The Rhino with Glue-On Shoes Page 5

  But here too there were challenges to consider. Kayavak had never actually been in the same habitat with Puiji. The two might not bond. The adult whale could be aggressive or uninterested. She might not produce any milk. How much time could we give these two to forge a relationship before we’d feel compelled to intervene and feed Kayavak? And could we determine if the calf’s nutritional needs were being met, when and if nursing began? Ultimately, this option left a lot to chance. We had to decide how comfortable we were with the idea of letting go. The calf’s fate would be largely out of our control in this scenario.

  Another pool drop just after midnight to give the calf a second dose of fluids left staff tired. Kayavak, on the other hand, acted as if the night had just begun. She looked for attention and repeatedly swam over to the trainers stationed poolside. Clearly, she wanted them in the water with her.

  We took her cue and started a new rotation: swimming with Kayavak. Trainers lined up for this assignment. It hardly felt like work. They swam alongside the curious whale or floated on rafts within reach, allowing her to brush their hands as she passed nearby. If Kayavak was grieving, she was also pragmatic. She learned very quickly where she could get the attention she wanted. These wet-suited people might not be great swimmers, but they were acceptable as new companions.

  I often marvel at how much we know about these animals, yet how much more we need to learn. Although you won’t find the definitive textbook on rearing orphaned beluga calves on your library shelf, you will find, among the ranks of veterinarians the world over, a willingness to innovate, to extrapolate, and to share experiences. We tapped into the aquarium world network again to explore our third option for Kayavak: weaning her straight onto fish.

  No one had tried this approach in a whale calf. But we heard several encouraging stories about dolphins. Young dolphins will start eating whole fish even while continuing to nurse. We heard about one dolphin successfully weaned from nursing at six months of age. Although the information trickling in from our colleagues did not exactly amount to a peer-reviewed scientific paper, it did represent the most intriguing and, in many ways, the least risky of our three choices. Conventional wisdom was that a six-month-old whale needs milk. But if a six-month-old dolphin could survive on fish, why couldn’t a whale calf? Plus, we were sure we could train Kayavak to eat.

  We met to share our ideas. Veterinarians, curators, and trainers pooled their thoughts and expertise while the aquarium’s director looked on. We called more experts, combed the literature, and borrowed a page or two from domestic animal medicine. There was no clear right answer. The only wrong answer was inaction, and so we moved quickly.

  By the first light of morning, we had our decision. We would abruptly wean Kayavak onto solid food. With this approach, we’d have control over her nutrition and intake; we could weigh her routinely, monitor her for illness, and still have the option of providing fluids and milk by tube-feeding if necessary. We’d blend aggressive veterinary medicine, expert animal care, and intensive animal training. We’d teach Kayavak how to eat and then wean her from us—sooner rather than later.

  Kayavak ate her first fish on December 27.At that session, she received three herring. Though she gave us a quizzical look, she seemed no worse for the experience. By day’s end, she’d received two and a half kilograms of fish, or about 20 percent of what we’d calculated she would need each day. We continued to supplement her with fluids and treat her with antibiotics. The next day she was up to three and a half kilos. By week’s end, she was approaching trainers for food as well as attention. After three weeks, she was eagerly taking fish from the trainers.

  As expected, the whale lost weight at first, but she remained bright-eyed, energetic, and responsive to her human caretakers. She handled her new diet well, and her appetite was growing. After two months, the calf had surpassed her original weight. She was ready to meet the other whales.

  Before Immi’s death, Kayavak and her mother had lived together in a pool separate from the other belugas. They had access to each other only across netted gates. We wanted to minimize the chance of complications during birth and limit the risk of aggression toward the newborn. Mother belugas tend to be very protective of their babies. Additionally, female whales will sometimes try to steal another mother’s calf. Now we followed a step-by-step plan to introduce Kayavak slowly to the adults, one at a time, over a period of months. Each time we opened the gate that connected her pool to the adult pool and began an introduction to a new whale, we felt considerable trepidation.

