Methods for predicting sexual maturity in male cynomolgus macaques on the basis of age, body weight, and histologic evaluation of the testes.

In pharmaceutical drug safety testing, sexual maturity is an important experimental parameter. Histologic immaturity of the tissues of the reproductive system can interfere with the interpretation of compound-related effects on the reproductive organs. In female cynomolgus macaques, determination of sexual maturity is simplified by the presence of a menstrual cycle.