Girndt Antje, Cockburn Glenn, Sánchez-Tójar Alfredo, Løvlie Hanne, Schroeder Julia
Evolutionary Biology, Max Planck Institute for Ornithology, Seewiesen, Germany.
Department of Life Sciences, Imperial College London, Silwood Park Campus, Ascot, United Kingdom.
PLoS One. 2017 Aug 16;12(8):e0182853. doi: 10.1371/journal.pone.0182853. eCollection 2017.
Birds are model organisms in sperm biology. Previous work in zebra finches, suggested that sperm sampled from males' faeces and ejaculates do not differ in size. Here, we tested this assumption in a captive population of house sparrows, Passer domesticus. We compared sperm length in samples from three collection techniques: female dummy, faecal and abdominal massage samples. We found that sperm were significantly shorter in faecal than abdominal massage samples, which was explained by shorter heads and midpieces, but not flagella. This result might indicate that faecal sampled sperm could be less mature than sperm collected by abdominal massage. The female dummy method resulted in an insufficient number of experimental ejaculates because most males ignored it. In light of these results, we recommend using abdominal massage as a preferred method for avian sperm sampling. Where avian sperm cannot be collected by abdominal massage alone, we advise controlling for sperm sampling protocol statistically.
鸟类是精子生物学中的模式生物。先前对斑胸草雀的研究表明，从雄性粪便和射精中采集的精子在大小上没有差异。在此，我们在圈养的家麻雀（Passer domesticus）种群中检验了这一假设。我们比较了通过三种采集技术获得的样本中的精子长度：雌性假鸟法、粪便样本和腹部按摩样本。我们发现，粪便样本中的精子明显短于腹部按摩样本中的精子，这是由于头部和中段较短，但鞭毛长度无差异。这一结果可能表明，粪便样本中的精子可能不如腹部按摩采集的精子成熟。雌性假鸟法获得的实验射精样本数量不足，因为大多数雄性忽视了它。鉴于这些结果，我们建议将腹部按摩作为鸟类精子采样的首选方法。如果仅通过腹部按摩无法采集到鸟类精子，我们建议在统计上对精子采样方案进行控制。
