Abstract

Veterinarians today have more tools available than ever before to manage chronic or painful conditions in their patients. Zoo veterinarians are no exception to this, and with a little homework and flexibility, we can create a system of objective assessment of pain and dysfunction in our animals, and can implement many treatment options to manage discomfort and improve quality of life. This presentation will describe the Houston Zoo’s experience with implementing a standard method of pain or functional assessment, and the variety of treatment modalities we have used at our zoo in the past three years. Oral medications are an important aspect of therapy, but for brevity, will not be discussed in this paper.

With the goal of having a more useful method of assessing patient response to therapy, the Houston Zoo used the Cincinnati Orthopedic Disability Index for Canines (CODI) as a model, and implemented a numerical grading system of patient functional activities. Zookeepers were asked to prioritize five functional activities that they observed the most restriction in in the animals they cared for, and these scores were re-assessed over time to determine an increase or decrease in function. Videos of animals moving or demonstrating restricted functions were captured and stored whenever possible.

The Houston Zoo used a class four, multiwave locked system (MLS) laser^a to treat seventeen zoo patients over a four-month period in 2012. The two primary indications for treatment were lameness/joint pain, and wounds. Though the application of multiple therapies at once makes assessment challenging, a positive result of laser therapy was observed in eight of seventeen patients, with the majority of the positive responses seen in wound patients, rather than lameness/joint pain patients.

The Houston Zoo has treated four patients with autologous stem and regenerative cells (SRC) to improve joint health (a leopard [Panthera pardus], a Malayan tiger [Panthera tigris jacksoni], and a North Sulawesi babirusa [Babyrousa celebensis]) and to reduce immune-mediated inflammation (one lion, Panthera leo). The SRC were prepared using a commercial point-of-care system^b that enables processing of adipose tissue, and re-administration of cells within ninety minutes and one anesthetic event. Again, while the application of multiple therapies at once makes assessment challenging, the joint patients demonstrated improved mobility within one week of treatment and appeared to have improved mobility for the projected duration of effect for SRC administration (approximately nine to twelve months). Two of these patients have had repeated administration of SRC over time and no patients have demonstrated adverse effects.

The Houston Zoo has treated two patients with extracorporeal shockwave therapy (ESWT) to improve joint health and mobility. During ESWT, energy is delivered to a focal point into tissues (up to 10 cm in depth), causing mechanical microstress in cells, resulting in modulation of inflammatory, angiogenic, and osteogenic proteins that assist the natural healing process. Both patients (Malayan tiger, leopard) underwent three anesthetic episodes two to four weeks apart for ESWT treatment. Improvement in gait and function was observed within a week following the third treatments in both animals, though both underwent a combination of therapies, which makes individual assessment of this treatment technique challenging.

Chiropractic adjustments are precise movements at a specific angle with a controlled force aimed at restoring the normal biomechanics and function of the vertebrae or joint. Acupuncture is one type of traditional Chinese medicine that has been in practice for over 4,000 years. Acupoints are stimulated with dry needle acupuncture, laser acupuncture, acupressure, aquapuncture, electroacupuncture, and/or moxibustion. They are very specific points throughout the body that have been correlated with treating certain conditions to help the body restore balance and heal itself. At the Houston Zoo, thirteen current patients, Nigerian dwarf goats (Capra hircus hircus, n=5), a llama (Llama glama), a guinea hog (Sus scrofa scrofa), a North Sulawesi babirusa, a Malayan tiger, a leopard, a black and white ruffed lemur (Varecia variegata variegata), a chimpanzee (Pan troglodytes), and a komodo dragon (Varanus komodensis), have had chiropractic adjustment and ten patients are undergoing routine acupuncture therapy, either via acupuncture laser^c (tiger, leopard, lemur, and babirusa) or traditional acupuncture needles (goats, llama). Treatment is performed by a consulting veterinarian certified in veterinary acupuncture and veterinary chiropractic techniques. Minor subluxations and rotations that were not palpable by standard veterinary assessments have been detected and corrected in several animals (goats, llama, guinea hog, and anesthetized tiger) and have resulted in significant clinical improvement. Over time, the frequency of chiropractic adjustments and acupuncture treatments decreases in most animals as they return to more normal conformation and function. Thus far, zoo patients not under anesthesia have been accepting of the acupuncture treatments and often relax or become sleepy during treatment.

In addition to oral joint supplements, nonsteroidal anti-inflammatory medications, and other oral analgesics, the advanced treatment modalities described above should be considered in zoo patients with chronic musculoskeletal pain. Careful assessment of the patient and overall health status is critical, as is open communication between the veterinary staff and the animal care staff on expectations and follow-up care. As zoo veterinarians, it is our responsibility to provide the highest standard of care for our animals, including the understanding and utilization of both new and centuries-old technologies.

Endnotes

a. Cutting Edge Veterinary Lasers, Fairport, NY, USA www.celasers.com
b. ARC™ system, InGeneron, Inc., Houston, TX, USA
c. MODEL Pointer Pulse handheld pulsed Laser and pulsed T.E.N.S., Lhasa OMS, Inc., Weymouth, MA, USA