Poo Sinlan, Hinkson Kristin M, Stege Edward
Department of Research and Conservation, Memphis Zoo, 2000 Prentiss Place, Memphis, TN 38112, USA.
US Fish and Wildlife Services, Leadville National Fish Hatchery, 2846 Highway 300, Leadville, CO 80461, USA.
Reprod Fertil Dev. 2019 Apr;31(4):796-804. doi: 10.1071/RD18073.
Hibernation is an integral part of the life history of species living in seasonal environments. However, our knowledge about the link between hibernation and reproductive success in amphibians remains limited, which poses an obstacle for critical conservation efforts. To fill this gap, we quantified the effects of captive hibernation on sperm quality, sperm quantity and body condition in an endangered anuran, the Wyoming toad (Anaxyrus baxteri), and used naturally hibernated wild toads as a standard for comparison. We hypothesised that hibernation is essential for optimal sperm output but is detrimental to body condition. Sperm collection was performed using assisted reproductive technologies for both captive and wild toads. Contrary to our hypotheses, no differences were observed in sperm metrics (total number of cells, concentration, motility and viability) or in body condition across captive treatment groups (0, 30 or 60 days of hibernation). Moreover, no difference was found between sperm metrics of captive toads and wild toads. These unexpected findings suggest that hibernation may not be an essential process for spermiation in A. baxteri while using exogenous hormones, and illustrate the potential of temperate amphibians to adapt to varying environmental conditions during winter months.
冬眠是生活在季节性环境中的物种生命史的一个组成部分。然而，我们对两栖动物冬眠与繁殖成功之间联系的了解仍然有限，这对关键的保护工作构成了障碍。为了填补这一空白，我们量化了圈养冬眠对濒危无尾两栖动物怀俄明蟾蜍（Anaxyrus baxteri）精子质量、精子数量和身体状况的影响，并将自然冬眠的野生蟾蜍作为比较标准。我们假设冬眠对于最佳精子输出至关重要，但对身体状况有害。使用辅助生殖技术对圈养和野生蟾蜍进行精子采集。与我们的假设相反，在圈养处理组（0、30或60天冬眠）之间，精子指标（细胞总数、浓度、活力和生存力）或身体状况均未观察到差异。此外，圈养蟾蜍和野生蟾蜍的精子指标也没有差异。这些意外发现表明，在使用外源激素时，冬眠可能不是巴氏蟾蜍精子发生的必要过程，并说明了温带两栖动物在冬季适应不同环境条件的潜力。
