Mayor Pedro, Guimaraes Diva Anelie, Lopez-Gatius Fernando, Lopez-Bejar Manel
Department of Animal Health and Anatomy, Faculty of Veterinary, Autonomous University of Barcelona, Edifici V, Campus Universitari de Bellaterra, E-08193 Bellaterra, Spain.
Theriogenology. 2006 Nov;66(8):2001-7. doi: 10.1016/j.theriogenology.2006.06.001. Epub 2006 Jul 11.
The onset of sexual cycle postpartum was described in the collared peccary (Tayassu tajacu). Serum progesterone and 17beta-estradiol profiles, vaginal smears and external genitalia were analyzed in 20 animals housed with their piglets during the first postpartum month. The appearance of external genitalia showed no variation in any of the females: a shallow, reddish vulva, and vaginal mucus were constant features throughout the study. Based on hormonal profiles and vaginal smear cell patterns, 16 (80%) of the 20 peccaries showed signs of estrus and were considered cycling. The remaining four females (20%) did no show signs of estrus confirmed by low levels of progesterone (0.9+/-0.4 ng/mL) during the first postpartum month. In the cycling peccaries, a serum 17beta-estradiol peak (53.4+/-8.1 pg/mL) was observed on Day 7+/-1 postpartum, along with a linear increase in progesterone concentration from 3 (4.3+/-2.6 ng/mL) to 11 (30.8+/-4.9 ng/mL) days after this estradiol peak. Proportions of the different cells of the vaginal epithelium also changed in these females: superficial plus intermediate cells amounted to 76% of the cell total between Days 6 and 9 postpartum, corresponding to the estradiol peak. Nine (56%) of the 16 cycling females mated, indicated by the presence of sperm cells in their vaginal smears, and 6 (67%) became pregnant, reaching term. Non-pregnant cycling females (n=10) showed a steady decrease in serum progesterone concentration from 11 to 23 days after the estradiol peak, when basal levels were attained and a new estradiol peak registered, indicating the resumption of cyclicity in these females. The time interval between the two estradiol peaks was 23.5+/-2.1 days in these females. In pregnant females, progesterone concentrations continued to rise to levels of 60 ng/mL (n=6) 23 days after mating. These findings indicate that the lactating collared peccary female can become cycling and fertile during the early postpartum period, and that a predominance of superficial plus intermediate vaginal cells can be taken as the first sign of estrus.
在领西猯（Tayassu tajacu）中描述了产后性周期的开始。在产后第一个月与仔猪一起饲养的20只动物中，分析了血清孕酮和17β-雌二醇水平、阴道涂片和外生殖器情况。所有雌性动物的外生殖器外观均无变化：整个研究过程中，外阴浅且呈红色，阴道黏液是恒定特征。根据激素水平和阴道涂片细胞模式，20只西猯中有16只（80%）表现出发情迹象并被认为处于性周期中。其余4只雌性（20%）在产后第一个月孕酮水平较低（0.9±0.4 ng/mL），未表现出发情迹象。在处于性周期的西猯中，产后第7±1天观察到血清17β-雌二醇峰值（53.4±8.1 pg/mL），在此雌二醇峰值出现后，孕酮浓度从第3天（4.3±2.6 ng/mL）到第11天（30.8±4.9 ng/mL）呈线性增加。这些雌性动物阴道上皮不同细胞的比例也发生了变化：产后第6至9天，表层加中层细胞占细胞总数的76%，与雌二醇峰值相对应。16只处于性周期的雌性中有9只（56%）交配，阴道涂片中有精子细胞表明了这一点，其中6只（67%）受孕并足月分娩。未怀孕的处于性周期的雌性（n = 10）在雌二醇峰值出现后第11至23天血清孕酮浓度稳步下降，此时达到基础水平并出现新的雌二醇峰值，表明这些雌性恢复了性周期。这些雌性动物两个雌二醇峰值之间的时间间隔为23.5±2.1天。在怀孕的雌性中，交配后23天孕酮浓度持续上升至60 ng/mL（n = 6）。这些发现表明，哺乳期的领西猯雌性在产后早期可进入性周期并具有生育能力，阴道表层加中层细胞占优势可作为发情的首个迹象。