  Immi had been the dominant animal in the pod before the birth of this calf. Whale social behavior depends largely on hierarchy; we wondered if Kayavak would benefit from her mother’s prior status. Such social dynamics are complicated, however, and what we understood about the rankings of our beluga community was likely just the tip of the iceberg. With Immi gone, things could have shifted in ways that would be hard to predict.

  Sure enough, despite the role her mother once played, Kayavak wasn’t accorded any special status. On the contrary, she entered the pod at the bottom of the pecking order, and there were times when the older whales showed aggression toward her. But, ultimately, she held her own. Gradually she learned to navigate the society of her new pod and became a solid part of the community.

  Even so, Kayavak maintained a bond with all of us. She would throw a glance toward her human companions now and then, as if to let us know she’d made it. We felt as though she were looking back at us with a wink and a nod. Our relationship with her continues to be a special one. Now a young adult, Kayavak is an integral part of the beluga group at the aquarium. A guest wouldn’t be able to pick her out from among the other animals, but every member of the aquarium staff can identify her at a glance.

  Kayavak’s case, with its sad and startling beginning but successful resolution, made a lasting impression on me. Of all the lessons we learned that winter—about nutrition and infectious disease, behavior and environmental enrichment, tough decision making, and acceptance of risk—perhaps the most powerful were the ones we learned from Kayavak. She taught us about adaptability and survival. This endearing whale sought the care and companionship she needed to survive, and we happily provided it.

  ABOUT THE AUTHOR

  Jeff Boehm is a graduate of the University of California, San Diego, where he received his bachelor’s degree, and the University of California, Davis, where he received his degree in veterinary medicine. He completed an internship in small animal medicine in Southern California and then worked as a veterinary clinician at the Los Angeles Zoo. Since 1992, Dr. Boehm has worked at the John G. Shedd Aquarium in Chicago, where he is currently the senior vice president for animal health and conservation science and the Louis Family Conservation chair. In this position, he oversees the aquarium’s veterinary division, a variety of conservation science initiatives, and a Great Lakes conservation program. Dr. Boehm has a keen interest in aquatic conservation, specifically the role that zoos and aquariums play in fieldwork and research, and ultimately in public awareness.

  II

  TECHNOLOGY HELPS

  MRI scans produce excellent images in turtles, lasers limit blood loss during surgery in fish, ultrasound studies can detect heart disease in gorillas, orthopedic surgery works well in birds, and root canals are readily performed on lions, tigers, and bears. All of these animals are monitored during anesthesia with pulse oximetry, a measure of heart rate and blood oxygen saturation. With the help of medical technology, zoo vets arrive at diagnoses earlier, predict outcomes more accurately, and treat symptoms more successfully.

  Given the range of species and potential problems in zoological medicine, there’s sometimes a first-time technological solution. It might be the application of familiar technology to an unfamiliar species, or the replacement of a traditional medical tool with a newer one.

  The process of applying such techniques in wild animals, however, is anything but routine. Even the simplest technique may require a degr
ee of modification, depending on the species. In order to make such adjustments, we collaborate with experts in other medical fields, including domestic and large animal veterinarians, physicians, medical technicians, and veterinary and human dentists. Adding to the challenge, most of our patients must be restrained, anesthetized, or trained for months before they will tolerate even simple technology-based procedures. A sick octopus in need of a set of X-rays, for example, requires three sets of hands and a barrel of water, with a water-soluble anesthetic available as backup.

  Radiography, the production of images using X-rays, is a good example of the application of medical technology in zoological medicine. In both humans and animals, bones and other cartilaginous structures appear white, internal organs appear various shades of gray, and air-filled structures appear black. X-ray images readily show the patient’s skeleton, including its teeth, and the outline of major structures such as the heart, lungs, intestinal tract, liver, kidneys, and bladder.

