusual posture, discomfort, and possibly difficult breathing if severe. Bloat can be diagnosed by tapping on a rib while listening with a stethoscope or even by placing your ear on the abdominal wall. If bloat is present, a so called “steel band” sound will be heard as the gas-filled gut will act as a drum.
Observe to make sure that the calf is passing feces. The absence of feces can be a sign of impaction.
Bloat is usually caused by a change or an imbalance in the diet that disturbs the normal gastrointestinal flora. In calves that are still on the bottle, avoid sudden formula changes. Provide access to dung from a healthy adult elephant for several days. It is normal for calves to ingest dung and this helps to establish a healthy gut flora.
In calves that are eating solid food, underlying causes may include a sudden diet change, over-feeding fruits, or feeding lush forages that are low in fiber (immature legumes like clover and alfalfa).
The best approach is to stabilize the diet. Eliminate or minimize fruits (which should only be given as a treat) until the bloat resolves then re-introduce gradually. Encourage the calf to walk around which may help gut mobility. Adding honey to the diet temporarily seems to have a soothing effect on the GI tract.
There are a number of veterinary products to treat bloat in domestic ruminants, but their use in elephants has not been reported.
Colic
Colic is a broad term for a variety of conditions that cause abdominal pain.
A detailed presentation on Colic, Constipation and Impaction is found here.
Constipation
Constipation is a decrease in bowel movements or the passage of hard dry feces.
Constipation can occur as a result of a diet change, contaminated food, excess fiber, ingestion of foreign material, a stressful event, or other causes. The calf may strain to defecate but only scanty or no feces will be produced. The calf may be lethargic and may refuse to eat. Rubbing the hindquarters is another sign. Check the feces for the presence of long fibers or sand.
Gentle warm water enemas are the best treatment. Refer to the Chapter 9 (Medical Procedures) for instructions.
Warm compresses applied to the abdomen and gentle massage may help if the calf is cooperative. Encourage the calf to move around on land or swim. Sometimes giving the calf a bath will encourage defecation.
Giving fruit juice (especially tamarind juice) may help.
Stool softeners, containing docusate sodium are available as veterinary formulations (oral solutions, enema solutions) for cattle, horses, and dogs.
Similar products for human use can be found in many pharmacies (capsules or syrups) and can be mixed with food. Drugs that speed gastric emptying and stimulate peristalsis (movement of the intestines) should be used with caution as they have the potential to cause an intestinal rupture if there is a blockage.
Bisacodyl is a stimulant (purgative) laxative. Dulcolax is a common brand name. This drug should not be used if an impaction (intestinal blockage) is suspected. Bisacodyl is available in oral form and as a rectal suppository.
A traditional therapy used in Sri Lanka is to feed tamarind combined 1:1 with epsom salts (Silva and Dangolla, 2006).
Mineral oil (also known as liquid paraffin) acts as a laxative by lubricating the intestinal mucosa and fecal material. Extreme care must be used when administering mineral oil orally to prevent aspiration into the lungs which can result in lipid pneumonitis (inflammation of the lungs). In domestic species, mineral oil is generally administered via a stomach tube. This should only be attempted in elephant calves by an experienced elephant veterinarian. The dose for domestic (cow) calves is 60–120 ml. For elephant calves, mineral oil can be safely placed on food items. It is tasteless.
Pain medications may be indicated if the calf is experiencing a great deal of discomfort. Flunixin is a commonly available veterinary NSAID (non-steroidal anti-inflammatory drug) that can be helpful in these situations. It is best to limit its use to three days or less.
In some cases rectal or IV fluids may be recommended by the veterinarian.
A detailed presentation on Colic, Constipation and Impaction is found here.
Dehydration
Dehydration occurs when there is a loss of body fluids or inadequate fluid intake. Loss of body fluids can occur with injuries or diarrhea. Dehydration can be a serious issue and should be corrected as soon as possible.
Simple test for dehydration in calves (recommended by Dr. Khyne U Mar):
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Gently pinch the skin on the shoulder blade, loin, or brisket with two fingers so that it makes a “tent” shape.
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Release the skin.
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Hydration is normal if the skin springs back to its normal position in one to three seconds.
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If the skin is slow to return to normal, the calf may be dehydrated.
Dark concentrated urine, reduced urine output, or dry hard feces can indicate that hydration is inadequate.
Assessing the condition of the mucous membranes and the capillary refill time (CRT) can help to determine the degree of dehydration. The CRT is a quick test to evaluate blood flow. You can perform it on yourself to demonstrate by applying pressure briefly to a nail until it blanches (turns white). When you release the pressure, the pink color should return in 1–2 seconds.
In elephants we can check the CRT using the mucous membranes inside the mouth. Press on the mucous membranes until they blanche, release, and note the time for the color to come back. Normal is 1–2 sec.
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Mild dehydration (5–7%): the mucous membranes will be dry, the CRT will begin to slow and the calf may seem depressed.
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Moderate dehydration (8–10%): the CRT will be 2–4 seconds and depression will be more pronounced.
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Severe dehydration (>10%) the CRT will be ≥ 5 seconds and the calf may be moribund (at the point of death).
