Swelum Ayman Abdel-Aziz, Saadeldin Islam M, Moumen Abdullah, Ba-Awadh Hani, Alowaimer Abdullah N
Department of Animal Production, College of Food and Agriculture Sciences, King Saud University, P.O. Box 2460, Riyadh 11451, Saudi Arabia; Department of Theriogenology, Faculty of Veterinary Medicine, Zagazig University, Sharkia 44519, Egypt.
Department of Animal Production, College of Food and Agriculture Sciences, King Saud University, P.O. Box 2460, Riyadh 11451, Saudi Arabia; Department of Physiology, Faculty of Veterinary Medicine, Zagazig University, 44519 Zagazig, Egypt.
Theriogenology. 2018 Sep 15;118:203-211. doi: 10.1016/j.theriogenology.2018.06.008. Epub 2018 Jun 18.
The reproductive efficiency of camels can be improved using artificial insemination and embryo transfer programs that require a dependable method for synchronization of follicular waves. This study aimed to evaluate the efficacy of a progesterone-releasing intravaginal device (PRIDΔ) to induce synchronization for the follicular wave in Camelus dromedarius during the rutting season, by ovarian monitoring, assessing sexual receptivity and fertility, and quantifying progesterone (P4) and estradiol (E2) concentrations. Twenty animals received a new PRIDΔ with 1.55 g of P4 for 2 wk (Day 14); another 20 camels were used as the control. Ultrasound ovarian monitoring and camel sexual receptivity were evaluated each day during the course of the experiment for all camels in the two groups. The proportion of animals in the ovulatory (follicle diameter: 12 to 18 mm) and non-ovulatory phases was calculated according to the ovarian monitoring results using ultrasound. Blind natural mating occurred on Day 16, and ovulation, non-return, and fertility rates were calculated. Blood samples were collected. Serum P4 and E2 levels were measured daily during the trial period (21 d) using ELISA kits. The results revealed that the proportion of females in the ovulatory phase on Day 16 in the PRIDΔ group was significantly higher than that in the control group (85 and 50, respectively). Serum P4 levels increased significantly after PRIDΔ insertion and reached the maximum values (5.47, 5.02, 5.55, and 4.88 ng/mL) on Days 4, 5, 6, and 7, respectively. P4 levels significantly decreased after PRIDΔ removal and reached the minimal levels (1.23 and 0.67 ng/mL) on Days 15 and 16, respectively. There was no significant difference in the E2 levels between the groups. Ovulation, non-return, and fertility rates in inseminated camels were significantly higher in the PRIDΔ group (85%, 80%, and 75%, respectively) than in the control group (50%, 45%. and 45%, respectively). In the control group, the P4 level was maintained at a minimal level (≥1 ng/mL). In conclusion, the treatment of dromedary camels with PRIDΔ led to a uniform increase in serum concentrations of P4; however, it could not stop follicular growth. After PRIDΔ removal, P4 concentrations dropped and stimulated the development of a new follicular wave; most female camels were in the ovulatory phase 2 d after PRIDΔ removal. Therefore, PRIDΔ is efficient at inducing follicular wave synchronization in C. dromedarius with good fertility.
使用人工授精和胚胎移植程序可以提高骆驼的繁殖效率，而这些程序需要一种可靠的方法来同步卵泡波。本研究旨在通过卵巢监测、评估性接受能力和生育力以及定量孕酮（P4）和雌二醇（E2）浓度，评估孕酮释放阴道内装置（PRIDΔ）在发情季节诱导单峰驼卵泡波同步的效果。20只动物接受了含1.55 g P4的新型PRIDΔ，持续2周（第14天）；另外20只骆驼作为对照。在实验过程中，每天对两组所有骆驼进行超声卵巢监测和骆驼性接受能力评估。根据超声卵巢监测结果计算排卵期（卵泡直径：12至18 mm）和非排卵期动物的比例。在第16天进行盲法自然交配，并计算排卵率、返情率和生育率。采集血样。在试验期（21天）内，每天使用酶联免疫吸附测定试剂盒测定血清P4和E2水平。结果显示，PRIDΔ组第16天处于排卵期的雌性比例显著高于对照组（分别为85%和50%）。插入PRIDΔ后血清P4水平显著升高，分别在第4、5、6和7天达到最大值（5.47、5.02、5.55和4.88 ng/mL）。取出PRIDΔ后P4水平显著下降，分别在第15和16天达到最低水平（1.23和0.67 ng/mL）。两组间E2水平无显著差异。PRIDΔ组人工授精骆驼的排卵率、返情率和生育率显著高于对照组（分别为85%、80%和75%）（对照组分别为50%、45%和45%）。在对照组中，P4水平维持在最低水平（≥1 ng/mL）。总之，用PRIDΔ治疗单峰驼导致血清P4浓度均匀升高；然而，它不能阻止卵泡生长。取出PRIDΔ后，P4浓度下降并刺激新卵泡波的发育；大多数雌性骆驼在取出PRIDΔ后2天处于排卵期。因此，PRIDΔ在诱导单峰驼卵泡波同步方面有效，且生育力良好。