  The size and density of the animal determines the type of cassette that holds the film and the power required to produce the image. Dental film, the kind we humans bite down on while sitting in a dentist’s chair, works fine for whole-body images of tiny animals like hummingbirds, small fish, and frogs. We use standard-sized X-ray cassettes for small mammals like meerkats and monkeys, or for various body parts of larger animals—the thorax of a wolf, the abdomen of a tiger, the skull of a tapir, or the hoof of a zebra. Whether the exam is performed in a fully equipped veterinary hospital or in the field, the patient is almost always anesthetized or lightly restrained.

  Interpreting the X-ray images poses another challenge. Experience and knowledge of comparative radiographic anatomy are crucial to accurate interpretation, and even then opinions may vary. The radiographic anatomy of a gorilla most resembles that of a human, but with quite a few differences, not the least of which is the size of the hands and skull relative to the body and the presence of air-filled sacs located beneath the neck and in each armpit. Birds have air sacs too, and some of their bones are full of air cavities. But there are many differences among these species as well. An X-ray of a parrot looks very different from that of a hawk.

  With the arrival of digital photography and digital radiography, many zoo vets use e-mail to send radiographs to experts at other institutions for another opinion. As a whole, our profession has been quick to take advantage of the Internet. Not only do we use this tool for communication, it’s often the first place we look for the latest medical technology.

  Zoo vets show their low-and high-tech creativity in the next group of stories: horseshoes give a rhino relief, fiber-optic instruments help pandas, massive portable life-support systems transport whale sharks halfway around the world, orthopedic surgery helps a falcon, and frogs benefit from a new anesthetic method.

  Lucy H. Spelman, DVM

  The Rhino with Glue-On Shoes

  by Lucy H. Spelman, DVM

  There had to be a better way to deal with this rhino’s feet. Blood dripped from Mohan’s foot pads as veterinarians and technicians worked furiously to carve away diseased tissue. These were not small feet—each one measured about ten inches in diameter. A growing pile of soiled gauze and towels littered the floor. Next, bandages would go on. Then we’d roll the rhino over to work on the other side. The blood didn’t worry us. Even if Mo lost a few pints during the trim, the 5,000-pound animal wouldn’t know it.

  In an odd sort of way, we were glad to see red. The blackened, unhealthy tissue wedged between his toes and into the cracks of his soles had outgrown its vascular supply. His back feet were the worst. We trimmed off the outside layers until we got down to healthy tissue, which bled profusely. I watched the foot-trimming team for a minute or so, long enough to gauge how much more anesthesia time they needed. Then I turned my attention back to the rhino. Though we’d done this procedure many times before, it still felt like a big deal to put him under anesthesia.

  At thirty-two, Mo was one of the oldest greater one-horned rhinos in captivity and genetically valuable. When he arrived at the National Zoo, in Washington, DC, in 1998, three years before, everyone hoped that he and Mechi, our female, would breed. He had never bred, and we knew he had a history of foot problems. Unfortunately, the pattern continued. Though the two seemed compatible, Mechi showed more interest in Mo than he did in her and his feet continued to deteriorate.

  Fortunately, Mo handled anesthesia well. He’d stand still for the darting and slump to the ground ten minutes later when the drug took effect. Sometimes he’d go down in the middle of the enclosure, which made it easy. Other times he’d jam his great nose in a corner. We’d reposition him using a few ropes and about a dozen people. I’d put a catheter in his ear, start him on an IV filled with muscle relaxant, and then put a rubber hose up one nostril to deliver oxygen. The minute we had our first set of vital signs, the rest of the team got to work and the trimming began.

  Given his age and the ever-present risk of complications, I tended to keep Mo’s anesthesia on the light side. At the slightest indication of a problem, I could quickly reverse him (wake him up). Since this strategy meant that a loud noise or bright light could cause him to stir, we covered his eyes with a cloth drape, packed his ears with gauze, and kept a syringe full of anesthetic at the ready.

