Meira C, Ferreira J C, Papa F O, Henry M
Department of Animal Reproduction and Veterinary Radiology, School of Veterinary Medicine and Animal Science-UNESP, Botucatu, SP, Brazil.
Theriogenology. 1998 Jun;49(8):1465-73. doi: 10.1016/s0093-691x(98)00092-2.
The objectives of this study were to determine ovarian activity (with ultrasound) and plasma concentrations of progesterone and estradiol during pregnancy in jennies. There was considerable ovarian activity during the second month of pregnancy. Secondary corpora lutea (total of 2 to 7 per jenny) were formed (mainly by luteinization) starting on Day 41.8 +/- 1.0 (range Days 38 to 46; ovulation = Day 0). The echogenicity of the primary and secondary corpora lutea gradually decreased during pregnancy. Plasma progesterone concentrations increased between Days 0 and 10 (0.9 and 19.9 ng/mL, respectively), gradually decreased to Day 30 (12.1 ng/mL), increased between Days 30 and 40 (plateau, at approximately 17 ng/mL), gradually declined from Days 110 to 160 (nadir of approximately 6 ng/mL), and remained nearly constant until increasing again just before parturition. Plasma estradiol concentrations increased gradually from Day 65, peaked (1.2 ng/mL) on Day 165 (> or = 1 ng/mL on Days 150 to 210), and decreased thereafter, with very low concentrations during the last 20 d before parturition. Ovarian function and hormone profiles were generally similar to those previously reported during pregnancy in mares.
本研究的目的是确定母驴妊娠期间的卵巢活动（通过超声检查）以及孕酮和雌二醇的血浆浓度。妊娠第二个月卵巢活动较为活跃。从第41.8±1.0天（范围为第38至46天；排卵日=第0天）开始形成次级黄体（每头母驴共有2至7个）（主要通过黄体化形成）。妊娠期间，初级和次级黄体的回声性逐渐降低。血浆孕酮浓度在第0天至第10天之间升高（分别为0.9和19.9 ng/mL），到第30天逐渐降至12.1 ng/mL，在第30天至第40天之间升高（平台期，约为17 ng/mL），从第110天至第160天逐渐下降（最低点约为6 ng/mL），并在分娩前再次升高之前几乎保持恒定。血浆雌二醇浓度从第65天开始逐渐升高，在第165天达到峰值（1.2 ng/mL）（在第150天至第210天≥1 ng/mL），此后下降，在分娩前最后20天浓度非常低。卵巢功能和激素水平总体上与之前报道的母马妊娠期间相似。
