Rowell J E, Flood P F
Department of Veterinary Anatomy, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Canada.
J Reprod Fertil. 1988 Sep;84(1):117-22. doi: 10.1530/jrf.0.0840117.
Progesterone, oestradiol-17 beta and LH were measured in plasma from 6 non-pregnant, captive, female muskoxen during the 1984 and 1985 breeding seasons. Jugular blood samples were taken on an alternating 3/4-day schedule in 1984 and daily or at 4-h intervals over oestrus, via indwelling jugular cannulae, for 6 weeks in 1985. Oestrous cycle length was 19.6 +/- 0.96 (s.d.) days (n = 19) and did not vary between the first and subsequent cycles of the season. Progesterone was lowest at oestrus (less than or equal to 0.1 ng/ml), began to rise on Days 4-5, peaked on Days 10-12 (mean = 2.6 ng/ml) and returned to baseline 2-5 days before the next oestrus. A small rise in progesterone before the first cycle of the breeding season was observed on 7 of 12 occasions. Oestradiol-17 beta was significantly higher (P less than 0.001) 1-4 days before, or coincident with, oestrus. The average duration of the LH peak was 24.6 h (n = 7) and coincided with observations of behavioural oestrus. In one animal behavioural oestrus and an LH peak preceded a small progesterone rise at the beginning of the breeding season. The temporal relationship of these three hormones during the muskox oestrous cycle is very similar to that seen in domestic ruminants.
在1984年和1985年繁殖季节，对6头圈养的非妊娠雌性麝牛的血浆中的孕酮、雌二醇 - 17β和促黄体生成素（LH）进行了测定。1984年，每隔3/4天采集一次颈静脉血样；1985年，通过留置颈静脉套管，在发情期每天或每隔4小时采集一次血样，持续6周。发情周期长度为19.6±0.96（标准差）天（n = 19），在该季节的第一个周期和后续周期之间没有变化。孕酮在发情期最低（≤0.1 ng/ml），在第4 - 5天开始上升，在第10 - 12天达到峰值（平均 = 2.6 ng/ml），并在下一次发情前2 - 5天恢复到基线水平。在繁殖季节第一个周期前，12次中有7次观察到孕酮有小幅上升。雌二醇 - 17β在发情前1 - 4天或与发情同时显著升高（P < 0.001）。促黄体生成素峰值的平均持续时间为24.6小时（n = 7），与行为发情的观察结果一致。在一只动物中，行为发情和促黄体生成素峰值在繁殖季节开始时孕酮小幅上升之前出现。麝牛发情周期中这三种激素的时间关系与家养反刍动物中观察到的非常相似。
