Danish researchers have been investigating a novel technique for evaluating joint disease. This involves the serial evaluation of cartilage-derived retinoic acid protein (CD-RAP) levels in individual horses as a measure of cartilage synthesis and/or regeneration.

Sensitive and specific tests are urgently needed in both human and veterinary medicine to detect early changes in joint cartilage. One way researchers are doing this is by identifying specific "markers" found in synovial fluid, serum (blood), and urine. 

CD-RAP is the latest molecule to be studied as a potential "marker" for joint disease in horses, according to a study out of the University of Copenhagen.

In this inaugural study of CD-RAP in horses, the researchers used a commercial test kit to detect the potential marker in all of the horses in the study, but they noted large intra- and inter-assay variations in CD-RAP concentrations (14.0 to 45.5%)