Clinic for Birds, Reptiles, Amphibians and Fish, Faculty of Veterinary Medicine, Justus Liebig University Giessen, Frankfurter Strasse 114, Giessen, Germany.
Clinic for Birds, Reptiles, Amphibians and Fish, Faculty of Veterinary Medicine, Justus Liebig University Giessen, Frankfurter Strasse 114, Giessen, Germany.
Theriogenology. 2020 May;148:132-139. doi: 10.1016/j.theriogenology.2020.03.004. Epub 2020 Mar 5.
The St. Vincent amazon (Amazona guildingii) is an endemic parrot on the Carribean island St Vincent. Due to poaching, trade, natural events such as hurricanes and habitat loss the species declined severely throughout the 20th century to a total number of 487 adult individuals and is currently regarded as vulnerable by IUCN. Captive breeding is attempted in terms of species conservation, but reproduction rates have been low due to reproductive problems such as mate aggression, asynchronous reproductive activity and infertile eggs. The aims of the present study were; firstly, to evaluate whether semen analysis might help to assess the fertility of males and to detect potential reasons for infertile eggs; secondly, to increase the number of offspring using artificial insemination, and as a future effect, to increase the presence of genetically valuable males in the ex-situ breeding population. For semen collection electric stimulation was used in 15 mature and healthy St. Vincent amazons with a success rate of 89% (202/227 attempts) in 14/15 males. Quality assessment of the semen included the evaluation of volume, pH, color, consistency and contaminations of the ejaculate, as well as estimation of motility, viability, morphology, concentration and total count of spermatozoa. Semen pH ranged from 6.7 to 7.5. Median sperm motility was 50% and median progressively forward motility 40%. Mean sperm concentration (x¯ ± SD) was 21,313.5 ± 22,408.8 spermatozoa/μl and mean sperm viability 66 ± 16%. Semen samples contained on average 20.5% morphologically normal spermatozoa and sperm malformations were detected mainly in the head (x¯ = 47.6%) and the tail regions (x¯ = 27.7%). Interestingly round bodies were detected in the ejaculates with a mean ratio of 0.6 round bodies per sperm. Semen analysis proved to be very useful to identify males with poor semen quality. Artificial insemination was performed 46 times in 9 females with either individual or pooled semen samples and 13 eggs from 7 females were laid afterwards. In 3 eggs, embryonic development was detected and 1 chick hatched successfully. Paternity testing confirmed the fatherhood of a one-winged semen donor male, a bird which was not able to copulate naturally. The results are very promising and underline that assisted reproduction techniques are a suitable tool for species conservation in captive breeding programs for psittacines.
圣文森特亚马逊鹦鹉（Amazona guildingii）是加勒比海圣文森特岛上特有的一种鹦鹉。由于偷猎、贸易、飓风等自然灾害以及栖息地丧失，该物种在整个 20 世纪数量急剧减少，目前成年个体数量仅为 487 只，被 IUCN 列为易危物种。为了保护物种，人们尝试进行圈养繁殖，但由于配偶攻击、繁殖活动不同步和不孕卵等繁殖问题，繁殖率一直很低。本研究的目的是：首先，评估精液分析是否有助于评估雄性的生育能力，并发现不孕卵的潜在原因；其次，通过人工授精增加后代数量，并作为未来的影响，增加具有遗传价值的雄性在异地繁殖种群中的存在。为了收集精液，对 15 只成熟健康的圣文森特亚马逊鹦鹉进行了电刺激，成功率为 89%（227 次尝试中有 197 次）。精液质量评估包括评估精液的体积、pH 值、颜色、稠度和污染情况，以及估计精子的活力、活力、形态、浓度和总数。精液 pH 值范围为 6.7 至 7.5。精子运动的中位数为 50%，前向运动的中位数为 40%。平均精子浓度（x¯±SD）为 21313.5±22408.8 个/μl，平均精子活力为 66±16%。精液样本中平均有 20.5%形态正常的精子，精子畸形主要发生在头部（x¯=47.6%）和尾部（x¯=27.7%）。有趣的是，在精液中检测到平均每 0.6 个精子有一个圆形体。精液分析被证明是非常有用的，可以识别出精液质量差的雄性。对 9 只雌鸟进行了 46 次人工授精，使用的是单个或混合的精液样本，其中 7 只雌鸟产下了 13 枚卵。在 3 枚卵中检测到胚胎发育，1 只雏鸟成功孵化。亲子关系测试证实了一只单翼精液供体雄性的父亲身份，这只雄性无法自然交配。这些结果非常有希望，并且强调了辅助生殖技术是圈养繁殖计划中保护鹦鹉物种的一种合适工具。
