Abstract

Serum and synovial fluid cytokines have been used to diagnose, assess severity, and monitor treatment response in people and animals with osteoarthritis (OA).^1,3 While synovial fluid collection is not routine in elephants, blood collection is easily accomplished.

Serum inflammatory markers (serum electrophoresis [EPH], amyloid A [SAA], haptoglobin [Hp], tumor necrosis factor alpha [TNF-α], interleukins 1 beta [IL-1β], 6 [IL-6], and 10 [IL-10], interferon gamma [IFN-γ]) and cortisol were monitored in a 42-year-old female Asian elephant (Elephas maximus, elephant 1, E1) with chronic OA during “healthy events,” “stiffness events,” and in relation to Adequan^a treatment. Markers were measured in another elephant (E2) with no evidence of OA.

In E1, acute elevation in TNF-α, IL-1β, IL-10, and chronic elevations in Hp, beta, and gamma globulins decreased following Adequan treatments. Similarly, E1 IL-6 was elevated compared to E2, and decreased to, and remained at, baseline following initial Adequan treatment.^2,3

No obvious changes in E1s TNF, IL-1β, IL-10, IFN-γ, or cortisol occurred in relation to chronic stiffness events or treatments, similar to findings in people.^2-4 Elevated concentrations of IFN-δ were observed throughout the monitoring period.

In E2, IL-6 remained at baseline throughout, despite marked increases in SAA, TNF-α, IL-1B, IL-10, IFN-γ, and cortisol during an illness event. Beta and gamma globulins were elevated throughout.

In conclusion, serum beta and gamma globulins, Hp, TNF-α, IL-1β, IL-6, and IL-10 may be useful in diagnosing, monitoring, and managing OA in elephants. Further investigation into serum and synovial fluid values are warranted and are being pursued.

^aAdequan, Luitpold Pharmaceuticals, Inc., Animal Health Division, Shirley, NY, 11967 USA.
^bProtein 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, 33136 USA.

Acknowledgments

The authors would like to thank the elephant house staff and veterinary staff at National Zoological Park for their assistance in the care and treatment of this elephant.

Literature Cited

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