Efficiency of vaginal electrical impedance to determine the stage of the reproductive cycle in bitches

A study was carried out to compare the efficiency of vaginal electrical impedance with serum progesterone profile, cytological examination and clinical findings. Vaginal electrical impedance values varied at the different stages of the estrous cycle, with the highest value during the transition into estrous and the lowest in diestrus (P< 0.05). There was a negative statistical correlation between serum progesterone values and the impedance values (36%) (P< 0.001). Vaginal electrical impedance was a faster and cheaper method than progesterone assessment. It was more reliable than vaginal cytology and clinical evaluation. In conclusion, a combination of vaginal electrical impedance measurements and progesterone evaluation was a more useful method for determination of the optimal breeding time in bitches..