Department of Animal Environment and Health, Swedish University of Agricultural Sciences, Skara SE-532 23, Sweden.
Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg SE-405 30, Sweden.
J Exp Biol. 2018 Jul 16;221(Pt 14):jeb180703. doi: 10.1242/jeb.180703.
The fish gut is responsible for numerous potentially energetically costly processes, yet little is known about its metabolism. Here, we provide the first measurements of aerobic metabolism of the gut in a teleost fish by measuring gut blood flow, as well as arterial and portal venous oxygen content. At 10°C, gut oxygen uptake rate was 4.3±0.5 ml O h kg (∼11% of whole-animal oxygen uptake). Following acute warming to 15°C, gut blood flow increased ∼3.4-fold and gut oxygen uptake rate increased ∼3.7-fold (16.0±3.3 ml O h kg), now representing ∼25% of whole-animal oxygen uptake. Although gut blood flow decreased following an acute stress event at 15°C, gut oxygen uptake remained unchanged as a result of a ∼2-fold increase in oxygen extraction. The high metabolic thermal sensitivity of the gut could have important implications for the overall aerobic capacity and performance of fish in a warming world and warrants further investigation.
鱼的肠道负责许多潜在的高能量消耗过程，但对其代谢知之甚少。在这里，我们通过测量肠道血液流量以及动脉和门静脉的氧含量，首次测量了硬骨鱼肠道的有氧代谢。在 10°C 时，肠道耗氧量为 4.3±0.5 ml O h kg（约占整个动物耗氧量的 11%）。急性升温至 15°C 后，肠道血液流量增加了约 3.4 倍，肠道耗氧量增加了约 3.7 倍（16.0±3.3 ml O h kg），现占整个动物耗氧量的 25%左右。尽管在 15°C 的急性应激事件后肠道血液流量下降，但由于氧摄取量增加了约 2 倍，肠道耗氧量保持不变。肠道的高代谢热敏感性可能对鱼类在变暖世界中的整体有氧能力和表现有重要影响，值得进一步研究。
