Use of the fluorochromes xylenol orange, calcein green, and tetracycline to document bone deposition and remodeling in healing fractures in chickens.

The fluorescent calcium binding dyes xylenol orange, calcein green, and tetracycline were used successfully to sequentially label new bone deposition and bone remodeling during the healing of rigidly fixed humeral fractures in the chicken. Xylenol orange and calcein green, administered subcutaneously at 90 mg/kg and 10 mg/kg, respectively, provided easily identified and differentiated bands in newly deposited bone within periosteal and endosteal calluses, intercortical gaps, and screw holes. Tetracycline, administered at 50 mg/kg per os by crop tube, labeled bone faintly in a non-specific manner. Parenteral administration of the same compound might have yielded better results.