The hematocrit and total protein values can be used to evaluate hydration status and response to treatment. Both of these values may be elevated with dehydration.
If dehydration is due to diarrhea, there is a tendency to dilute the formula but this can actually make the diarrhea worse. It is better to give a separate bottle of water 30-60 minutes after feeding formula. If the dehydration cannot be corrected quickly, fluids may need to be administered rectally or IV (in severe cases). Refer to Chapter 9 (Medical Procedures).
Dental Problems
Over the course of its life, an elephant will have 24 molar teeth. Unlike most mammals, the teeth emerge horizontally rather than vertically. As each molar wears down and sections break off, it is replaced by the emerging molar pushing forward. See Figures 8.2 and 8.3 showing the mandible (lower jaw) of an elephant. Males have tusks (technically an incisor tooth); females may have smaller tushes which may not be visible unless the margin of the tusk sulcus is lifted.
Table 8.4 below shows molar the molar number with its corresponding number of lamellae, the approximate eruption time for each molar, and the approximate age that replacement of each tooth occurs (Kalita, S.N. et al. 2003).
Molar Problems
Potential molar problems include malalignment, abnormal wear, abscesses, or fractures.
Molar problems are uncommon in young elephants. The eruption of a molar may be painful, but this is usually a transient problem that resolves by itself. During the eruption of the first molar, usually around the age of four months, the calf is still fully dependent on milk. When six months old, the second molar may become visible in the mouth. The third molar appears at three years of age.
If, for still unknown reasons, the formation of a molar (while still in the alveolus) is disturbed, a misshaped molar may erupt, which will often rotate and cause mastication problems. This condition, however, has not yet been reported in young elephants.
Click on image above to open PDF.
Click on image above to open PDF.
Figure 8.2 Mandible (lower jaw) of an elephant illustrating molar eruption
Figure 8.3 Xray of an elephant calf skull showing how the teeth emerge. Photo credit: Christian Wenker
Tusk Fractures
Tusk fractures can occur from trauma. Management depends on the type of the fracture and the options for treatment.
In very young elephants, a conservative approach is usually sufficient. Removing the sharp edges of the tusk remnant is important to prevent damaging the sulcus tissue (Figure 8.4 below). This can be done by hand-filing the edges. If the pulp tissue is not exposed, this treatment suffices.
When the pulp tissue is exposed, the pulp should be cleaned twice a day by gently flushing it with large amounts of saline solution. Don’t put too much pressure on the flushing stream, as that may force bacteria into the pulp tissue. After flushing with saline, flush with a diluted iodine or chlorhexidine solution. The pulp tissue has a strong regeneration potential, but there is always a risk that microbes will become trapped in the space behind the newly formed secondary dentine. Maintaining conservative treatment for a long period is preferred.
The second method to treat a fractured tusk in a young elephant is a partial pulpectomy and filling. For this procedure, see: Tusk fracture | Elephant Medicine.
Blind Tusk
A blind tusk is a tusk that fails to penetrate through the skin. It is seen as a subcutaneous swelling at the place of the expected eruption. It may be painful and give some discomfort. If very painful, a skin incision may relieve the pain and facilitate the further growth of the tusk.
Sulcus Infection (Pericoronitis)
When a tusk has just erupted, the sulcus area (around the base) may become infected. A purulent infection of the skin can be seen in Figure 8.4 around the newly erupted tusk. This condition should be treated like a skin wound by flushing and disinfection. If needed, more space should be created by making a small incision in the skin.
A pericoronitis can also be the result of trauma such as when sharp edges of a fractured tush or tusk cause small sulcus lesions. Another cause of pericoronitis is an infestation with the stomach bot fly. This fly usually deposits her eggs around the mouth of the elephant. The larvae will find their way to the mouth, but sometimes they get lost and invade the sulcus of the tusk. If that is the case, proper cleaning and flushing of the sulcus is the treatment of choice.
Excessive Dental Wear
Excessive wear of a tusk can be caused when the elephant displays stereotypic behavior and rubs the tusk frequently against a steel bar, concrete wall, or rock. When this is done very intensively, the pulp can become exposed or the tusk can fracture.
Figure 8.4 Pericoronitis caused by sharp edges of a fractured tusk. Photo credit: Willem Schaftenaar
More information about dentistry in elephants: Dentistry | Elephant Medicine
Diarrhea and Other Gastrointestinal Problems
Diarrhea can be a serious problem in young calves. It may be caused by diet changes, bacterial or viral infections, parasites, or stressful environmental changes.
Loose feces occur commonly in hand-reared calves so it is important to distinguish when it is a problem that requires treatment. The primary caregivers should observe the feces every day and determine what is typical for an individual calf while in a healthy state. The frequency and characteristics (formed, loose, very loose, watery) should be recorded in the written record daily. Images of normal, loose, and diarrheic calf feces are shown in Figures 8.5, 8.6, and 8.7.
Watery diarrhea is of greatest concern especially if other signs of illness such as listlessness, loss of appetite, weakness, dehydration, or pain are present.
