The Status and Veterinary Problems in Captive Elephants in Sri Lanka

Ashoka Dangolla (BVSc., Dip. Vet. Epid., PhD)
and Indira Silva (BVSc, PhD)

Department of Veterinary Clinical Sciences
University of Peradeniya, Peradeniya 20400, Sri Lanka.



The majestic presence of the elephants makes the Sri Lankan pageants colourful and famous the world over. The elephants play a vital role in the tourist industry of Sri Lanka, which is a leading foreign currency earner. A majority of them had been captured from the jungles, at least 20 years ago, while some elephants are national or international gifts.

After the Land Reform Act of 1972, which limited the individual ownership of land to 50 acres (Jayawardene 1998), the number of owners dropped from 378 in 1970 to 140 in 1997. There was a demand for elephants for the timber market, and there also was a ready market from an increasingly affluent class of aspiring aristocrats, who viewed the ownership of an elephant as a status symbol. Subsequently, the domesticated, privately owned population of 532 in 1970 and 214 (in 1997) dropped to a present 180 to 190, to the best of our knowledge.

Non-invasive genotyping of DNA from epithelial cells in dung has shown to be reliable compared to blood extracted DNA (Fernando et al., 2003). Five polymorphic loci of tri- and tetranucleotide markers have been characterized in the elephants in Sri Lanka (Fernando et al 2001). This may become an important finding since blood samples can not be obtained from every elephant for genotyping. We have commenced a study on karyotyping of the Sri Lankan elephant. Presently we are seeking expertise in the possibility of using DNA or other molecular biological techniques on ivory of the Elephas maximus maximus.

The present estimate of domesticated elephants, in 15 of the 25 districts in Sri Lanka, is between 180 and 190. The largest number of domestic elephants belongs to the Temple of the Tooth (Maligawa) in Kandy in the central hills, followed by private owners; Millangoda (10), B.B. Jayasekera (7) and the Gangaramaya temple in Colombo (4) (Jayawardene 1998, and personal observations). The long felt need of the owners for an association was accomplished in November 1999 by forming, for the first time in Sri Lanka, The Captive Elephant Owners’ Association for the welfare of the captive elephant.

Very few elephant calves had been born so far to privately owned domesticated elephants in the country, though some females are at breedable age and regularly come into “estrus” (Wijesinghe et al., 2002). Most recorded births in domesticated elephants are from females that had been pregnant at the time of capture, and there is no incentive by the owners to breed their elephants. The female “Pooja”, born on 05 August 1986 is the first recorded birth from domesticated parents from the district of Kegalle; the mother, Lakshmi, owned by the late Sam Samarasinghe of Hiriwadunne had been 14 years old and the father, Kandula owned by Rambanda Kempitiya at Kivulpone, had been between 25-30 years of age. Carminie and Sandith Samarasinghe of the Millennium Elephant Foundation (MEF), maintains a shelter for the sick and old females at Hiriwadunne, own both Pooja and Lakshmi. Although Sri Lanka has >50 Non Governmental Organizations (NGO) dealing with elephants, only the MEF contributes towards the health care aspects of captive elephants by providing veterinary services, and housing for sick domestic elephants at their premises.

Ilangakoon (1993) observed that 29 of 180 elephants did not work at all; they belonged to religious institutions, Sri Lanka Army as a mascot, or upon the owner’s consent, or they were sick or too young to work. Some owners earn revenue from their elephants, while some allow the keeper to find work and earn the keep of the elephant. A few keep elephants for prestige or as pets because they like elephants or because their families have kept elephants for generations, and these elephants lead a relaxed life and are usually well cared for.

Owners find it increasingly difficult to maintain their elephants due to scarcity of food, unavailability of veterinary services in most areas, and shortage of work for an elephant due to mechanization of the timber industry. Although logging elephants work only 4-5 hours/day, those in the tourist trade work almost 30 days/month (Dangolla et al, 2002a). Generally, domesticated females are preferred for work because of their compliance. Most working elephants get access to food and water once they had bathed for about 2-3 hours after work.

Even though owners face many problems they prefer to own at least one more elephant (Jayawardene 1998), and therefore need advice and assistance to breed their elephants and training on new methods of elephant management. Owners and keepers need education on foot care and on balanced diet, since different foliage and soil in some parts of Sri Lanka are deficient in minerals such as calcium and magnesium (Dangolla et al, 2004a).

