Use of Interleukin Receptor Antagonist Protein (IRAP) in a Multi-Modal Therapeutic Regime for Osteoarthritis in an Asian Elephant (Elephas maximus)
American Association of Zoo Veterinarians Conference 2017

Jessica L. Siegal-Willott1, DVM, DACZM; Paul Anikis2, DVM; Donald L. Neiffer1, VMD, CVA, DACZM; Tony Barthel3, BS; Laurie Goodrich4, DVM, PhD, DACVS

1Department of Wildlife Health Sciences, Smithsonian Institution’s National Zoological Park, Washington, D.C., USA; 2The Piedmont Equine Practice, Inc, The Plains, VA, USA; 3Department of Animal Care Sciences, Smithsonian Institution’s National Zoological Park, Washington, DC, USA; 4Department of Clinical Sciences and Orthopedic Research Center, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, USA


A ∼41-yr-old female Asian elephant (Elephas maximus) experiencing forelimb stiffness and decreased range of motion was diagnosed with bilateral carpal osteoarthritis (OA). Symptomatica and OA specificb treatments had mixed success in alleviating clinical signs.

Standing sedation combined with local anesthesia was employed to deliver ultrasound guided carpal articular injections using an autologous conditioned serum product, interleukin receptor antagonist protein (IRAP)c combined with hyaluronic acid and amikacin. IRAP was delivered into radiocarpal, intercarpal, and carpometacarpal joints bilaterally at 2 wk intervals for three treatments in each joint.1 Symptomatic treatment was assessed using keeper photos, videos, stiffness and mobility charts, and daily observations. Disease treatment was assessed using serial monitoring of complete blood counts, serum chemistries, protein electrophoreses (EPH), amyloid A (SAA), and haptoglobind levels; carpal radiographs; and articular prostaglandin E2 (PGE2)e values.

Following articular injections, increased discomfort lasted ∼24–48 h, then resolved. Within 2 mo of completing therapy, improved range and speed of motion were evident. Decreased inflammation was evidenced by heat degraded protein, SAA, haptoglobin, and PGE2 levels. Improved clinical signs and bloodwork parameters lasted ∼5–6 mo, at which point IRAP was repeated.

Based on the positive symptomatic and disease response noted, autologous therapy using IRAP is recommended for consideration for carpal osteoarthritis in elephants. Serum and joint inflammatory markers were instrumental in gauging response to treatment, progression of disease, and determining when additional treatments were indicated, and should be included in the diagnostic and therapeutic approach to osteoarthritis.


a. Cosequin, Veterinary Sciences, Inc, Lancaster, SC, USA; gabapentin, Actavis Pharma, Inc, Parsippany, NJ, USA; ibuprofen, Amneal Pharmaceuticals, Bridgewater, NJ, USA; Gastrogaurd, Merial, Inc, Duluth, GA, USA

b. Legend, Merial, Inc, Duluth, GA, USA; Adequan, Luitpold Pharmaceuticals, Inc, Animal Health Division, Shirley, NY, USA

c. Interleukin receptor antagonist protein, Dechra Veterinary Products, Overland Park, KS, USA

d. Protein electrophoresis, serum amyloid A, and haptoglobin measurements performed at Acute Phase Protein Laboratory, Division of Comparative Pathology, Miller School of Medicine, University of Miami, Miami, FL, USA

e. Prostaglandin E2 measurements performed at the Orthopedic Research Center, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, USA


The authors would like to thank the elephant house staff and veterinary staff at National Zoological Park, Dr. Betsy Herrelko, Nikki Phillips, and Karen Dailey for their assistance in the care and treatment of this elephant.

Literature Cited

1.  Textor J. Autologous biologic treatment for equine musculoskeletal injuries: platelet-rich plasma and IL-1 receptor antagonist protein. Vet Clin North Am Equine Pract. 2011;27:275–298.


Speaker Information
(click the speaker's name to view other papers and abstracts submitted by this speaker)

Jessica L. Siegal-Willott, DVM, DACZM
Department of Wildlife Health Sciences
Smithsonian Institution’s National Zoological Park
Washington, D.C., USA

MAIN : Elephant & Rhinoceros : IRAP in Multi-Modal Therapeutic for OA in Elephant
Powered By VIN