雌性印太瓶鼻海豚（Tursiops aduncus）生殖激素积聚规律研究

Reproduction in cetaceans is characterized by a cycle of events regulated by both nervous and endocrine systems. In cetaceans, determination of reproductive status through hormones detection is an important tool to investigate their reproduction biology. Previous studies about reproductive hormones in these mammals seem to be limited by sampling collection and systematic data acquisition, especially on certain cetacean species. Consequentially, most species-specific results are scattered and opportunistic, and additional studies are necessary to acquire detailed information. The Indo-Pacific bottlenose dolphin (Tursiops aduncus) is an international common species for scientific research on reproductive biology and artificial breeding, compare to the majority of other cetacean species. Therefore, scientists are well aware of the reproductive system of this species, but few information is available in relation to reproductive hormones in female Indo-Pacific bottlenose dolphin. In the present study, we will monitor serum progesterone and estradiol concentration characters in female Indo-Pacific bottlenose dolphins under human care through enzyme-linked fluorescent assay. The main aim of our project will be to reveal the hormones concentration values and fluctuate profiles at different productive status of sex maturity, seasonal estrus, and gestation. Furthermore, we want to complete and built the database of reproductive hormones concentration characters at different reproductive status in female Indo-Pacific bottlenose dolphins. Towards our objectives, we will (i) fill current knowledge gaps about this species and then achieve our expected aims determining reproductive status of the Indo-Pacific bottlenose dolphin through reproductive hormones detection; (ii) guide the artificial breeding program of the Indo-Pacific bottlenose dolphin; and (iii) provide help in wild population reproduction investigation.

鲸类繁殖是受神经和内分泌系统双重调节的周期性行为，通过对生殖激素监测判断鲸类生殖状态是鲸类繁殖研究的重要方式。取样问题和研究的系统性一直都是制约鲸类生殖激素监测研究的瓶颈，存在单个物种研究不系统、不深入的问题。印太瓶鼻海豚（Tursiops aduncus）是国际上鲸类繁殖研究开展较多的物种，其繁殖相关的问题大多已得到解答，但生殖激素在雌性个体繁殖过程中的积聚特点尚未见报道。本研究拟利用酶联荧光测定技术对不同生殖状态下雌性印太瓶鼻海豚血清孕酮和雌二醇浓度进行监测，以揭示该物种性成熟、季节性发情和妊娠期等不同生殖状态下的生殖激素浓度和积聚规律，完善和建立雌性印太瓶鼻海豚生殖激素积聚特点和生殖状态间的对应关系。本研究成果不仅可以填补雌性印太瓶鼻海豚在生殖激素方面的研究空缺，达到通过生殖激素监测判断动物生殖状态的目的；同时可为印太瓶鼻海豚的人工繁殖保护提供指导；也为野外种群的繁殖监测提供借鉴。

鲸类是哺乳动物适应水生环境的特殊类群，它们在由陆生到水生的进化过程中演化出了独特的环境适应性繁殖策略。监测鲸类的生殖状态（性成熟、发情、妊娠、哺乳等）是科研人员研究鲸类繁殖策略的主要手段和途径。建立生殖激素变化规律与动物生殖状态的对应关系，通过生殖激素浓度监测判断动物生殖状态，不仅是鲸类生殖激素研究的主要内容，也是鲸类繁殖策略研究的重要手段。. 本研究以香港海洋公园中饲养的12头雌性印太瓶鼻海豚（Tursiops aduncus）为研究对象，研究其血清孕酮，雌二醇，睾酮的含量。结果显示，圈养的印太瓶鼻海豚的青春期从5岁开始，在6岁达到性成熟，性成熟未孕雌性个体血清孕酮的平均浓度为0.33(0.25-0.97)ng/mL（四分位距），显著高于未成熟个体中的浓度0.26(0.25-0.38)ng/mL。研究还发现，青春期个体血清中雌二醇的浓度(9.5±1.7pg/mL，±SD)，与未达青春期个体雌二醇的浓度(低于检出限9pg/mL)存在显著差异。成年个体孕酮含量在二月到十月期间较高0.38(0.25-1.07)ng/mL，推测印太瓶鼻海豚存在较弱的季节性繁殖规律。妊娠期间，血清孕酮含量变化范围从10.54±8.74ng/mL(indexed month post-conception [IMPC] 0)至25.49±12.06ng/mL(IMPC2)，并呈现双峰模式，一个浓度峰值出现在妊娠早期25.49±12.06ng/mL(IMPC2)，另一个浓度峰值出现在妊娠晚期(21.71±10.25ng/L，IMPC12)。妊娠早期血清雌二醇很少被检测到，从妊娠中期(9.45±1.83pg/mL)到妊娠后期(11.88±3.81pg/mL)雌二醇浓度持续增加，并在生产前一个月达到峰值(15.45±6.78pg/mL)。血清睾酮在妊娠期IMPC 7时浓度(0.36±0.10ng/mL)达到峰值，并显著高于一年中其他月份的浓度(0.16±0.10ng/mL)。本研究提供了雌性印太瓶鼻海豚不同生殖状态下生殖激素浓度范围和变化规律，为该物种的人工繁殖和野外种群的保护提供数据支撑。