The domesticated elephants are almost always a part of colourful pageants held for religious and cultural events. When elephants are taken in processions extending for several days, they are forced, to sleep during the daytime as they get disturbed at night from distractive noises of the festival (Dangolla et al 2002b). Thus, most of them sleep in water during the day for about 2 hours and at night on their sides for a further 3-4 hours. Some elephants never sleep at night, when they are taken for such processions.


All keepers are Sinhala (Race), Buddhist (religion) males and half of them are >41 years old (Dangolla et al, 2002b). A majority (70%) earn more than an average labourer, and have studied up to Grade 8 (79%). They provide satisfactory level of education to their children, and none of them like their children to be elephant keepers. They carry a goad (ankus), a stick and a knife all the time. Almost all of them chew beetles (herbal leaves) and approximately 50% were regular alcohol consumers or heavy smokers. They prefer only native herbal medicaments for their elephants.
Although Sri Lanka is reported to have well over 50 Non Governmental Organizations (NGO) dealing with elephants, very few of them actively contribute towards the well being of the elephants at the field level. From a veterinarian’s point of view, at present, a majority of owners and elephant keepers have enormous faith on native ayurvedic medicaments for different ailments of their elephants.


Status of elephant medicine in Sri Lanka

The “Veterinary Science (Elephants)”-Vol.1 (Deraniyagala, 1952) records “…the National Museum of Ceylon has placed on permanent record, a national science, which had reached a high level of development under the Sinhala kings, although it is but little known today even among the elephant keepers (mahouts)”. Ancient sinhala palm leaf manuscripts describing the veterinary aspects of elephant management are preserved in the Museums in Colombo and Kandy. The relevant palm leaves are (Deraniyagala, 1952);

- The “Hasti Yoga Satakaya” and “Hasti Silpaya” (a Sanskrit work with a verbatim translation in to sinhala), describes the medicines, their preparations and the diseases they cure; remedies for eye diseases, gastric, bowel and bilious disorders, skin diseases, ointments, conditioning medicines and cautery; prescriptions for oils, ointments, pastes, powders, pills, etc.; sores and ulcers; a glossary of medical terms.
- The “Ath Veda Pota”, a Sanskrit work with a verbatim translation in to sinhala, describes medicines for adults as well as calves.
- ?thun Alinta Vedakam” and “Gaja Yoga Ratnaya” describes medicines administered to ensure affection and fidelity.
- “Ali Torana Pota” describes ophthalmic medicines.
- “Sri Yoga Sataka” describes diseases, their symptoms and treatment.
- “Hasti Cikitsava” describes various medicines, drugs, pills used in the treatment of elephants.


According to those palm leaves, the type of diseases and conditions that existed in elephants in ancient Sri Lanka include, skin and foot conditions (wounds, ulcers, abscesses), wounds on genital organs, “worm eating” of tusks, worms in ulcers, eczema, gun shot wounds, eye diseases, gastric, bowel and bilious disorders.
 
In ancient Sri Lanka, it has been customary for physicians for elephants, horses as well as humans, to accompany the king and his convoy to war. In chapter XXXVII of the Mahavansa (The Great Chronicle of Sri Lanka) (Wijesinghe and Mudaliar, 1889), describes how King Buddhadasa (882 Buddha Era, 338 AD) had “… appointed medical practitioners to attend to his elephants, his horses and his army” (Chapter 37). King Rajasinghe I (1581-1593 AD) had maintained 2000 elephants in his royal stables (Jayawardene, 1998). There are at least two records on the treatment of elephants in the Mahāvamsa (Wijesinghe, 1889).

