Theriogenology Department, Faculty of Veterinary Medicine, Matrouh University, Matrouh 51512, Egypt.
Animal and Fish Production Department, Faculty of Agriculture (El-Shatby), Alexandria University, Alexandria 21545, Egypt.
Anim Reprod Sci. 2022 Sep;244:107044. doi: 10.1016/j.anireprosci.2022.107044. Epub 2022 Jul 25.
The present study was designed to evaluate the efficiency of GnRH-loaded chitosan-TPP nanoparticles (GnRH-CsNPs) to improve the reproductive performance of anestrus buffaloes during the summer. Egyptian buffaloes (n = 50) were synchronized for estrus either with the ovsynch protocol (OVSs, n = 20) or with the modified ovsynch protocol (OVSm, n = 30) using GnRH-CsNPs. Sera samples were collected on days 0, 7, and 10 (insemination day); and days15 and 30 post insemination for estradiol (E) and progesterone (P) determination. The follicles were monitored on day 0 and day 10. CLs diameter and pregnancy diagnosis were scanned on day 30 post insemination. Using a half dose of GnRH as GnRH-CsNPs in the OVSm improved (P < 0.05) the number of total and large follicles, and the total surface area of subordinate and large follicles compared to the OVSs protocol. The OVSm increased (P < 0.05) the largest follicles diameter on day 10 and CLs diameter on day 30 post insemination compared to the OVSs protocol. E concentration was greater (P < 0.05) on insemination day, and P concentrations were higher (P < 0.05) on days 15 and 30 post insemination in the OVSm than in the OVSs. The estrus induction rate was 80 % higher (P < 0.05) in the OVSm and cows exhibited estrus within 17.54 h earlier than the OVSs (50 % within 42 h), respectively. The conception rate increased in OVSm compared to OVSs (75 vs. 40 %, respectively). In conclusion, nanofabrication of GnRH allowed to reduce hormonal dose to 50 % without any adverse effects on fertility, and improved ovarian activity and reproductive performance of anestrus buffaloes during the low breeding season.
本研究旨在评估 GnRH 负载壳聚糖-TPP 纳米粒（GnRH-CsNPs）提高夏季乏情埃及水牛繁殖性能的效率。采用 GnRH-CsNPs 通过 Ovsynch 方案（OVS，n=20）或改良 Ovsynch 方案（OVSm，n=30）对 50 头埃及水牛同期发情。发情当天和发情后第 7、10 天（输精日）以及第 15、30 天采集血清样品，测定雌二醇（E）和孕酮（P）。发情当天和发情后第 10 天监测卵泡。发情后第 30 天扫描黄体直径和妊娠诊断。OVSm 中 GnRH-CsNPs 采用半剂量 GnRH 可增加（P<0.05）总卵泡和大卵泡数量以及后备卵泡和大卵泡总面积。与 OVSs 方案相比，OVSm 可增加发情后第 10 天最大卵泡直径和发情后第 30 天黄体直径（P<0.05）。OVSm 中发情当天的 E 浓度更高（P<0.05），发情后第 15 和 30 天的 P 浓度更高（P<0.05）。OVSm 发情诱导率提高了 80%（P<0.05），发情牛在 OVSs 发情后 17.54 小时（50%在 42 小时内）前发情。OVSm 中的受孕率高于 OVSs（分别为 75%和 40%）。总之，GnRH 的纳米制造允许将激素剂量减少到 50%，而不会对生育能力产生任何不利影响，并改善了低繁殖季节乏情埃及水牛的卵巢活动和繁殖性能。
