Chapter 5 Health as an Indicator of Well-Being in Captive Elephants Gretchen Kaufman and Janet Martin Cummings School of Veterinary Medicine Tufts University Elephants are wild animals. They have evolved over millennia to survive in the savannas and forests of Africa and Asia. They have developed physiological systems designed to meet conditions defined by these environments. Their evolution has resulted in specific adaptations to local constraints affecting nutrition from available vegetation, distribution and availability of water sources, substrate, climate, predation and presence of disease-causing organisms. In addition, as intelligent animals, they have developed complex and varied social systems that are inextricably linked to their health and success as individuals. In contrast to their wild counterparts, elephants in zoos, circuses and sanctuaries are put in situations where they are required to adapt quickly to unnatural conditions. Taken out of their native environment, these animals are challenged by physiological and psychological factors that sometimes test the limits of their ability to cope and maintain a healthy state. The imbalance created by these factors may result in ill health or disease, and is not only a reflection of physiological stress, but also results in further suffering through the disease process itself. Elephant welfare is the responsibility not only of the elephants’ human caretakers but also of the society that has decided to keep elephants in their midst. Preventing disease and managing health problems humanely in our captive elephants is part of that responsibility. It is the premise of this chapter that, although good welfare may not guarantee good health, ill health and chronic disease indicate a lack of well-being and produce a state of diminished welfare. We postulate that objective measures of health and disease can be used as one of several indicators of well-being, and therefore recommend that routine monitoring of certain health parameters should be considered as one of the important tools used to assess general well-being and guide management decisions within captive elephant collections. What is disease and how does it relate to welfare? Disease can be defined as “any impairment that interferes with or modifies the performance of normal functions, including responses to environmental factors such as nutrition, toxicants, climate, infectious agents, inherent or congenital defects or combinations of these factors” (Wobeser 2006). Others have made a direct association between disease and suffering (Gregory 2004; Broom 2006). Disease states involve pathology, such as inflammation and destruction of tissues, which produce many physiological responses that result in well-recognized signs of suffering, such as pain, distress and depression, weakness, abnormal behavior, loss of appetite or starvation (Gregory 2004). If the disease is short-lived, consequences may be minimal. However, if the disease is chronic or 69

Chapter 5 - Health as an Indicator of Well-Being in Captive Elephants

repeated, it may result in permanent physiological outcomes such as structural defects, scars, arthritis, immune dysfunction or weakness that lead to further ill health and continued poor welfare. Health and disease represent a complex dynamic that is in constant flux. In most cases, disease-causing organisms such as parasites, bacteria and viruses are part of the normal ecology of an animal. Naturally occurring agents have evolved alongside or within the same environment as the host animal that has in turn evolved compensatory mechanisms to combat or control disease. The development of these compensatory mechanisms is called “adaptation” (Broom 2006). Some examples of compensatory or adaptive mechanisms are an effective immune system, detoxifying enzyme systems or behavioral adaptations that lead to avoidance of disease, trauma or predation. Adaptation occurs through a highly complex dynamic system that is governed by a myriad of internal and external factors. Internal or individual factors that may be important in the host include age, immune status, physical compromises secondary to trauma, physiological pressures (e.g., reproduction, growth, migration) and the nutritional status of that individual. Examples of important external factors would include social structure, and environmental factors such as climate, availability of water and food, and predation or introduction of novel agents. An animal’s ability or inability to adapt to changing internal and external challenges has direct consequences for well-being. In most cases, fluctuations or disturbances in internal and external factors are only temporary and will be compensated for through adaptive mechanisms designed to resolve imbalance. However, a disease state may persist or be so overwhelming as to overcome these adaptive mechanisms and result in compromise (i.e. illness or impairment), or even death. Very unusual circumstances, such as the extreme external challenges encountered in captivity, can push an animal past the threshold of its normal adaptive mechanisms, leading to a greater predisposition for disease and loss of well-being. One of the most significant responses to an internal and/or external imbalance that contributes to poor welfare is stress. Stress is a normal adaptive function and has some beneficial effects in the short term. However, chronic psychological or physiological stress, as may be experienced in association with chronic ill health, is detrimental, may result in immunosuppression and contributes to further disease (Gregory 2004; Broom 2006). As we discuss below and in the next chapter, many of the diseases of captive elephants are unique to their captive state and are likely to result, in part, from some level of chronic stress. What does it mean to be in captivity and how are humans involved? Elephants are influenced by human activities in multiple ways. In the optimal situation, wild animals living in the landscape in which they have evolved should be generally healthy and reproducing well (Lee & Moss, Chapter 2). Some would argue that no place on earth is free from human effects. One of the more extreme forms of human influences on elephants has been through the practice of capturing and maintaining them in captive settings. Elephants lend themselves to training and have been utilized by humans for thousands of years for work, worship and entertainment. However, any elephant living in captivity is still a wild animal. Because elephant reproduction in captivity has been so challenging, most captive elephants are only one or two generations removed from the wild and therefore have not undergone the selective breeding over multiple generations needed to successfully produce a domesticated animal (Sukumar 2003; Fowler & Mikota 2006). Thus, a trained elephant cannot be considered a domesticated elephant, and elephants in the captive context can be expected to be extraordinarily challenged both behaviorally and physiologically. As discussed above, animals placed in such conditions may reach the limits of their ability to 70