1. The great victory of King Duttagāmini (Chapter 25) describes how the war elephant of the king, “Kandula”, also known as “Kadol Etha”, broke down the high wall around the Vijithapura. “… The tusk-elephant, placing himself on his knees and battering a stone wall ….. made his way to the iron gate. The Damilas (the opponents) who defended the gate hurled upon him every kind of weapon, heated balls of iron and molten lead… The agonized Kandula rushing to water, submerged therein. The elephant physician then washed away the pitch and applied medicine. The king ….stroking its forehead with his hand, (spoke kind words to him). Having cheered it on and got it fed with excellent fodder, he had it wrapped with a shawl and well clad in armour. Having formed a seven-fold, well softened buffalo hide, he adjusted it on the elephant’s back, and spread an oil-soaked hide over it, he sent him forth.” The analgesic effect of the medicine the physician had applied can be estimated by the description of how Kandula continued to fight the war bringing victory to the king who then became the Great King Duttagāmini (382-406 Buddha Era, 101-77 B.C.). “…Kandula, roaring like thunder and daring danger, crashed the gates to the ground.”

In ancient Sri Lanka, it has been customary for physicians for elephants, horses as well as humans, to accompany the king and his convoy to war. In chapter XXXVII of the Mahavansa (The Great Chronicle of Sri Lanka) (Wijesinghe and Mudaliar, 1889), describes how King Buddhadasa (882 Buddha Era, 338 AD) had “… appointed medical practitioners to attend to his elephants, his horses and his army” (Chapter 37). King Rajasinghe I (1581-1593 AD) had maintained 2000 elephants in his royal stables (Jayawardene, 1998). There are at least two records on the treatment of elephants in the Mahāvamsa (Wijesinghe, 1889).

1. The great victory of King Duttagāmini (Chapter 25) describes how the war elephant of the king, “Kandula”, also known as “Kadol Etha”, broke down the high wall around the Vijithapura. “… The tusk-elephant, placing himself on his knees and battering a stone wall ….. made his way to the iron gate. The Damilas (the opponents) who defended the gate hurled upon him every kind of weapon, heated balls of iron and molten lead… The agonized Kandula rushing to water, submerged therein. The elephant physician then washed away the pitch and applied medicine. The king ….stroking its forehead with his hand, (spoke kind words to him). Having cheered it on and got it fed with excellent fodder, he had it wrapped with a shawl and well clad in armour. Having formed a seven-fold, well softened buffalo hide, he adjusted it on the elephant’s back, and spread an oil-soaked hide over it, he sent him forth.” The analgesic effect of the medicine the physician had applied can be estimated by the description of how Kandula continued to fight the war bringing victory to the king who then became the Great King Duttagāmini (382-406 Buddha Era, 101-77 B.C.). “…Kandula, roaring like thunder and daring danger, crashed the gates to the ground.”

In ancient Sri Lanka, it has been customary for physicians for elephants, horses as well as humans, to accompany the king and his convoy to war. In chapter XXXVII of the Mahavansa (The Great Chronicle of Sri Lanka) (Wijesinghe and Mudaliar, 1889), describes how King Buddhadasa (882 Buddha Era, 338 AD) had “… appointed medical practitioners to attend to his elephants, his horses and his army” (Chapter 37). King Rajasinghe I (1581-1593 AD) had maintained 2000 elephants in his royal stables (Jayawardene, 1998). There are at least two records on the treatment of elephants in the Mahāvamsa (Wijesinghe, 1889).

1. The great victory of King Duttagāmini (Chapter 25) describes how the war elephant of the king, “Kandula”, also known as “Kadol Etha”, broke down the high wall around the Vijithapura. “… The tusk-elephant, placing himself on his knees and battering a stone wall ….. made his way to the iron gate. The Damilas (the opponents) who defended the gate hurled upon him every kind of weapon, heated balls of iron and molten lead… The agonized Kandula rushing to water, submerged therein. The elephant physician then washed away the pitch and applied medicine. The king ….stroking its forehead with his hand, (spoke kind words to him). Having cheered it on and got it fed with excellent fodder, he had it wrapped with a shawl and well clad in armour. Having formed a seven-fold, well softened buffalo hide, he adjusted it on the elephant’s back, and spread an oil-soaked hide over it, he sent him forth.” The analgesic effect of the medicine the physician had applied can be estimated by the description of how Kandula continued to fight the war bringing victory to the king who then became the Great King Duttagāmini (382-406 Buddha Era, 101-77 B.C.). “…Kandula, roaring like thunder and daring danger, crashed the gates to the ground.”

