Analyses of Two Biomarkers of Collagen II Turnover in Sera of Captive Asian Elephants (Elephas maximus)
1Zoological Society of San Diego, San Diego Zoo’s Wild Animal Park, Escondido, CA, USA; 2Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA, USA; 3Department of Anatomy, Physiology and Cell Biology, School of Veterinary Medicine, University of California, Davis, CA, USA
Presently, there is no effective means of assessing osteoarthritis in elephants before animals show clinical evidence of lameness.4 Typically, osteoarthritis is advanced before joint changes are seen on radiographs.3 Leg radiographs from above the carpus and tarsus are typically non-diagnostic due to size and conformation. Techniques are needed to objectively detect and assess osteoarthritis in elephants before the onset of lameness and pain. The purpose of this study was to investigate the utility of C2C, a collagen II degradation product, and CP II, a collagen II formation product, as biomarkers of osteoarthritis1,2 in Asian elephants using commercially available assays. We compared serum C2C and CPII concentrations in a cross-sectional analyses of non-arthritic (n=33) and arthritic (n=7) Asian elephants and endeavored to elucidate trends in serum marker concentrations during the pre-clinical period and during treatment for the condition. Sera were obtained from Asian elephants at participating U.S. zoos and stored at -80°C until analyses were carried out. Samples were analyzed using commercially available assays (C2C ELISA; CP II ELISA, IBEX Technologies Inc., QC H4P 1P7, Canada) according to manufacturer instructions. Median values of both C2C and CP II were statistically greater in the non-arthritic group than in the arthritic group. These differences were statistically significant; p=0.0002 (C2C) and p=0.039 (CP II), respectively. The study presents a novel approach to the diagnosis of osteoarthritis in Asian elephants. Further studies involving these and other biomarkers are needed to elucidate its usefulness.
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