Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, 930 Campus Road, Ithaca, New York 14853, USA.
Namibian Ministry of Environment, Forestry and Tourism, Private Bag 13306, Windhoek, Namibia.
J Wildl Dis. 2021 Apr 1;57(2):357-367. doi: 10.7589/2019-08-202.
Aerial translocation of captured black rhinoceroses (Diceros bicornis) has been accomplished by suspending them by their feet. We expected this posture would compromise respiratory gas exchange more than would lateral recumbency. Because white rhinoceroses (Ceratotherium simum) immobilized with etorphine alone are hypermetabolic, with a high rate of carbon dioxide production (VCO2), we expected immobilized black rhinoceroses would also have a high VCO2. Twelve (nine male, three female; median age 8 yr old [range: 4-25]; median weight 1,137 kg [range: 804-1,234] body weight) wild black rhinoceroses were immobilized by aerial darting with etorphine and azaperone. The animals were in lateral recumbency or suspended by their feet from a crane for approximately 10 min before data were collected. Each rhinoceros received both treatments sequentially, in random order. Six were in lateral recumbency first and six were suspended first. All animals were substantially hypoxemic and hypercapnic in both postures. When suspended by the feet, mean arterial oxygen pressure (PaO2) was 42 mm Hg, 4 mm Hg greater than in lateral recumbency (P=0.030), and arterial carbon dioxide pressure (PaCO2) was 52 mm Hg, 3 mm Hg less than in lateral recumbency (P=0.016). Tidal volume and minute ventilation were similar between postures. The mean VCO2 was 2 mL/kg/min in both postures and was similar to, or marginally greater than, VCO2 predicted allometrically. Suspension by the feet for 10 min did not impair pulmonary function more than did lateral recumbency and apparently augmented gas exchange to a small degree relative to lateral recumbency. The biological importance in these animals of numerically small increments in PaO2 and decrements in PaCO2 with suspension by the feet is unknown. Black rhinoceroses immobilized with etorphine and azaperone were not as hypermetabolic as were white rhinoceroses immobilized with etorphine.
通过悬挂脚来实现捕获的黑犀牛（ Diceros bicornis ）的空运转移。我们预计这种姿势会比侧卧更能影响呼吸气体交换。由于单独使用埃托啡酮固定的白犀牛（ Ceratotherium simum ）新陈代谢过高，二氧化碳产生率（VCO2）很高，我们预计固定的黑犀牛也会有很高的 VCO2。十二只（九只雄性，三只雌性；中位数年龄为 8 岁[范围：4-25]；中位数体重为 1,137 公斤[范围：804-1,234]体重）野生黑犀牛通过埃托啡酮和唑拉西泮的空中飞镖固定。在收集数据之前，动物们侧卧或用起重机悬挂脚约 10 分钟。每只犀牛都以随机顺序先后接受两种治疗。其中 6 只为侧卧，6 只为悬挂。在两种姿势下，所有动物都明显低氧血症和高碳酸血症。当脚悬挂时，平均动脉氧分压（PaO2）为 42mmHg，比侧卧时高 4mmHg（P=0.030），动脉二氧化碳分压（PaCO2）为 52mmHg，比侧卧时低 3mmHg（P=0.016）。两种姿势下潮气量和分钟通气量相似。两种姿势下的平均 VCO2 均为 2mL/kg/min，与根据比例预测的 VCO2 相似，或略高于预测值。脚悬挂 10 分钟不会比侧卧更损害肺功能，并且相对于侧卧，似乎略微增加了气体交换。这些动物中，脚悬挂时 PaO2 略有增加和 PaCO2 略有降低的生物学重要性尚不清楚。用埃托啡酮和唑拉西泮固定的黑犀牛不像用埃托啡酮固定的白犀牛那样新陈代谢过高。