Figure 8.5 Normal calf feces. Photo credit: Bhaskar Choudhury
Figure 8.6 Loose calf feces
Figure 8.7 Diarrheic calf feces. Photo credit: Bhaskar Choudhury
In cases where the calf is showing any of these signs it is prudent to collect samples for diagnostic tests including a fecal parasite exam and aerobic and anaerobic fecal cultures to rule out intestinal pathogens such as Salmonella, E. coli, Clostridium, or Pseudomonas. Collect blood for a CBC and serum chemistry panel if possible.
If loose stool is the only sign and the calf is not showing any other serious issues, altering the formula temporarily may solve the problem. Options include (Emanuelson, 2006):
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For one day replace the formula with boiled rice water or an electrolyte solution (products used for human babies with diarrhea and available in the markets).
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For each feeding alternate the regular formula with an electrolyte solution for 1-3 days.
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Alternatively, concentrate the formula slightly using 10-15% less water per feeding, and provide extra water or electrolyte solution bottles 30-60 minutes after each feeding.
Results of diagnostic tests may dictate that anti-parasitic drugs or antibiotics may be indicated. Antibiotics should not be used unless clearly indicated as they can upset the normal intestinal flora.
In cases where diarrhea is severe and the calf is dehydrated, fluids may need to be administered orally, rectally, or IV. Refer to Chapter 9 (Medical Procedures).
Dry Skin
Dry skin can be irritating, causing the calf to rub or scratch. Warm water baths a few times a week followed by topical oil treatments may help (neem, sesame, or coconut oil for example). Access to an area for dust bathing is also recommended.
Elephant Endotheliotropic Herpes Virus (EEHV)
EEHV-hemorrhagic disease (EEHV-HD) is a devastating disease that can affect captive or wild elephants. It is caused by a group of herpesviruses unique to elephants named Proboscivirus. In Asia, cases have been reported in India, Thailand, Laos, Cambodia, Malaysia, Indonesia, Myanmar, and Nepal. There are nine different (sub)species. Asian elephants are most often affected by EEHV 1A, EEHV 1B, EEHV4 and EEHV5, of which EEHV1A has caused the vast majority of fatalities.
Young elephants 1–8 years of age are at greatest risk. Most (if not all) adult elephants have been infected with EEHV without associated clinical illness (Hoornweg, 2021). Asymptomatic adults can shed herpes virus in trunk, oral, conjunctival, and vulva secretions.
Elephants <1-3 years of age may be protected by the presence of maternal antibodies (Hoornweg, 2024). At birth the calf has EEHV-antibody levels similar to the levels of the mother. During the first year of life the antibody level remains high, provided that the calf is naturally nursed. In the next two years these antibody levels decline remarkably slowly. It is generally accepted that the calf enters the EEHV-HD risk phase between the age of 1 and 1.5 years.
In just a few cases it has been observed that antibody levels in a hand-reared calf decline earlier than in a naturally reared calf. This raises the question whether the elephant’s gut is able to absorb EEHV-antibodies that are present in the mother’s milk. The presence of EEHV-antibodies has been confirmed (Pers. Comm. Willem
Schaftenaar, 2024). Further studies are needed to verify this hypothesis.
During this period in which the calf is still protected by maternal antibodies, it should be exposed to the virus in order to build up its own, lifelong immunity. Close contact of calves in the range of 1-1.5 years with EEHV-shedding elephants should therefore be encouraged (Hoornweg, 2022).
Early clinical signs of EEHV-HD may include lethargy, loss of appetite, alterations in sleep, gastrointestinal signs (constipation or diarrhea), stiffness, or lameness.
More advanced signs include a rapid heart rate, edema (swelling) of the head, neck or limbs, bruising or hemorrhages, and cyanosis (blue appearance) that is most noticeable on the lateral side of the tongue. See Figures 8.8, 8.9, and 8.10.
EEHV-HD has a rapid course (1–7 days) and a 70% or greater mortality so early recognition and treatment are essential. EEHV kills by damaging blood vessels which causes hemorrhages in multiple organs (especially the heart, liver, and tongue). Hemorrhages in the heart muscle lead to heart failure, shock, and death.
A positive PCR test on an EDTA blood sample will confirm the presence of the virus. Whether the elephant is actually ill from this virus needs to be confirmed by the presence of clinical signs or the outcome of a hematological examination (decreased number of monocytes and thrombocytes). However, there are only a few labs in Asia that can perform this qPCR-test. EEHV testing laboratories are listed here.
Figure 8.8 Edema of the head, neck, and forelegs of a 3-yr-old Asian elephant calf with EEHV-HD Courtesy of Khajohnpat Boonprasert, Chiang Mai University, Thailand.
Figure 8.9 Small hemorrhages on the tongue of a 3-year-old Asian elephant calf with EEHV-HD. Courtesy of Khajohnpat Boonprasert, Chiang Mai University, Thailand.
Figure 8.10 Cyanosis (blue color) of the tongue due to heart failure in an asian elephant calf with EEHV-HD. Photo credit: Willem-Jan Kitslaar, Amersfoort Zoo, The Netherlands.
Warning: Treatment should not be delayed if EEHV is suspected.
