We measured resting metabolic rate (RMR), tidal volume (V_T), breathing frequency (f_R), respiratory flow, and end-expired gases in rough-toothed dolphins (Steno bredanensis) housed in managed care after an overnight fast and 1–2 hr following a meal. The measured average (± standard deviation) V_T (4.0 ± 1.3 L) and f_R (1.9 ± 1.0 breaths/min) were higher and lower, respectively, as compared with estimated values from both terrestrial and aquatic mammals, and the average V_T was 43% of the estimated total lung capacity. The end-expired gas levels suggested that this species keep alveolar O₂ (10.6% or 80 mmHg) and CO₂ (7.6% or 57 mmHg), and likely arterial gas tensions, low and high, respectively, to maximize efficiency of gas exchange. We show that following an overnight fast, the RMR (566 ± 158 ml O₂/min) was 1.8 times the estimated value predicted by Kleiber for terrestrial mammals of the same size. We also show that between 1 and 2 hr after ingestion of a meal, the metabolic rate increases an average of 29% (709 ± 126 ml O₂/min). Both body mass (M_b) and f_R significantly altered the measured RMR and we propose that both these variables should be measured when estimating energy use in cetaceans.

中文翻译：

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禁食和喂食粗齿海豚（Steno bredanensis）的静息代谢率和肺功能

_{我们测量了在管理护理}中饲养的粗齿海豚 ( Steno bredanensis )的静息代谢率 (RMR)、潮气量 ( VT )、呼吸频率 ( fR ₎ 、呼吸流量和呼气末气体。 – 餐后 2 小时。与陆地和水生哺乳动物的估计值相比，测量的平均值（±标准偏差）V _T (4.0 ± 1.3 L) 和f _{R (1.9 ± 1.0 次呼吸/分钟) 分别较高和较低，并且平均}V _T为估计总肺活量的 43%。呼气末气体水平表明，该物种分别保持肺泡 O ₂（10.6% 或 80 mmHg）和 CO ₂（7.6% 或 57 mmHg）以及可能的动脉气体张力，以最大限度地提高气体交换效率。我们发现，禁食过夜后，RMR（566 ± 158 ml O ₂ /min）是 Kleiber 对相同体型的陆生哺乳动物预测的估计值的 1.8 倍。我们还表明，进食后 1 至 2 小时内，代谢率平均增加 29% (709 ± 126 ml O ₂ /min)。体重 ( M _b ) 和f _R都显着改变了测量的 RMR，我们建议在估计鲸类动物的能量消耗时应测量这两个变量。