Estimation of Ovulation and Optimal Breeding Time Based on Vaginal Cytology and Determination of Reproductive Hormones in Shih-tzu Bitches
Shit-tzu견에서 발정 주기, 교배 적기 및 배란 시기를 정확하게 추정하기 위한 질 세포 검사를 확립하기 위하여 Shih-tzu 견 12두를 대상으로 발정 주기동안 질 세포 검사 및 estradiol-와 progesterone 농도를 측정하여 다음과 같은 결과를 얻었다. 발정주기별 질 세포상의 특징적인 변화로서 발정 전기에는 무핵 세포와 적혈구, 발정기에는 표층 세포와 무핵 세포 및 적혈구가 주종을 이루는 세포였으며 발정 휴지기에는 소형 중간 세포와
Vaginal cytology was examined in 12 Shih-tzu bitches to establish the accurate basic data for estimate to the optimal mating time and ovulation time. The mean duration of proestrus and estrus were days and days in pregnant bitches. The gestational length in the 12 pregnant bitches was days in pregnant bitches when Day 0 was timed from the first day of male acceptance. Characteristic features of vaginal cytology during the estrous cycle were the high proportion of large intermediate cell, superficial cell, anuclear cell and erythrocyte in proestrus, superficial cell, anuclear cell and erythrocyte in estrus, and parabasal cell, small and large intermediate cell and leukocyte in diestrus, respectively. Cornification index (CI) was the high proportion in proestrus and estrus, then it decreased in diestrus and anestrus. When Day 0 was timed from the day of the first male acceptance, the CI peak was Day 2 and maintained above 80% between Day -4 and Day 6 during 11 days, and above 90% between Day -1 and Day 5 during 7 days. In relationship between CI and reproductive hormones, CI showed peak at the first day after plasma estradiol- concentration peak and plasma progesterone concentration was first increased above 4.0 ng/ml at Day 0 which was the first day after CI peak. In conclusion, ovulation in Shih-tzu bitches occurred at the first day after CI peak. Vaginal cytology is the simple and reliable method for estimating estrous cycle, optimal breeding time and ovulation time in Shih-tzu bitches.