Exfoliative vaginal cytology: a diagnostic tool for sexual cycle stages in nonhuman primates

Abstract

In Olive baboons (Papio hamadryas anubis) at Lake Manyara National Park (LMNP), a sexually transmitted disease (STD) of unknown aetiology leads to a partial or complete loss of the external genitalia structure. In order to identify the responsible pathogen, sixty-three baboons were temporarily chemically immobilised and sampled. In addition to the main course of the study (identification of the aetiology) and for a maximization of data collection several other aspects were included to the sampling protocol. Thus an exfoliative vaginal cytology (EVC) was performed in 30 females to investigate its application and reliability under field conditions. The appearance of perineal tumescence was compared with the cytological picture of vaginal smears stained with Papanicolaou and Hemacolor. In 23 (77%) of 30 sampled baboon females the cell composition of vaginal cytology matched the perineal swelling stage of the female’s genital skin. It is concluded that EVC is a useful and cost-effective tool for the evaluation of sexual cycle stages in the Olive baboons. However it’s important to note that reliable results can only be obtained if good quality samples are collected and used.

Keywords: Exfoliative vaginal cytology, Papio hamadryas anubis, sexual cycle phase, Papanicolaou staining, Hemacolor staining