2. The other record is on how the Great King Duttagāmini had covered the soles of the elephants, used to stamp down large stones for construction of the Mahāthūpa (big stupa), with leather to prevent from injury (Chapter 29). The method of preparation of such leather soles would be valuable when treating pododermatitis in present day captive elephants.
Western therapy for elephants evolved later and based on our experience, the use of native medicines is beneficial in enhancing the prognosis of western therapy. The herbal mixtures for removal of pyogenic membranes in abscesses, and treatment for constipation are two examples.

Sri Lankan domesticated elephants originate mainly from the wild population. Permits to capture wild elephants however, have not been issued for at least 20 years. This is the main reason why we do not see much young elephants in our domesticated population. Therefore, the care taken in protecting wild elephant become equally or even more important. Examining the strengths and weaknesses of the legal involvements by wildlife workers is of importance in this exercise. Probing in to court cases conducted by the Department of Wildlife Conservation during 2001 revealed that many culprits are not punished adequately and evidence are not handled in a professional manner (Bandara et al., 2004). The laws and regulations are relatively loose and poachers escape with minor fines and repeat poaching. Poor record keeping and poor knowledge of officials regarding the legal aspects were the other reasons for this unfortunate situation.

The presence of the Tapetum lucidum in the choroid layer of the eye of asian elephants was documented in the Sri Lankan elephant recently (Dangolla et al., 2005a). The Tapetum lucidum enhance vision, particularly night vision, by reflecting light rays several times on the retina.

Elephants function visually by both day and night. An “alternate vision” has been described in African elephant whereby they view the horizon on one side monocularly, and the front of and below the head binocularly. The binocular vision includes the visual field in which the trunk is most commonly active, which support the common belief by villagers that the visual field of elephants is confined to the area covered by movement of the trunk.

The right eye of a 45 year old domesticated male elephant collected at post mortem was revealed the following data. The globe of the eye measured 70 mm MLD, 60 mm APD and 55 mm SID. The cornea was 3 cm in diameter and slightly opaque. The optic nerve was 3 cm in length. The cut section showed semi-solid white vitreous. Two out of the three tunics were clearly visible in paraffin sections of 5-6µ stained with Haematoxylin and Eosin, namely, the fibrous outer tunic and the vascular inner tunic. The collagen fibres of the sclera with melanocytes were arranged parallel to the surface of the globe. Two distinct layers were seen in the highly vascular choroid. The suprachoroid layer consisting of collagen bundles with fibrocytes and melanocytes, and the outer highly vascularised layer were identified. The retinal pigment epithelium appeared as cuboidal with a basal laminar. A highly fibrous layer with a few fibrocytes present between the vascular layer of the choroids and the retinal pigmented epithelium corresponds to the tapetum lucidum as described in the African elephant. The fundus of African elephants has a distinct tapetum which is bluish in colour and conical in shape and the border of the tapetum runs closer to the temporal margin of the fundus than to the nasal margin. Further observations are warranted to study the histology of the other parts of the eye.


Sedation/Anaesthesia

“Immobilon” has always been used whenever tranquilization is needed (Dangolla et al., 2004b), except in very few instances in which Xylazine used instead. We have compared the effects of Xylazine IV and IM injections especially in smaller quantities, Detomidine hydrochloride and Acepromazine hydrochloride and their combinations as sedatives for minor surgical interventions in elephants. It is believed that Xylazine is still the best, 40-80 mg given intravenous on the laterally recumbent animal. This is specially so, as we have more experience with this drug and also an antidote is available (Kumudini et al., 2004). At times, Xylazine was out of the market for several months and alternative drugs therefore need to be sorted with the awareness of their possible unwanted effects such as causing hypotension.

Wild elephants need to be captured for domestication which would require properly calculated doses of anaesthetic injected using a projectile syringe. Though several workers have worked on formulas to calculate the bodyweight of elephants using height, fore feet circumference and length of elephants, none of these measurements can be easily taken in the wild, and therefore the dose is always a guess. An inexpensive equipment was therefore produced to measure the height of the elephants from a distance (Dissanayake et al., 2003). This equipment can be handled by one person and only weigh 4.5 kg, which can therefore be taken into jungles without difficulty. Two light rays and two cross hairs are aligned to the highest and the lowest position of the elephant in order to calculate the height. The calculation appears to be approximately 70% accurate. The weight of the elephant is then estimated by the height-weight conversion (1 foot=500 pounds). Such information would be extremely important for wildlife and zoo veterinarians who would be requested to anaesthetise elephants for various reasons (Dangolla et al., 2004b).


