Health Status of Adult Cynomolgus and Rhesus Monkeys Produced by Embryo Splitting

Animals derived from embryo splitting have been successfully produced in livestock farming, and their milk and meat products have entered the human food market. However, although monkeys have been obtained through the same technique, their adult health status remains poorly studied. Here, we performed a comprehensive and systematic evaluation of five adult cynomolgus and two rhesus monkeys derived from embryo splitting, including hematological and biochemical analyses, glucose metabolism assessment, cardiovascular evaluation, bone mineral density examination, brain MRI, and reproductive performance assessment. No significant differences were found in measured parameters between sp-monkeys and controls in cynomolgus monkeys (5 vs. 4), with similar trends in rhesus monkeys. Because only two rhesus sp-monkeys and three rhesus controls were available, the rhesus data were not statistically compared. These results provide no evidence of obvious adverse effects on adult health and offer preliminary support for the safety of this technique in biomedical research.