Cauture Fabien, Sterba-Boatwright Blair, Rocho-Levine Julie, Harms Craig, Miedler Stefan, Fahlman Andreas
Departamento de Investigación, Fundación Oceanogràfic de la Comunidad Valenciana, Valencia, Spain.
Department of Mathematics and Statistics, Texas A&M University-Corpus Christi, Corpus Christi, TX, United States.
Front Physiol. 2019 Feb 19;10:128. doi: 10.3389/fphys.2019.00128. eCollection 2019.
Man-made environmental change may have significant impact on apex predators, like marine mammals. Thus, it is important to assess the physiological boundaries for survival in these species, and assess how climate change may affect foraging efficiency and the limits for survival. In the current study, we investigated whether the respiratory sinus arrhythmia (RSA) could estimate tidal volume ( ) in resting bottlenose dolphins (). For this purpose, we measured respiratory flow and electrocardiogram (ECG) in five adult bottlenose dolphins at rest while breathing voluntarily. Initially, an exponential decay function, using three parameters (baseline heart rate, the change in heart rate following a breath, and an exponential decay constant) was used to describe the temporal change in instantaneous heart rate following a breath. The three descriptors, in addition to body mass, were used to develop a Generalized Additive Model (GAM) to predict the inspired tidal volume ( ). The GAM allowed us to predict with an average ( ± SD) overestimate of 3 ± 2%. A jackknife sensitivity analysis, where 4 of the five dolphins were used to fit the GAM and the 5th dolphin used to make predictions resulted in an average overestimate of 2 ± 10%. Future studies should be used to assess whether similar relationships exist in active animals, allowing to be studied in free-ranging animals provided that heart rate can be measured.
人为环境变化可能会对顶级掠食者，如海洋哺乳动物产生重大影响。因此，评估这些物种生存的生理界限，以及评估气候变化如何影响觅食效率和生存极限非常重要。在当前的研究中，我们调查了呼吸性窦性心律不齐（RSA）是否可以估计静息宽吻海豚的潮气量（ ）。为此，我们在五只成年宽吻海豚自愿呼吸时测量了它们休息时的呼吸流量和心电图（ECG）。最初，使用一个指数衰减函数，该函数包含三个参数（基线心率、一次呼吸后心率的变化以及一个指数衰减常数）来描述一次呼吸后瞬时心率的时间变化。除了体重外，这三个描述符还被用于建立一个广义相加模型（GAM）来预测吸入潮气量（ ）。该GAM使我们能够预测 ，平均（±标准差）高估3±2%。进行了留一法敏感性分析，即五只海豚中的四只用于拟合GAM，第五只海豚用于进行预测，结果平均高估2±10%。未来的研究应用于评估活跃动物中是否存在类似关系，以便在能够测量心率的情况下，对自由放养动物的 进行研究。