  I lifted the rhino’s blindfold and peered into his big dark eyes. Even anesthetized animals have some sort of facial expression that offers a clue to their mental state. Mo stared past me, unblinking. His eyelids were stretched wide open, a side effect of the anesthetic, just as they should be at this stage in the procedure. I applied a bit more “eye goop,” a sterile ophthalmic ointment, to protect the surface of his corneas, and replaced the cover.

  Checking for an ear twitch, I tickled the hairs in his upside ear. No reaction. Good. A chunk of brown wax stuck to my gloved finger. I fiddled with the hose delivering oxygen. No snort or change in breathing. Our monitors showed a steady heart rate and good blood oxygen saturation. I slipped my hands into his mouth to check his jaw tone; the muscles resisted. He’d definitely need a supplement of anesthetic before the team rolled him onto his other side. Otherwise, he might be able to kick out, or even try to get up. I also got a whiff of bad breath. Maybe we could float (file) his teeth if we had time.

  “How’s it going, Paul?” I asked. A large animal veterinarian, Dr. Paul Anikis had long since become a vital member of our zoo’s consulting team. He’d driven ninety miles into the city from the Virginia countryside early this morning. It was now just past seven-thirty AM.

  “These feet are a mess, Lucy, they really are. We’re gonna try perfusing him today, the way we do in horses. The back feet, anyway. I don’t think oral antibiotics will even touch this stuff.” Paul shook his head. “It seems like these toe pads are the problem. They’ve got to be really sore. If we can get a cephalosporin IV in there, it’ll reduce all that swelling. We’re mixing some up now.”

  When Mo’s feet needed trimming, the rhino’s entire demeanor changed. Normally, he never missed a chance for a food treat or a belly scratch. Erin, one of his keepers, had trained him to stand next to the bars of his indoor enclosure, close enough that she could reach in and work on his feet. While the other keepers distracted him with bits of sweet potato, Erin could give him a mini-pedicure.

  But she could only trim bits of the overgrown tissue. Rhinos have three hooved toes on each foot. The skin between Mo’s toes and the soles of his feet grew abnormally. At a certain point, this tissue fissured and cracked, allowing dirt and bacteria in and causing infection. Then it swelled. Mo couldn’t stand without pinching this infected skin. It hurt. Because the problem affected all four feet, we didn’t always see lameness, but his overall behavior changed. He avoided standing for long periods of time. Instead of enjoying his shower for an hour, for example, he would lie down in the middle of his enclosure. His eyelids and ears drooped. He would rarely come over to the bars. At that point, we’d schedule him for a complete trim under anesth
esia.

  I knelt back down next to the rhino’s huge head, and watched again as Paul worked on the feet. He used a rope to fashion a tourniquet just below the rhino’s tarsal-metatarsal (ankle) joint. Using a short piece of tubing with a needle on the end, a butterfly catheter, he quickly found a vein and injected the medicine. It would flood the tissue of the foot and stay there until he removed the rope. He followed that with some lidocaine, a local anesthetic, to ensure that Mo wouldn’t feel anything.

  For the bandage, Paul started with a combination of cotton and gauze wrap, covered by stretchy material called Vetwrap. We’d been through a fair amount of trial and error with this last step. Our first set of bandages stayed on for only a few hours. Mo got his feet wet and kicked them off. We wanted the bandages to last a day or two, long enough to keep his feet clean immediately after the trim. The answer? Duct tape, of course: the wide gray sticky tape used to patch holes in just about anything. The brand in our kit that day had a clever brand name, Duck Tape, with a picture of a yellow duck standing in a puddle of water.

  The team waited for me to give the rhino a bit more anesthetic and then pushed him up onto his sternum and over onto the other side, folding his legs under his body. Mo’s heavy head rested in my lap during the shift, temporarily pinning me to the floor. Adjusting the blindfold, I checked his eyes again: no change. The extra dose had worked perfectly. I couldn’t resist giving his neck a light pat. His rough skin felt like concrete with a little flex, reminding me of Rudyard Kipling’s description: bumpy plates of armor.