Treatment is intense and includes rectal and/or IV fluids, antiviral drugs, anti-inflammatory drugs, antibiotics, and plasma transfusions. Multiple sedations may be needed. Even when treatment is started promptly, many calves die. It is essential to count monocytes and thrombocytes, as these cells can drop dramatically. The decrease of these two cell types is an indication for the severity of the disease.
Detailed treatment guidelines can be found in Guidelines for Management Elephant Endotheliotropic Herpesvirus (EEHV) in Asia, 2nd edition.
The veterinarian and key staff involved with hand-raising elephant calves should be familiar with this disease and treatment. A hard copy of the Guidelines should be kept at the facility and should be readily available.
As time is critical when this disease strikes, medications and supplies needed for EEHV-HD treatment should be either stocked or pharmacies identified where they can be promptly procured.
For calves in high risk age groups (1–8 years), it is advisable to establish individual baseline CBC values and then monitor weekly or every other week observing for decreases in the white blood cell count (especially decreased numbers of monocytes) and/or decreased platelets. If monocytes and platelets decrease suddenly, EEHV-HD should be suspected and treatment considered.
A list of EEHV publications can be found on the Elephant Care International Database.
Failure to Provide Colostrum
Passive immunity is the transfer of antibodies to a newborn animal either prenatally (before birth) via the placenta or postnatally (after birth) via the ingestion of colostrum. Colostrum is the first milk secreted after birth. It is rich in immunoglobulins (antibodies) that help to prevent disease in the first few weeks of life while the neonate’s own immune system is developing. In domestic species that depend on postnatal antibody transfer (cows and horses for example), newborns that do not receive colostrum are more likely to experience medical problems and have higher mortality. This is called failure of passive transfer. However, there are indications that this might work differently in elephants.
Two studies have demonstrated that maternal to fetal antibody transfer does occur prenatally via the placenta in elephants (Nofs et al., 2013; McGee et al., 2014). At birth the antibody levels in the calf are as high as in the mother. In mother-reared calves, they remain high for up to 12 months. This is much longer than in any other mammalian species and suggests that uptake of antibodies in the milk from the gut might be a normal physiological process in elephants. This knowledge must encourage us to provide elephant milk as frequently as possible during the first year of the calf’s life.
Our knowledge of the elephant’s immune system is not complete and while it has been shown that prenatal antibody transfer occurs in elephants, we don’t know if colostrum also plays a role in the process of antibody transfer. To provide the best possible care to a newborn elephant calf that fails to nurse, it is prudent to collect colostrum from the mother and to feed it to the calf using a bottle. It is possible to collect colostrum by milking by hand or by using a human breast pump. Refer to breast milk collection procedures in Chapter 9 (Medical Procedures). Whenever possible, elephant milk from any other lactating elephant should be provided during the first year of a calf’s life.
For hand collection the procedure is similar to milking a goat. Use the thumb and forefinger to squeeze the teat at the top and then squeeze the other three fingers in succession (Emanuelson, 2006).
Offer as much colostrum as the newborn will take at frequent intervals. They may not ingest more than ~0.5 liters at a single feeding. Remember that in other mammalian species, colostrum can only be absorbed within the first 24-36 hours of life. This may or may not be true for elephants.
If colostrum or elephant milk is not available, plasma can be given to the calf. Intravenous administration of plasma is quite an invasive procedure that not only stresses the immune system, but may also result in damaging the veins used for the infusion. To avoid these negative effects, plasma can best be given orally during the first 2-4 days in portions of 100-200 ml, 3-4 times per dayBased
The procedure for collecting plasma is included in the Guidelines for Management Elephant Endotheliotropic Herpesvirus (EEHV) in Asia, 2nd edition.
Foreign Body Ingestion
Calves are curious and may ingest foreign materials like plastic bags, ropes, or various items found lying around or in garbage. These foreign materials can cause impactions in the digestive tract that can be deadly. It is best to prevent this situation by keeping the nursery area clean and free of objects the calf might ingest. If a foreign body is suspected, veterinary assistance is needed. (See also this video of the removal of a stick from the trunk of a young elephant).
Fractures
Fractures can occur in any of the long bones from trauma and are best prevented by keeping the calf in a safe environment free of objects that could potentially cause injury. Fractures can also be a sign of metabolic bone disease (discussed below). Fractures require veterinary intervention. Radiographs are advisable.
Closed fractures have a much better prognosis for healing than open fractures. The first option for closed fracture treatment is providing a water basin in which the elephant can find comfort. The water should be deep enough to reduce the bearing weight on the affected leg. There are examples of elephants staying in such a basin for several weeks until the fractured bones had healed completely. The elephant should be able to walk out of the basin whenever it wants to. This form of hydrotherapy is easy applicable and provides pain relief from the start. If the fracture ends are distracted to such a degree that reapposition and fixation are essential for normal locomotion, the use of external or internal fixation should be considered.
