South-East Zoo Alliance for Reproduction & Conservation, Yulee, FL, USA.
Adv Exp Med Biol. 2019;1200:465-488. doi: 10.1007/978-3-030-23633-5_15.
Sharks and rays make up 96% of the class Chondrichthyes. They are among the most endangered of any taxa, threatened through habitat loss, overfishing and hunting for shark fin soup, traditional medicines or sport, and because many species are slow to mature and produce low numbers of offspring. Sharks and rays are ecologically and reproductively diverse, though basic knowledge of their reproductive physiology is lacking for many species. There has been a move towards non-lethal approaches of data collection in sharks and rays, especially with reproductive technologies such as ultrasound and hormone analysis. Additionally, technologies such as semen collection and artificial insemination are lending themselves to develop tools to manage small or closed populations, with cold-stored sperm being shipped between institutions to maximize genetic diversity in managed populations. The role of steroid hormones in elasmobranch reproduction appears broadly conserved, though heavily influenced by environmental cues, especially temperature. For this reason elasmobranchs are likely at risk of reproductive perturbations due to environmental changes such as ocean warming. Current reproductive technologies including computer assisted sperm assessments to study warming effects on sperm motility and intra-uterine satellite tags to determine birthing grounds will serve to generate data to mitigate anthropogenic changes that threaten the future of this vulnerable groups of fish.
鲨鱼和鳐鱼构成软骨鱼纲的 96%。它们是所有分类中受威胁最严重的物种之一，面临着栖息地丧失、过度捕捞、猎鲨取鳍、传统药物或运动的威胁，而且许多物种成熟缓慢，繁殖后代数量较少。鲨鱼和鳐鱼在生态和繁殖方面具有多样性，但许多物种的生殖生理学基础知识仍然缺乏。人们已经开始在鲨鱼和鳐鱼中采用非致命的方法来收集数据，特别是在超声和激素分析等生殖技术方面。此外，精液采集和人工授精等技术也有助于开发工具来管理小型或封闭的种群，冷藏的精子在机构之间运输，以最大限度地提高管理种群的遗传多样性。类固醇激素在软骨鱼类生殖中的作用似乎广泛保守，但受环境线索的影响很大，尤其是温度。因此，由于海洋变暖等环境变化，软骨鱼类可能面临生殖紊乱的风险。目前的生殖技术包括计算机辅助精子评估，以研究升温对精子活力的影响，以及宫内卫星标签，以确定分娩地点，这些技术将有助于生成数据，以减轻威胁这些脆弱鱼类群体未来的人为变化。
