Yuen Queeny W H, Brook Fiona M, Kinoshita Reimi E, Ying Michael T C
Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hung Hom, Hong Kong SAR, China.
J Androl. 2009 Jul-Aug;30(4):432-9. doi: 10.2164/jandrol.108.006692. Epub 2009 Jan 22.
The testes of sexually mature dolphins produce large quantities of sperm. Sperm are expelled in copious amounts of seminal fluid through repeated ejaculations that can occur within a short period of time. There is currently a lack of detail about the methodology of sequential ejaculate collection in dolphins and how the traits of individual ejaculates affect the assessment of reproductive capacity. The objectives of this study were to obtain series of ejaculates from 3 dolphins by following a well-defined collection protocol and then to characterize individual ejaculates. Semen was collected weekly for 1 year from 3 sexually mature Tursiops aduncus. The end of a collection session was marked by a lack of semen, in spite of effort, or micturition. Individual ejaculates were analyzed for volume, pH, and sperm concentration, count, motility, and viability following methods previously described for dolphin semen. The first ejaculate was typically higher in volume and sperm count but lower in sperm concentration, motility, and viability. The concentration of the second ejaculate was generally the highest. Sperm motility and viability of the second and subsequent ejaculates in a series were good (ie, >80%). Collection of the first ejaculate only can lead to underestimation of reproductive capacity. Sperm output fluctuated erratically from week to week, so it was difficult to assess any seasonal pattern. Results provide information for further investigation of male dolphin reproductive patterns and any effect of collection frequency on ejaculate characteristics.
性成熟海豚的睾丸会产生大量精子。通过在短时间内反复射精，精子会随着大量精液排出。目前，关于海豚连续射精采集方法以及个体射精特征如何影响生殖能力评估的细节尚缺。本研究的目的是按照明确的采集方案从3只海豚获取一系列射精样本，然后对个体射精样本进行特征描述。从3只性成熟的糙齿海豚中，每周采集精液，持续1年。采集过程结束的标志是尽管努力但仍无精液排出或出现排尿。按照先前描述的海豚精液分析方法，对个体射精样本的体积、pH值、精子浓度、数量、活力和存活率进行分析。首次射精的体积和精子数量通常较高，但精子浓度、活力和存活率较低。第二次射精的浓度通常最高。系列射精样本中第二次及后续射精的精子活力和存活率良好（即>80%）。仅采集首次射精样本可能会低估生殖能力。精子产量每周波动不定，因此难以评估任何季节性模式。研究结果为进一步研究雄性海豚的生殖模式以及采集频率对射精特征的任何影响提供了信息。