Gretchen Kaufman & Janet Martin

adapt to these abnormal conditions and be prone to developing diseases or comprised health and therefore experience diminished welfare. Human society has a responsibility to minimize the negative impacts of keeping elephants in captivity, including the effective prevention and treatment of disease. This is especially compelling for diseases or conditions that develop in response to the captive environment. Elephant caretakers and veterinary professionals have the tools to investigate, treat, monitor and develop prevention strategies for minimizing diseases of captive elephants, contributing to our responsibility for their overall well-being. How can health assessments be used to monitor well-being? The presence or absence of disease in captive elephants can be both measured objectively and assessed quantitatively, making the evaluation of health status an especially useful tool in assessing the well-being of captive animals. Captive elephants in North America frequently exhibit a number of illnesses that are either not experienced at all by their wild counterparts, or not experienced at the same frequency. These diseases therefore create a lack of well-being in elephants that is a direct consequence of captivity. Many of these diseases are chronic in nature, and even though occasional illness due to accident or disease can be experienced by any animal, chronic disease states can certainly be equated to a lack of well-being. As veterinarians we are trained to focus on disease specifics: etiology, pathology and treatment options. Zoo veterinarians and others caring for captive elephants have developed many creative methods for assessing and treating our gargantuan patients, and great strides have been made in recent years in improving diagnostic modalities and medical treatments for elephants. While we are often charged with diagnosing and treating a sick elephant patient, frequently a more holistic investigation of the factors precipitating the particular disease state is not encouraged. Clearly defining and addressing the underlying factors contributing to the disease state are crucial to adequately improving the long-term well-being of these animals. Among these conditions are several infectious diseases, multiple husbandry-related conditions, nutritional diseases and reproductive dysfunction that all contribute to diminished welfare in the captive elephant. These impede elephants’ ability to effectively respond to new health challenges, thereby perpetuating further lack of well-being. How is captivity related to specific disease states? In captive elephant populations infectious diseases such as tuberculosis (Mikota, Chapter 6) and endotheliotropic elephant herpes virus (EEHV) infection can be directly related to transmission of organisms from one species to another unrelated species. Infection is directly related to the exposure of captive elephants to species with which they would not normally have direct contact in the wild. In the case of tuberculosis, the close proximity of captive elephants to humans creates an opportunity for exposure to the human M. tuberculosis organism that would be unlikely to occur in a wild elephant population. The many deaths of young captive elephants due to EEHV infection are thought to be related to the practice of mixing African and Asian elephants. This exposes Asian elephants to an organism that is carried relatively benignly by African elephants, but is fatal to Asian elephants (Fowler & Mikota 2006). Husbandry-related diseases such as foot problems, oral health problems and skin disease also have unique characteristics related to the captive setting. Pathological conditions of the elephant 71

