Gillis James D, Penfold Linda M, Mylniczenko Natalie D
South-East Zoo Alliance for Reproduction & Conservation, 581705 White Oak Road, Yulee, FL 32097, USA.
Disney's Animals, Science, and Environment, Disney's Animal Kingdom, The Seas with Nemo and Friends, Walt Disney's Parks and Resorts®, Bay Lake, FL 32830, USA.
Animals (Basel). 2021 Sep 17;11(9):2716. doi: 10.3390/ani11092716.
This study investigated the reproductive biology and sperm cryopreservation of ex situ southern stingrays () by semen collection and characterization and the development and validation of an enzyme-linked immunoassay for plasma total testosterone. Semen was collected in March and June using a manual massage technique, and the ejaculates were assessed for volume, pH, osmolarity, motility, status (0-5 scale: 0 = no forward progression, 5 = rapid linear progression) and total sperm count. Semen was extended in Hank's elasmobranch ringer solution containing 10% DMSO, 10% glycerol or 5% glycerol with 5% N-methylformamide and cryopreserved using a conventional freezing method (-50 °C/min) or a modified slow freezing method (-3 °C/min). Body condition was scored from 1-5 and was noted to be low in March (1.93 ± 0.07) due to feeding practices and increased by June (2.93 ± 0.05) after dietary corrections were made. A concomitant increase ( < 0.05) in plasma total testosterone concentration and sperm motility was noted between March (8.0 ± 7.2 ng/mL, 5.71 ± 2.77%) and June (97.3 ± 11.3 ng/mL, 51.4 ± 14.3%). Samples cryopreserved using a modified slow freeze method (~-3 °C/min) had higher post-thaw motility and plasma membrane integrity than conventionally cryopreserved samples. Data indicate that southern stingray sperm morphometrics adheres to those of other elasmobranch species and that a slow cooling rate may be an avenue of research to improve southern stingray sperm survival during cryopreservation.
本研究通过精液采集与特性分析以及血浆总睾酮酶联免疫分析方法的开发与验证，对异地养殖的南方黄貂鱼（）的生殖生物学和精子冷冻保存进行了研究。于3月和6月采用手动按摩技术采集精液，并对射精量、pH值、渗透压、活力、状态（0 - 5级：0 = 无向前运动，5 = 快速直线运动）和精子总数进行评估。精液在含有10%二甲基亚砜、10%甘油或5%甘油与5% N - 甲基甲酰胺的汉氏板鳃类林格氏溶液中进行稀释，并采用传统冷冻方法（约-50℃/分钟）或改良慢速冷冻方法（约-3℃/分钟）进行冷冻保存。身体状况评分为1 - 5分，由于投喂方式，3月时身体状况评分较低（1.93±0.07），在6月进行饮食调整后有所增加（2.93±0.05）。3月（8.0±7.2 ng/mL，5.71±2.77%）至6月（97.3±11.3 ng/mL，51.4±14.3%）期间，血浆总睾酮浓度和精子活力同时出现增加（<0.05）。采用改良慢速冷冻方法（约-3℃/分钟）冷冻保存的样本解冻后的活力和质膜完整性高于传统冷冻保存的样本。数据表明，南方黄貂鱼精子形态测量符合其他板鳃类物种的特征，缓慢降温速率可能是提高南方黄貂鱼精子冷冻保存存活率的一个研究方向。
