Anal oxygen administration may save lives

FISH BREATHE through their gills. But some also breathe through their bottoms. Vertebrate guts are abundantly supplied with blood vessels, to enable them to absorb digested food. That means they can, in principle, absorb oxygen, too. And this is precisely what happens in species such as the weather loach (pictured).As far as is known, no land vertebrate can perform this trick. But, in a paper just published in , Takebe Takanori of the Cincinnati Children’s Hospital, in Ohio, describes how terrestrial animals might, with a bit of assistance, be enabled to do so. So far, Dr Takebe and his colleagues have turned mice, rats and pigs into bottom-breathers. If they can extend the trick to people, it could offer an alternative to tracheal intubation as a means of keeping those with breathing difficulties alive.