The long and the short of sperm selection in vitro and in vivo: swim-up techniques select for the longer and faster swimming mammalian sperm
The long and the short of sperm selection in vitro and in vivo: swim-up techniques select for the longer and faster swimming mammalian sperm
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DOI：
10.1111/j.1420-9101.2010.01935.x
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发表时间：
2010-03-01
影响因子：
2.1
通讯作者：
Satake, N.
中科院分区：
文献类型：
--
作者：
Holt, W. V.;Hernandez, M.;Satake, N.
精子竞争和性选择的结果有时被报道为取决于精子的速度和鞭毛长度，这表明精子的形状可能会得到优化，以获得最大的效率。这在很大程度上是一个关于精子性能的未经检验的假设。在这里，我们使用一种“向上游”的选择技术来检验这一想法，将其作为精子在女性体内传输的替代方法，以验证这样一种假设，即精子尾部长度的变化应该通过这种程序来减少。我们在褐兔、猪和公牛的精子中检测到平均鞭毛长度有轻微但显著的增加(P<；0.001)，而方差没有减少。将上游技术应用于猪射精液，证实了所选种群富含快速活动精子。这些影响也反映在活体中，具有短鞭毛和长鞭毛的猪精子能够到达并定植于输卵管精子库。因此，拥有较长鞭毛的好处似乎微乎其微，这表明在体内选择精子是基于更复杂的标准。
Sperm competition and sexual selection outcomes are sometimes reported as depending on sperm velocity and flagellar length, suggesting that sperm shape may be optimized for maximum efficiency. This is a largely unexamined assumption regarding sperm performance. Here, we examine this idea using a 'swim-up' selection technique as a proxy for sperm transport within the female tract, testing the hypothesis that variation in sperm tail length should be reduced by this procedure. We detected small but significant (P < 0.001) increases in mean flagellar length in brown hare, pig and bull spermatozoa without reduction in variance. Applying the swim-up technique to boar ejaculates confirmed that the selected populations were enriched for fast motile spermatozoa. These effects were also reflected in vivo where boar spermatozoa with both short and long flagellae were able to reach and colonize the oviductal sperm reservoir. The benefits of possessing a longer flagellum thus appear to be marginal, suggesting that sperm selection in vivo is based on more complex criteria.