Adamovicz Laura, Leister Katie, Byrd John, Phillips Christopher A, Allender Matthew C
Wildlife Epidemiology Lab, Department of Veterinary Clinical Medicine 2001 S. Lincoln Ave., Urbana, IL 61802, USA.
Clinch River Environmental Studies Organization Oak Ridge, TN, USA.
Conserv Physiol. 2018 Jul 25;6(1):coy041. doi: 10.1093/conphys/coy041. eCollection 2018.
Sustainable wildlife populations depend on healthy individuals, and the approach to determine wellness of individuals is multifaceted. Blood gas analysis serves as a useful adjunctive diagnostic test for health assessment, but it is uncommonly applied to terrestrial reptiles. This study established reference intervals for venous blood gas panels in free-living eastern box turtles (, = 102) from Illinois and Tennessee, and modeled the effects of environmental and physiologic parameters on each blood gas analyte. Blood gas panels included pH, partial pressure of oxygen (pO), partial pressure of carbon dioxide (pCO), total carbon dioxide (TCO), bicarbonate (HCO), base excess (BE) and lactate. Candidate sets of general linear models were constructed for each blood gas analyte and ranked using an information-theoretic approach (AIC). Season, packed cell volume (PCV) and activity level were the most important predictors for all blood gas analytes ( < 0.05). Elevations in PCV were associated with increases in pCO and lactate, and decreases in pH, pO, HCO, TCO and BE. Turtles with quiet activity levels had lower pH and pO and higher pCO than bright individuals. pH, HCO, TCO and BE were lowest in the summer, while pCO and lactate were highest. Overall, blood pH was most acidic in quiet turtles with elevated PCVs during summer. Trends in the respiratory and metabolic components of the blood gas panel tended to be synergistic rather than antagonistic, demonstrating that either (1) mixed acid-base disturbances are common or (2) chelonian blood pH can reach extreme values prior to activation of compensatory mechanisms. This study shows that box turtle blood gas analytes depend on several physiologic and environmental parameters and the results serve as a baseline for future evaluation.
可持续的野生动物种群依赖于健康的个体，而确定个体健康状况的方法是多方面的。血气分析作为健康评估的一种有用的辅助诊断测试，但在陆生爬行动物中应用并不常见。本研究建立了来自伊利诺伊州和田纳西州的自由生活的东部箱龟（n = 102）静脉血气指标的参考区间，并模拟了环境和生理参数对每种血气分析物的影响。血气指标包括pH值、氧分压（pO₂）、二氧化碳分压（pCO₂）、总二氧化碳（TCO₂）、碳酸氢盐（HCO₃⁻）、碱剩余（BE）和乳酸。针对每种血气分析物构建了一般线性模型的候选集，并使用信息论方法（AIC）进行排序。季节、红细胞压积（PCV）和活动水平是所有血气分析物最重要的预测因子（P < 0.05）。PCV升高与pCO₂和乳酸增加以及pH值、pO₂、HCO₃⁻、TCO₂和BE降低有关。活动水平安静的龟比活跃的龟pH值和pO₂更低，pCO₂更高。pH值、HCO₃⁻、TCO₂和BE在夏季最低，而pCO₂和乳酸最高。总体而言，夏季PCV升高且活动安静的龟的血液pH值最酸。血气指标中呼吸和代谢成分的趋势往往是协同的而非拮抗的，这表明要么（1）混合性酸碱紊乱很常见，要么（2）龟类血液pH值在补偿机制激活之前可以达到极值。本研究表明箱龟的血气分析物取决于几个生理和环境参数，其结果可作为未来评估的基线。
