Abstract: Three methods for early pregnancy diagnosis in cynomolgus monkey are compared to find out an accurate and reliable one. Cynomolgus monkeys were examined by rectal palpation, B ultrasound and progesterone testing on 20 days of gestation (GD) for early pregnancy diagnosis, and pregnancy is confirmed by B ultrasound examination on GD20. The accuracy of B ultrasound was 96.4%; the accuracy of rectal palpation was 92.9%; the accuracy of progesterone testing was 64.3%. B ultrasound with highest accuracy is gold standard method of pregnancy diagnosis in cynomolgus monkeys; rectal palpation is accurate, convenient and economical, which is suitable for large quantities of diagnosis; progesterone test with low accuracy can be used as a secondary method of early pregnancy diagnosis.

Key words: cynomolgus monkey; early pregnancy diagnosis; B ultrasound; rectal palpation; progesterone