Chloro-s-triazine dyes as vital markers in monkeys.

Nine monoand di-chloro-s-triazine (Procion) dyes (Table) have been tested for possible use as vital markers in rhesus monkeys (Macaca mulatta). Goland and Grand (Am J Phys Anthropol 29:201-218, 1968), Prescott, Mitchell, and Fahmy (Am J Phys Anthropol 29:219-224, 1968), and Seiton and Engel (Am J Anat 126: 373-391, 1969) have demonstrated that certain types of reactive dyes are preserved in decalcified sections and act as indicators of osseous growth and growth of the dentition. In this study, each dye was tested for consistency, intensity of marking, and toxic effects. Two to five of the dyes were tested in each of the 36 monkeys; 127 doses (which ranged from 50 to 150 mg/kg of body weight) were administered by multiple injections at four-week intervals. The dyes were injected intravenously in 30 ml sterile water at a rate of 2 ml/minute. The monkeys were killed later by formaldehyde solution (Formalin) perfusion and blocks from the temporomandibular joint, gonial angle, and the body of the mandible were decalcified in formic acid, embedded in celloidin, and sectioned at 10 to 30 micrometers. Brilliant red H-8BS and brilliant purple H3RS were the most effective, because lines of incremental growth were observed easily in newly formed bone and dentin in the unstained decalcified sections. Brilliant orange M-GS was less distinct, and it stained muscle fibers, bone,