Carp Fish Live Without Breathing

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Doctor's Orders Brewing
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Cool, carp fish can live without breathing by converting lactic acid to ethanol (alcohol).


Secret of oxygen-deprived fish may help humans
Canadian Press

VANCOUVER Champagne bubbled at the University of B.C.'s zoology lab as scientists celebrated the discovery of a secret trick used by fish to live without breathing.

Scientists and anglers have long known the crucian carp, which lives under ice-and snow-covered ponds in Scandinavia, had a special respiratory system.

It can live up to four months without oxygen. UBC researcher Jonathan Stecyk has been feted in the October issue of the journal Science for his study into how the fish pulls it off, which could have implications for people.

"Maybe one day we'll be able to make a human heart work the same way," he said.

"If you think about heart transplants, you only have a couple hours to transplant the heart from the donor to the recipient. If you could somehow extend that time period, you'd have more hearts to give to people who need them.
"Hopefully people will see this research and be inspired to exploit the abilities of this fish," he said.

Stecyk was so intrigued by the carp, he went to Norway and climbed into a fishing boat. For three weeks, he scooped the fish nets and studied the fish.

He wanted to see how the carp's heart worked when it wasn't breathing and discovered that it could maintain normal levels of cardiac activity without oxygen. Its brain also continued to send control messages to the heart that kept it pumping.

He is the first scientist to report such a finding in a vertebrate.

"Most (vertebrates) die within a minute, others show strongly suppressed cardiac activity," he said.

He believes the carp is able to carry on normal cardiac pumping without oxygen by ridding itself of lactic acid - the stuff that produces a burning sensation in human muscles after exercise - by converting it to ethanol, an alcohol, which is much less harmful.

A regular heartbeat may ensure that ethanol is circulated to the gills, where it is excreted to the surrounding water.
"Otherwise you'd have an intoxicated fish," he said.

Much like some in the lab who celebrated the printing of Stecyk's work in Science.

Stecyk is optimistic the recognition will hook more carp research dollars and more discoveries, though the Canadian government has already been quite supportive.

"So far it hasn't been hard. I'm only 26 and I've been to Europe six times to do studies and I've never had to pay.

"It's great, you meet so many different people and learn all these new ways of looking at scientific problems," said Stecyk, a PhD candidate in UBC's zoology department.

He is preparing to return to Norway in late October to test his guess that the carp is able to maintain normal cardiac activity by converting lactic acid to ethanol and excreting it.

The Duke

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thanks Doc!
i find stuff like this really interesting ... I would be all for a whole formum dedicated to brewscience.
one thing that i am trying to work out is how an insulated wort's temperature flucuates in relation to it's volume... ie. to what extent to you need to insulate to ensure the right temperature is maintained? If there was a formula where you just plugged in the room temperature, volume of brew, type of yeast, ....... magic. I don't have a heat pad/belt/submersion heater and I don't want to use them.


Bobby Dazzler Brewery
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that would be difficult as it would have to factor in levels of oxygenation, yeast viability and health and other things....

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