Sakaguchi Kenichiro
Laboratory of Veterinary Theriogenology, Joint Department of Veterinary Medicine, Faculty of Applied Biological Sciences, Gifu University, Gifu 501-1193, Japan.
Center for One Medicine Innovative Translational Research (COMIT), Institute for Advanced Study, Gifu University, Gifu 501-1193, Japan.
J Reprod Dev. 2025 Feb 5;71(1):1-9. doi: 10.1262/jrd.2024-091. Epub 2024 Dec 22.
Due to the strong demand for embryo production from young and genotyped superior animals using ovum-pick up (OPU) combined with in vitro fertilization (IVF), the number of in vitro-produced embryos has exceeded that of in vivo-derived embryos globally since 2016. One of the merits of OPU-IVF is that the administration of follicle-stimulating hormone (FSH) is not essential, while FSH treatment prior to OPU promotes oocyte developmental competence. Thus, investigations are needed to optimize OPU-IVF protocols with and without FSH. In addition, OPU enables oocyte collection from antral follicles in living animals. However, there are numerous immature oocytes in follicles at earlier stages, which are potentially destined to degenerate in ovaries. The technology used to foster acquisition of maturational and developmental competences in these immature oocytes is called in vitro growth (IVG). IVG is expected to contribute to assisted reproductive technologies for livestock, humans, and endangered species. However, no offspring from preantral follicles has been reported using IVG in animals other than in mice. Furthermore, IVG can be used to investigate factors affecting the fertility and developmental competence of oocytes by reconstituting follicle growth at each stage in vitro, which cannot be evaluated in vivo. Here, the technological progress of the optimization of immature bovine oocyte utilization is reviewed alongside findings from a variety of other ruminants.
由于对利用采卵（OPU）结合体外受精（IVF）技术从年轻且具有优良基因型的动物生产胚胎有强烈需求，自2016年以来，全球体外生产胚胎的数量已超过体内来源的胚胎。OPU-IVF的优点之一是不需要使用促卵泡激素（FSH），而在OPU前进行FSH处理可提高卵母细胞的发育能力。因此，需要开展研究以优化使用和不使用FSH的OPU-IVF方案。此外，OPU能够从活体动物的窦卵泡中采集卵母细胞。然而，早期卵泡中有大量未成熟卵母细胞，它们可能注定会在卵巢中退化。用于促进这些未成熟卵母细胞获得成熟和发育能力的技术称为体外生长（IVG）。IVG有望为家畜、人类和濒危物种的辅助生殖技术做出贡献。然而，除了小鼠之外，尚未有关于在其他动物中使用IVG从窦前卵泡获得后代的报道。此外，通过在体外重建卵泡各阶段的生长，IVG可用于研究影响卵母细胞生育力和发育能力的因素，而这些因素在体内无法评估。在此，本文综述了未成熟牛卵母细胞利用优化技术的进展以及其他多种反刍动物的研究结果。
