Swanson William F
Center for Conservation and Research of Endangered Wildlife, Cincinnati Zoo & Botanical Garden, Cincinnati, OH 45220, USA.
Theriogenology. 2006 Jul 1;66(1):49-58. doi: 10.1016/j.theriogenology.2006.03.024. Epub 2006 May 2.
Assisted reproductive technology (ART), using the primary applied tools of AI, ET, and sperm and embryo cryopreservation, has been promoted over the past decades for its potential to conserve endangered wildlife, including felids. However, if the goal is efficient, consistent production of viable offspring for population management, then the 'potential' of ART has yet to become 'reality' for any non-domestic cat species. For the five small-sized felids (i.e., Brazilian ocelot, fishing cat, Pallas' cat, Arabian sand cat, black-footed cat) managed by Species Survival Plans (SSPs) in North American zoos, achieving this potential may be an absolute necessity if genetically viable captive populations are to be maintained into the next century. Modeling programs suggest that current SSP populations are not sustainable without periodic introduction of new founders and improved demographic parameters, including longer generation intervals and larger population sizes. ART provides the means to address each of these management challenges. In each small cat SSP species, fecal hormone metabolite assays and seminal analysis have proven useful for characterizing basal reproductive parameters, a necessary prerequisite to developing ART. Of the five SSP species, ART has been used to produce living offspring only in the ocelot, including after AI with frozen-thawed spermatozoa and following transfer of frozen-thawed IVF embryos. The true efficacy of these techniques, however, is still unknown. To improve the applicability of ART for population management, priorities for immediate research include further investigation of ovarian stimulation protocols, sperm and embryo cryopreservation methods, embryo culture systems, and fetal and neonatal viability following ART.
辅助生殖技术(ART),运用人工智能、胚胎移植以及精子和胚胎冷冻保存等主要应用工具,在过去几十年里因其保护包括猫科动物在内的濒危野生动物的潜力而得到推广。然而,如果目标是为种群管理高效、稳定地生产出有生存能力的后代,那么对于任何非家猫物种而言,ART的“潜力”尚未成为“现实”。对于北美动物园物种生存计划(SSP)管理的五种小型猫科动物(即巴西豹猫、渔猫、兔狲、阿拉伯沙猫、黑足猫)来说,如果要在下个世纪维持具有遗传活力的圈养种群,实现这种潜力可能是绝对必要的。建模程序表明,如果不定期引入新的奠基动物并改善人口统计学参数,包括延长世代间隔和增加种群规模,目前的SSP种群将无法持续。ART提供了应对这些管理挑战的方法。在每一种小型猫科动物的SSP物种中,粪便激素代谢物检测和精液分析已被证明有助于表征基础生殖参数,这是开发ART的必要前提。在这五种SSP物种中,ART仅用于豹猫并成功产出了活体后代,包括使用冻融精子进行人工授精以及移植冻融体外受精胚胎之后。然而,这些技术的真正效果仍然未知。为提高ART在种群管理中的适用性,当前的研究重点包括进一步研究卵巢刺激方案、精子和胚胎冷冻保存方法、胚胎培养系统以及ART后的胎儿和新生儿活力。