Pathiraja N, Oyedipe E O, Gyang E O, Obasi A
National Animal Production Research Institute (N.A.P.R.I.), Ahmadu Bello University, Shika, Zaria, Nigeria.
Br Vet J. 1991 Jan-Feb;147(1):57-62. doi: 10.1016/0007-1935(91)90067-W.
Twenty-five 2-3-year-old cycling does weighing 17-25 kg were obtained from semi-nomadic farmers and managed under controlled conditions while simulating the traditional management system. Oestrus was synchronized using progestogen impregnated vaginal pessaries. Blood samples were collected daily for progesterone assay from the day of pessary withdrawal up to one complete oestrous cycle. Oestrus was checked twice daily using vasectomized bucks. Ovulation rate was determined by direct observation of the ovaries following laparotomy on day 5-7 of the oestrous cycle. Following oestrus synchronization, mean ovulation rate was 1.68 +/- 0.13. Mean oestrous cycle length and duration of oestrus were 21.30 +/- 0.28 days and 21.37 +/- 0.24 hours respectively. Plasma progesterone concentrations ranged from non-detectable levels on the day of oestrus to 5.2 +/- 0.28 ng ml at mid-cycle. The duration of elevated progesterone level (greater than 2 ng/ml) was about 12 days. The peak progesterone values did not differ between animals with different ovulation rates. However, the plasma progesterone concentration during the early cycle (days 0-6) was significantly lower in the single ovulators compared with others. There were no major differences in plasma progesterone levels during the oestrous cycle of Red Sokoto does with different ovulation rates.
从半游牧农民那里获取了25只体重17 - 25千克、年龄在2 - 3岁的母山羊，在模拟传统管理系统的条件下进行饲养管理。使用含孕激素的阴道栓剂使发情同步。从取出栓剂之日起直至一个完整发情周期，每天采集血样进行孕酮测定。每天用输精管结扎的公羊检查两次发情情况。在发情周期的第5 - 7天进行剖腹手术，通过直接观察卵巢来确定排卵率。发情同步后，平均排卵率为1.68±0.13。平均发情周期长度和发情持续时间分别为21.30±0.28天和21.37±0.24小时。血浆孕酮浓度从发情当天的不可检测水平到周期中期的5.2±0.28纳克/毫升不等。孕酮水平升高（大于2纳克/毫升）的持续时间约为12天。不同排卵率的动物之间孕酮峰值没有差异。然而，与其他动物相比，单排卵动物在周期早期（第0 - 6天）的血浆孕酮浓度显著较低。不同排卵率的红索科托母山羊在发情周期中的血浆孕酮水平没有重大差异。
