Modified Vaginal Sampling Technique Reduces Interference on Estrous Cycle’s Phases of Rats

Aims: Two sampling techniques are used in preparing rodent vaginal smear. These techniques include vaginal lavage with sterile fluid using an eye dropper or a pipette and swab with moistened cotton bud with sterile fluid. The current study aims to investigate the influence of the different techniques of vaginal sampling on estrous cycle (EC) regularity.

Study Design: Four groups of adult female rats, each consisting of 10 animals, were selected for the study.

Methodology: Vaginal samples were obtained using different techniques including cotton bud, eye dropper, pipette, and modified pipette for four animal groups during six ECs.

Results: The modified pipette technique showed less influence on EC regularity in rats compared with the other techniques. The modified pipette animal group showed a significantly (p < 0.05) higher percentage of animals with regular ECs (98±4.1) compared with the cotton bud animal group (75.0±13.8).

Conclusion: The modified pipette technique has less interference on the EC phases of rats than the other techniques, and it does not require assistance compared with the pipette technique.