The location of the fracture and degree of bone displacement will determine treatment options. Fractures of the lower limbs (tibia, radius, ulna) may be amenable to external fixation (splints or casts). A two-year-old calf at the Pinnawala Elephant Orphanage in Sri Lanka that sustained an oblique fracture of the radius and ulna was successfully treated by applying a fiberglass cast and aluminum plates (Karunarathne et al., 2017). Details and images can be found here: https://www.asesg.org/PDFfiles/2017/Gajah%2047/47-40-Karunarathne.pdf
Surgery is more likely to be recommended for humeral or femur fractures as it is difficult to keep these bones stable using external devices. However, in one case, a three-year-old 600 kg calf with a fracture of the distal femur was successfully treated by immobilizing the limb with continuous knitting bamboo splints and heavy cotton padding that was changed on alternate days due to urine soaking. The calf was placed in a sling for an hour twice a day to encourage blood circulation and prevent pressure atrophy. The legs were also massaged. The calf was able to stand and walk after three months (Sarma et al., 2006).
Impaction (intestinal obstruction)
Ingestion of dirt, clay, or sand, excessive high fiber foods, or the presence of a foreign body (e.g. plastic) that becomes impacted (stuck) in an area of the GI tract may result is a partial or complete obstruction. Signs are similar to constipation and may include loss of appetite, pain, abdominal distension, scanty or no feces, and abnormal postures. This is a more serious condition that can result in dehydration, electrolyte imbalances, endotoxic shock (caused by bacteria), circulatory collapse, gut wall necrosis, rupture of the gut wall, and death.
Prompt treatment is essential. Relieving pain with injectable drugs such as flunixin or butorphanol is the first step. If the calf will take food, mineral oil mixed with bran can be given. Relaxation of the gut spasm can be obtained by the administration of Buscopan Compositum (contains 4 mg butylscopolamine bromide and 500 mg per ml; the dosage 5 ml/100 kg BW i.v. or i.m.). If the obstruction is distal (towards the end of the GI tract), warm water enemas may help. If the calf will not drink or is dehydrated, IV fluids may be needed (Dumonceaux, 2006). However, rectal fluids are often more effective as large volumes can be easily given without the unpleasant experience of IV infusions for the calf.
As mentioned above in the section on constipation, drugs such as bisacodyl (brand name Ducolax) that speed gastric emptying and stimulate peristalsis (movement of the intestines) should not be used if an impaction is suspected as they may cause an intestinal rupture.
A detailed presentation on Colic, Constipation and Impaction is found here.
Metabolic Bone Disease (Rickets)
Metabolic bone disease encompasses several diseases that cause bone abnormalities. See Figures 8.11, 8.12, and 8.13. In young growing calves, it is also called rickets and is almost always a nutritional disorder resulting from imbalances in calcium, phosphorous, magnesium, and/or Vitamin D. Protracted diarrhea may contribute to malabsorption of key nutrients so should be corrected as soon as possible. A number of cases have been reported in the literature (Ensley et al., 1994; Kajaysri et al., 2003).
Figure 8.12. Fractures in the front leg of a calf that died of metabolic bone disease. The fractures are circled. The image on the left is a CT scan. Courtesy of Leibniz Institute for Zoo and Wildlife Research, Berlin, Germany.
Figure 8.11 Metabolic bone disease (rickets) in a young calf. Note the bowing of the legs. Photo credit: Susan Mikota
Xrays of all four limbs will help to determine the severity of the problem. The bones may be deformed and appear more translucent.
A number of studies have looked at calcium metabolism or have attempted to identify biomarkers in the blood for bone metabolism but to date there is no readily available test that has been validated (Kilgallon et al., 2008; van Sonsbeek et al., 2011; Van Sonsbeek et al., 2013; Arya et al., 2015; Takehana et al., 2018; Takehana et al., 2019; Takehana et al., 2020).
Early correction is essential. Review the diet paying particular attention to the minerals mentioned above. Compare the diet being fed to the recommendations in Chapter 4 (Feeding Milk) and make corrections as needed.
Figure 8.13 Xray of a bottle-fed calf with metabolic bone disease. Note thinning of bone cortices and pathological fractures. Courtesy of Dr. Charles Reid, Kennet Square, Pennsylvania.
Ensure the calf has daily exposure to sun (for Vitamin D production in the skin). If the legs are starting to bow, supportive bandages or casts may help. Because this is serious problem that can result in the death of the calf, seek advice from experienced veterinarians and nutritionists.
Routine xrays every 4–6 weeks beginning at 2–3 months of age may identify problems early and allow corrective actions to be taken before the condition progresses.
Parasites
See the image gallery (Plate 8.1) below for gross parasite images. Images of parasite eggs under the microscope can be found in Chapter 9 (Medical Procedures ). For a complete review of elephant parasites see (Fowler, 2006). For more information see Parasitology | Elephant Medicine.
External parasites (Ectoparasites)
Regular bathing and access to an area for dust bathing can help control external parasites.
Lice
Lice (Haematomyzus elephantis) are small wingless insects about 3-mm long. They are transmitted between elephants by close body contact. Lice may be found behind the ears, at the base of the tail, or anywhere there are folds in the skin. Lice can cause dermatitis and dry scaly skin. Elephants may be restless with frequent scratching. If lice are present around the eyelids, scratching may cause damage to the cornea. Frequent bathing, making sure to scrub behind the ears and other likely sites can help to remove lice. Flumethrin, a pyrethroid insecticide commonly used in dog and cat flea products, can be used topically. Heavy infestations can be treated with ivermectin given SQ or orally (Karesh and Robinson, 1985). Ivermectin kills nymphs and adults but not eggs (also called nits) so treatment should be repeated in 3–4 weeks when the next batch of eggs hatch. Lice are host-specific.