Common Diseases and Conditions

Since most of the elephant population in Sri Lanka are relatively old, and are on their last (6th) pair of molars, they develop signs of the mal absorption syndrome (Dangolla and Silva, 2002). The clinical signs are mainly due to defective chewing of the ordinary roughage diet. Six pairs of premolar-molar fused jaw teeth erupt in elephants, during their life time. When elephants are about 45 years, they carry their last pair of jaw teeth. Their direction of teething is oblique and not straight as observed in most other domesticated animals. Thus, teeth are not suitable to carry heavy weights (logs) or not suitable to bite on hard food material. Absence of enamel on surface, make their teeth more fragile.

When signs are noticed by experienced elephant owners, they work the elephants in “SAFARI”s to carry tourists which does not involve working by mouth. Veterinary intervention is required however, when the clinical condition deteriorates. When these signs are noticed, generally owners and keepers make sure that the elephants in questions sleep adequately especially when taken for processions (Dangolla et al., 2002b).

Sand cracks (nail cracks), leading to sole cracks and to pododermatitis (foot rot) is common in captive Sri Lankan elephants (Gamage et al., 1999). The privately owned elephants walk for long distances on rough surfaces such as tarred roads or sand especially during the festival seasons, and stand on dirty stables throughout the entire night and may not get nutritionally correct diets. In rainy weather the foot rot gets aggravated and owners and keepers are advised to attend to the drainage of the stable which is very important during the rainy seasons. Foot rot could even be life-threatening, if not attended properly and on time. Many owners still have faith on native medicine for this condition.
When food is given after a long period of starvation, elephants eat faster without properly chewing. This results in constipation and impaction of food mainly in the colon resulting in constipation. When food with long fibres, such as un-chopped banana trunks is eaten, the elephants develop impaction and/or constipation faster. Bad teeth in old age add gravity into impaction/constipation. Most affected animals appear depressed, weak, dehydrated at times, strain to different degrees and there could be signs of colic. Appetite could vary depending on the degree of severity (most elephants don’t open their mouth when they are ill !). Among the native medicines, fumigation of medicaments under the belly of the elephant is practiced.

The vision of approximately a third of domesticated elephants has been shown to be seriously impeded by corneal opacity and cataract, particularly in old age. Involvement of protozoan parasite namely, Acanthamoeba and Toxoplasma gondii with corneal ulcers was documented by us (Dangolla et al., 2005b and Dangolla et al., 2004b). Clinically, it has been felt that Acanthamoeba appears during the drought period and dissapears in the rainy season. However, an investigation to examine the presence of this organism in the eyes of normal elephants over a period of a year is underway. Fourteen (14) of 45(31%) elephants tested were sero-positive for Toxoplasma gondii antigen. Though none of the sampled animals showed any clinical sign, the presence as titres above 1:200 may suggest active infection or reactivation due to immuno-suppression as evidenced in humans and other animals. The significance of T. gondii sero-positivity to clinical diseases in elephant is unknown.

It has been felt that filariasis, play some role in eye conditions, though it has not been proven. Stephenofilaria adult worm causes haemorrhagic dermatitis and the microfilaria in domesticated elephants in Sri Lanka, becomes numerous in blood after 12.00 midnight until about 5-6.00 am. During the day time, micro filarial counts may be relatively low.
Surgical removal of an affected lens of an elephant was successful though the post operative care was a problem (Kuruwita et al., 1991). The elephant did not keep the dressing in place after surgery. It is also noteworthy mentioning that the elephant owners believe, when the eye conditions get better, elephants develop some foot condition and therefore, tend to pay less attention to the eye.

Arthritis and/or arthrosis are very common among old domesticated elephants and most of them are due to goad injuries caused by keepers. Young animals tolerate traumatic injuries without much difficulty but when they grow older, the problems re-appear. Man inflicted wounds/abscesses and sinuses are common in elephants. The skin of wounds, heal faster in elephants leading to subsequent abscess formation. The musth gland of some males get inflamed, infected and/or ducts get blocked. The infected glands need surgical interventions.