Chapter 5 - Health as an Indicator of Well-Being in Captive Elephants

foot due to lack of mobility from inadequate space, development of stereotypic behaviors and inappropriate substrate are unique to captivity and frequently lead to euthanasia of captive elephants in North America. Dental problems seen in captivity can be precipitated by lack of appropriate browse material and inappropriate diets (see below; Fowler & Mikota 2006). Captivity in northern climates where indoor housing in heated barns is necessary for long periods of time creates the opportunity for pathological skin conditions not seen in the wild, as well as multiple other abnormal health conditions. Nutritional diseases are frequently encountered in captive elephants and range from inappropriately formulated diets to sand impaction colic. Hand raising infant elephants without complete knowledge of their nutritional requirements often results in young animals that fail to thrive (but see Sheldrick, Chapter 16; Fowler & Mikota 2006). Successful reproduction is often used as a measure of well-being in captive animals. Unfortunately, in captive elephant populations in North America, reproductive problems have been the norm rather than the exception. Due to the difficulties involved in providing opportunities for natural breeding, elephant reproduction is often only possible using artificial manipulation of the cow and bull. However, few institutions have the capacity to collect semen and many captive elephant cows have shown a variety of problems with cycling and lack the ability to conceive. Even if pregnancy is achieved, difficulties encountered during gestation and birth frequently result in loss of the calf. Raising calves to successful adulthood in which they are not only physically healthy but also retain the behavioral repertoire to function in a herd setting has also proven to be difficult in captivity. There are many challenges to the medical management of elephants in captivity. Captive settings for elephants range from zoos, circuses and sanctuaries, to working forestry elephants. The quality or quantity of veterinary care available in these settings varies widely but is not the sole determinant of animal health. An elephant at a spectacular and well-funded zoo facility with access to top-quality medical care may still experience a more compromised state of well-being overall than the forestry elephant. The captive setting as a whole will be directly reflected in the health and well-being of the elephant in that setting. There are excellent resources available to guide monitoring of captive elephant health, especially the Guidelines for Comprehensive Elephant Health Monitoring Program (American Zoo and Aquarium Association 2005). This type of resource provides a framework for the routine and careful monitoring of specific health parameters. These data need to be utilized in an ongoing strategy for assessment and improvement of well-being in a collection. It is important to build creative communication forums and networks that promote the value of sharing information and conducting cooperative research endeavors, leading to the improved health and well-being of captive elephants.  Thorough health monitoring is only the first step in assessing the well-being of a captive elephant. The information gathered must then be analyzed and any factors underlying the health issues must be carefully evaluated. A commitment to addressing these underlying factors, however difficult that may prove to be, must be present at all levels in order for us to fully accept the responsibility for improving the health and well-being of the captive elephants in our care today—and in the future.

72

Gretchen Kaufman & Janet Martin

References

American Zoo and Aquarium Association. 2005. Guidelines for comprehensive elephant health monitoring program. Elephant Species Survival Plan, http://www.elephantcare.org/protodoc_files/2005/Eleph% 20SSP%20Routine%20Health%20May%202005.pdf Broom DM. 2006. Adaptation. Berl Munch Tierarztl Wochenschr. 119(1-2):1-6. Fowler ME, Mikota SK. 2006. Biology, medicine and surgery of elephants. Ames, IA: Blackwell Publishing. Gregory NG. 2004. Physiology and behaviour of animal suffering. Ames, IA: Blackwell Publishing. Sukumar R. 2003. The living elephants: evolutionary ecology, behavior, and conservation. New York, NY: Oxford University Press. Wobeser GA. 2006. Essentials of disease in wild animals. Ames, IA: Blackwell Publishing.

Gretchen Kaufman is an Assistant Professor of Veterinary Medicine in the Department of Environmental and Population Health and Director of the Tufts Center for Conservation Medicine. She graduated from Tufts University School of Veterinary Medicine and completed a residency in zoological medicine at the University of California, Davis. She went back to Tufts to create and run the Exotic Animal Medicine Service in the small animal teaching hospital. After six years she returned to the Tufts Wildlife Clinic where she has continued clinical teaching, clinical and international research and didactic teaching in zoo, wildlife and exotic companion animal medicine. Dr. Kaufman focuses on wildlife medicine curriculum development in the veterinary program, spearheading graduate programs in conservation medicine and coordinating environmental education at the Tufts Institute for the Environment. She conducts veterinary medical research and service projects in Nepal, primarily on rabies prevention/ control and the dynamics of tuberculosis among humans, domestic animals and wildlife (including elephants). Dr. Kaufman also chairs the “Greening the Grafton Campus” Committee, working with other members of the campus community to reduce the environmental footprint of all aspects of the veterinary school’s activities. She may be reached at Cummings School of Veterinary Medicine, Tufts University, 200 Westboro Road, North Grafton, MA 01536 or [email protected]. Janet Martin obtained her DVM degree from the Tufts University School of Veterinary Medicine in 1990. After completing two internships, one in Small Animal Surgery and one in Wildlife and Zoo Medicine, she joined the staff of Roger Williams Park Zoo as the Associate Veterinarian. In 1997 after a six-month sabbatical at the Royal Melbourne Zoo in Australia, she returned to Roger Williams Park Zoo as the Director of Veterinary Services. Dr. Martin acts as the veterinary advisor to both the Monotreme and Marsupial Taxon Advisory Group of the American Association of Zoos and Aquariums, and the Tree Kangaroo Conservation Project, and in 1999 and 2003 accompanied the TKCP field research team to Papua New Guinea. Dr. Martin is currently a Research Assistant Professor at Tufts University Cummings School of Veterinary Medicine working on infectious disease in wildlife. She may be contacted at Cummings School of Veterinary Medicine, Tufts University, 200 Westboro Road, North Grafton, MA 01536 or [email protected].

73