Fleas
Fleas are wingless insects about 1.5–4 mm in size. Fleas are not host specific so fleas from dogs or cats may infest elephants. Elephants can become infested with fleas by walking through an area contaminated with flea eggs or pupae or by close body contact with other elephants that have fleas. Fleas may cause the elephant to scratch and swelling and redness may be seen at sites where fleas have bitten. Fleas are blood-sucking parasites so a heavy infestation could cause anemia in a small calf. Ivermectin can be administered but attempts should also be made to clean up the environment and keep flea-infested dogs or cats away.
Horseflies (Tabanids)
Horseflies are large blood sucking flies. They are especially active on hot, bright, humid days. Their bite is painful and irritating and may result in the formation of nodules on the surface of the skin. Tabanids are the intermediate host for Trypanosoma evansii, a blood parasite that causes trypanosomiasis (also called surra or thut) in elephants (Fowler, 2006).
Screwworm flies/maggots
Screwworm flies (Chrysomya bezziana) lay eggs in and around open wounds. When they hatch, the maggots burrow and feed on tissue. Maggot-infested wounds should be flushed and maggots removed manually. Hydrogen peroxide or ether will coax maggots from deeper wound crevices. Zoosamex spray (Wokwel Ptd. Ltd. Singapore) has been used in Sri Lanka to kill maggots that have penetrated deep into tissue (Silva and Dangolla, 2006). Remove necrotic (dead) tissue and thoroughly clean the wound at least daily.
Ticks (Amblyomma sp.)
Ticks may be found behind the ears, on the shoulder or upper hind leg or in the perineal area (near the anus). They should be removed manually.
Internal parasites (common)
Elephants are affected by three major groups of parasites:
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Nematodes: roundworms like strongles, strongyloides, and hookworms
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Trematodes: flatworms like liver flukes (Fasciola elephantis)
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Cestodes: tapeworms like anoplocephala
In healthy wild elephants parasites often live in balance with their hosts without causing any obvious harm. However, any number of environmental stressors can upset this balance and result in clinical disease even in adults.
Orphan calves are often under tremendous physiological and/or mental stress resulting from lack of food, separation from the herd, or injuries. So it is important to determine what parasites they are harboring and to administer appropriate anthelmintic (de-worming) medications. Parasites that may not have been a problem for a healthy calf can be deadly for a traumatized orphan.
At the Elephant Transit Home in Sri Lanka, if the eggs per gram count of nematodes is high, calves are dewormed using fenbendazole, albendazole, levamisole, or ivermectin. If there are Fasciola eggs in the feces, they are treated with triclabendazole, and if Anoplocephala eggs are found they are treated with praziquantel.
The prevalence of various parasites may vary with geographical location and environmental factors. Flukes, for example require water and the presence of an intermediary host (snails).
General signs of parasite infections include weakness, poor skin and body condition, diarrhea, poor appetite, a tendency to eat mud, and in the case of blood sucking parasites, anemia. Submandibular or ventral edema may be seen.
Some adult parasites may be seen in the feces but most reside deep within the intestinal tract. It is always advisable to perform a fecal examination to look for parasite eggs under the microscope.
Nematodes
Strongyles. There are several species of parasites that have strongyle-type eggs. Other than for research purposes, it is not important to determine the genus and species. Adults are found in the stomach, small or large intestine, or cecum depending on the species. Larvae hatch from eggs passed in the feces and elephants become infected by eating larvae on forage. Any of the broad spectrum anthelmintics including albendazole, fenbendazole, mebendazole, or ivermectin should be effective.
Strongyloides. Strongyloides are small nematodes with two forms – a parasitic form that lives in the intestinal tract and a free-living form found in the soil. Elephants become infected by ingesting infective larvae or larvae may penetrate through the skin. From the intestine, larvae may migrate to other tissues including the mammary gland and may be found in milk, another means of transmission to calves. Strongyloides are usually harmless in adults but in orphans who are weak or sick they may cause a problem. Any of the broad spectrum anthelmintics including albendazole, fenbendazole, mebendazole, or ivermectin can be used.
Hookworms (Bunostomum spp.) Hookworms are small and round and live in the intestines. Elephants are infected by ingesting larvae on forage or when larvae penetrate skin. They are blood sucking parasites so can cause anemia and be very harmful to young calves. Any of the broad spectrum anthelmintics including albendazole, fenbendazole, mebendazole, or ivermectin can be used.
Filaria parasites. Filaria are a group of nematodes that live in the tissue of vertebrates; filariasis refers to the presence of microfilaria in blood and tissues. Indofilaria spp. cause a cutaneous filariasis that results in 1–2 cm nodules on the sides, lower abdomen, and limbs (Chandrasekharan, 2022). Stephanofilaria spp. cause lesions on the back and ventral areas (Bhattacharjee, 1970) or on the feet (Tripathy et al., 1989; Tripathy and Das, 1992). Microfilaria can be seen in blood that oozes from ruptured nodules and also in the peripheral blood. Other clinical signs of cutaneous filariasis may include restlessness, dry skin, and submandibular or ventral edema. Diagnosis is by observing the motile parasites on a blood smear that is best collected between 9 PM and 3 AM (Mar, 2006). Heavy infections can be treated with ivermectin given every 4–6 months (Mar, 2006).