Diarrhoea is seen especially in calves, most commonly in artificially fed calves due to imbalances in food. At times, it is caused due to defective digestion and absorption in calves. Changes in milk and diet are equally important especially in claves. Only salmonellosis is the confirmed infective cause in Sri Lanka. Elephant in musth develop diarrhoea when very young Caryota urens (Kitul) stems are fed. Balandtidium coli are commonly found in domesticated elephants with diarrhoea which responds well for sulfa-trimethoprim combination given paranteral or oral.

One case of rabies in a domesticated elephant was reported and confirmed (Wimalaratne and Kodikara 1999). Heat stroke was suspected in one male elephant, after being in hot sun without food and water for 5 consecutive days and died. The trunk had been flaccid and short. Tetanus also has been reported to produce a stiff trunk and nervous signs.
It has been shown that the levels of lead (Pb) and copper in blood of domesticated elephants are much higher compared wild (free ranging) elephants in Sri Lanka. This indicates that feed given to domesticated elephants, mainly originating from urban area, are contaminated with vehicle exhaust. Since most elephants walk through cities and are fed essentially foliage from the area, Pb poisoning need to be anticipated in future (Jayasekera and Kuruwita, 1996). Since most effects of lead are on the reproductive system, and since Sri Lankan domesticated elephants are not commonly used for breeding, the effects can be masked for several years.

Intra-erythrocytic bodies similar to Babesia were observed in three relatively old elephants showing signs of weakness, lethargy and anaemia. All of them responded well for intramuscular injection of “Berenil” (Diminazine aceturate) with haematinics.
Among the helminths, Murshidia spp. Quilonia spp., Parabronema spp., Gramocephalus spp. Choniangium spp., Bathmostomum spp., Coboldia, Schistosomes and Fasciola spp. (Rajapakse et al., 1999, Alahakoon, 1994, Kuruwita and Vasanthatilake, 1993, Seneviratne and Jayasinghe, 1968, Seneviratne, 1955) has been reported from elephants in Sri Lanka.

An elephant with a chronic skin problem stimulated investigations on serum thyroid levels in domesticated elephants. Our observations suggest that the thermoregulatory behaviour of Elephas maximux maximus has similarities to that of the buffalo, where the skin plays an important role (Kumudini et al 2005). There is additional evidence that substantial amount of water is lost through cutaneous evaporation, though it is generally believed that the elephants have no or little sweat glands on skin compared to other species (Bandara et al., 2005).

The first live elephant in which Mycobacterium Tuberculosis infection was confirmed and treatment administered was reported recently (Dangolla et al., 2002c). When this condition was difficult to diagnose, for further treatments, the elephant was walked over a long distance. The clinical condition precipitated subsequently and the elephant could not get up. During the forceful assisted hoisting, the elephant expelled some phlegm from trunk which was submitted to a laboratory. Both direct smears and culture reports revealed the presence of M. tuberculosis. Treatments were administered with Isoniazid, Rifampicin and Piricinamide with Salbutamol, initially orally and subsequently per rectally except Salbutamol. Animal succumbed to the condition at the end of the third day after treatment was initiated and a minimal post-mortem performed. The lung tissue submitted to the laboratory for pathology further confirmed the condition (Dangolla et al., 2002c). A trunk wash procedure for bacteria culturing is on going at the moment, to screen our domesticated elephant population for this devastating zoonotic disease. It is also to be mentioned that most of the domesticated elephants in Sri Lanka do not allow touching the trunk and therefore, the trunk wash procedure does not work properly. An alternative testing procedure on blood needs to be established for this purpose.
(Some information written on diseases and conditions has been accepted for publication in “Biology, Medicine, & Surgery of Elephants”, edited by ME Fowler and S Mikota, and published by Blackwell Publishing, USA.)


References

Alahakoon J. (1994). Presence of liver fluke Fasciola jacksoni in a Sri Lankan elephant. GAJAH (12):46-47.
Bandara KAPA, Dangolla A and AAJ Rajaratna (2005) Water balance in Asian elephants (Elephas maximus maximus). 57th Annual Convention and Scientific Sessions of the Sri Lanka Veterinary Association, 23-24th May 2005, 21pp.
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