Trematodes
Flukes. Elephants can be infected with Fasciola jacksoni unique to elephants, or Fasciola hepatica common to domestic livestock. Adult flukes live in the bile ducts. Eggs are passed in the feces and must be deposited in water for the next phase of the life cycle that also requires snails which act as an intermediary host. Elephants become infected by ingesting water or forage harboring metacercaria, the infective stage.
Acute clinical signs include anorexia, constipation, diarrhea, anemia, icterus (yellow color of mucous membranes), anemia, and death. The chronic form is characterized by anemia, anorexia, weight loss and either constipation or diarrhea. Mucous membranes may be pale or icteric and ventral edema may be present (Fowler, 2006).
Flukes have characteristic eggs. Because fluke eggs are heavy, sedimentation vs. flotation techniques may be needed for diagnosis. Albendazole, trichlabendazole, or oxyclozanide can be used for treatment which should be repeated in 45-60 days. The first two drugs are preferred as oxyclozanide has been associated with side effects.
Paramphistomes. Paramphistomes are flatworms/flukes with a life cycle similar to Fasciola. There is very little known about this parasite in elephants in the literature. It is commonly a problem in ruminants (stomach or rumen fluke). Paramphiostomes have a similar life cycle to Fasciola and should be susceptible to the same anthelminitics.
Cestodes (Tapeworms)
Anoplocephala. Anoplocephala are large flat segmented tapeworms that live in the intestines. Tapeworm segments can sometimes break off and can be seen grossly in the feces. Elephants pass tapeworm eggs in the feces which are ingested by mites in which the egg matures into a cysticercoid. Elephants become infected by eating forage harboring the mites and cysticercoid larvae. While tapeworms are generally thought to cause little pathology, heavy infections in young calves can be serious and can cause impactions (Warren et al., 1996). Praziquantel is the anthelmintic of choice.
Stomach bots (gastric myiasis)
Asian elephants are susceptible to infestations caused by Cobboldia elephantis. Adult flies lay eggs at the base of the tusk or tusk sulcus. Eggs are ingested and hatch in the stomach. In mild cases signs include loose stool, mouth breathing, and mud eating. Diarrhea, loss of appetite, colic, and anemia may be seen in severe cases (Mar, 2006). Heavy infestations have the possibility of causing gastric rupture. Ivermectin or trichlorfon are effective. Camphor oil or neem oil can be applied to the base of the tusks as a repellent (Mar, 2006). Some eggs may already hatch on the skin and the larvae may migrate to the tusk sulcus and cause a sulcus infection.
Blood parasites
Trypanosomiasis (Surra, Thut). Trypanosomiasis is a protozoan disease transmitted by biting flies and mosquitoes. It is most prevalent in Asia during the rainy season. Clinical signs may include fever, extreme weakness, lethargy, dry skin, anemia, and a progressive loss of body condition leading to emaciation. Constipation or diarrhea may be present or feces may be normal. Edema of the face, trunk, neck, lower abdomen, and limbs may be seen (Desquesnes et al., 2013).
Characteristic organisms can be seen on blood smears collected during episodes of fever. An ELISA has also been developed and used for a serosurvey in Thailand (Camoin et al., 2018). Cases have been reported in Myanmar, Thailand, and India. However, Surra does not seem to be common in Sri Lanka and may be most likely to occur when elephants are in close proximity to infected cattle or buffalo. Diminazene aceturate is recommended for treatment, however the dosage is controversial. Three elephants in Thailand treated with 5 mg/kg relapsed (Desquesnes et al., 2013). A single elephant was successfully treated increasing the dosage to 7-8 mg/kg (Rodtian et al., 2012) but the drug is known to have serious side effects so should be used with caution.
Babesia (Babesiosis, Piroplasmosis, Tick Fever). Babesiosis is a tick-transmitted protozoan disease. It has rarely been reported in Asian elephants (McGaughey, 1961) and even in African elephants there are only a few publications (Brocklesby and Campbell, 1963; King'ori et al., 2019). Clinical signs may include weakness, fever, jaundice, constipation, and hemoglobinuria. Characteristic organisms can be seen on blood smears. Three elephants diagnosed with babesiosis in Sri Lanka responded well to diminazine aceturate at a dosage of 3.5–7.0 mg/kg (personal communication Dr. Indira Silva, Sri Lanka, 2005).
Plate 8.1 Images of parasites. Click on image above to start slideshow.
Sepsis
Sepsis (also called septicemia) is a bacterial infection in the blood or tissues. Bacteria generally enter the body through broken skin or wounds. In newborn elephants, bacteria can enter via the umbilical cord and spread to various parts of the body. If the bacteria invade the joints a septic arthritis may result as shown in Figure 8.13.
Signs of sepsis can include fever, anorexia, and listlessness. Some calves will continue to eat. There may be lameness, pain, reluctance to stand, and swollen joints in the case of septic arthritis. The joints may feel warm. The white blood cell count will be elevated with an increase of rod-shaped heterophils. Blood cultures can identify the causative organism and appropriate antibiotics but due to the seriousness of this condition, a broad spectrum antibiotic or multiple antibiotics should be started immediately while waiting for results which may take 48 hours or more. Additional supportive treatment such as rectal fluid therapy and tube feeding may be needed. The prognosis is guarded.
Figure 8.14 Pus in the elbow joint of a calf that died of septic arthritis
Sunburn
Elephants, including calves can become sunburned if exposed to strong direct sunlight for long periods. Prevention is best by keeping the calf in a shady area during periods of intense sun. Sunburn is most likely to occur on the forehead and can be treated by flushing gently with cool water and applying soothing ointments (such as Himax, used in India).
Umbilical Cord Infection
At the time of birth, traction on the umbilical cord causes it to break separating the calf from the mother. Under normal circumstances, the arteries and veins retract and the umbilical stump dries up. Infections may occur if the cord becomes contaminated with bacteria during birth or shortly after.
Signs of local infection include swelling around the umbilical stump, purulent drainage (pus), and pain or heat upon palpation (touching) of the area. It is advisable to collect a sample of pus and submit it for bacterial culture and antibiotic sensitivity testing. Refer to the Medical Procedures chapter for how to properly collect a sample.
Systemic infection can occur if bacteria migrate up the umbilical stump and enter the blood stream.
In mild localized cases, clean the umbilical area, gently debride (remove dead or devitalized tissue) and flush the stump with dilute povidone iodine twice a day as needed. The attending veterinarian may elect to give systemic antibiotics based on culture results. The calf should be closely observed for any sign that the infection has become systemic (see sepsis in this chapter).
Umbilical Hernia
A hernia is the abnormal protrusion of an organ or tissue through the structures that normally contain it.
An umbilical hernia occurs when the umbilical cord does not separate easily causing the tissues around the opening to be stretched and preventing it from closing completely. The hernia appears as a bulge in the skin at the site where the cord was attached. The hernia may contain fat or a section of intestine or peritoneum (the thin tissue that covers the intestines). In some cases, a hernia may not be apparent until several weeks after birth.
Small hernias may not pose a problem and may close on their own but if the hernial ring is large there is the possibility that a loop of intestine could become trapped. This would compromise the blood flow leading to tissue death and the death of the calf.
There are only a few reports that discuss surgical repair of umbilical hernias in elephants. In one case repair was attempted on a 6-year female but failed due to post-operative infection (Pathak et al., 1990).
In another case, hernia repair was successful in a three-month-old calf that weighed 298 kg. Anesthesia was induced using xylazine, ketamine, and diazepam, and the calf was intubated and maintained using isoflurane, an inhalant anesthetic. Following resection of the hernial sac, the body wall was closed using absorbable sutures (#3 Vicryl®, Ethicon Inc., Somerville, New Jersey 08876-0151, USA) placed in a simple interrupted, pattern; the subcutaneous tissues were closed in two layers using a simple continuous pattern and #0 Maxon (Davis & Geck Monofil Inc., Manati 00701, Puerto Rico); subcuticular (instead of skin) sutures were placed using #0 Monocryl® (Ethicon Inc.). The authors give useful details regarding anesthesia and readers contemplating a hernia repair are advised to consult this reference (Abou-Madi et al., 2004).
The decision to perform surgery should not be taken lightly as there are risks to the procedure itself (which requires general anesthesia) and complications such as infection or wound dehiscence (breaking apart) may occur afterwards.
Ultrasound, if available, can be used to monitor the contents of the hernial sac and determine whether the hernial ring has closed on its own.
Surgery has the best chance of success if performed in a clean environment and before the elephant gains too much body weight (which puts pressure on the sutures). Post-operative management to keep the area clean is critical to prevent infection.
A non-surgical method hernia repair method was successful in two Asian elephant calves. The method involved manually reducing the hernia (pushing the contents of the sac back into the abdomen) and holding this position for 1–2 hours daily. The calves were first exercised by walking them two to four miles which made them sleepy and facilitated cooperation. The hernia resolved after five weeks in one calf and after five months in the other. This method requires a great deal of staff time and the mother, if present, must also tolerate the handling of her infant (Wiedner et al., 2008).
Wounds
Orphan elephant calves may present with a variety of wounds. Wounds may vary in severity from simple abrasions to life-threatening injuries. Wounds may be caused by snares, tigers, landmines, jaw bombs, or other causes. See sample images in Figures 8.15 a, b, 8.16, and 8.17 below.
A detailed presentation on wounds and wound treatment, along with additional images, is found here.
Click on image above to open PDF.
Figure 8.15 a and b. Shoulder and foot wounds from a tiger attack. The calf survived. Courtesy M. Razali, Malaysia
Figure 8.16 Mouth injury from jaw bomb in Sri Lanka. Photo credit: Vijitha Perera
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Figure 8.17 Trunk and foot injuries from a snare injury in Vietnam. Note that all the toe nails (and probably the distal toe bones) are missing. Photo credit: Willem Schaftenaar
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