Video | Business Headlines | Internet | Science | Scientific Ethics | Technology | Search

 


Fish experience heart failure as water temperature rises

Fish experience heart failure as water temperature rises

Fish may experience heart failure as ocean temperatures rise due to climate change, according to new research from the University of Auckland.

School of Biological Sciences researchers Anthony Hickey and Fathima Iftikar say the effect of climate change on animals is clear, particularly ectotherms, or cold-bodied animals, such as most fish which rely on their surroundings to maintain optimum body temperature.

“This research shows that the heart acts as a ‘bio-indicator’ of which species may survive rises in ocean temperature but exactly why heart failure occurs we still don’t know,” Dr Hickey says.

The new study, funded through the Marsden Fund and involving Canadian and Australian researchers, found that mitochondria – the power units within heart cells – begin to fail as temperatures rise.

Dr Hickey and Dr Iftikar exposed three species of wrasse from different environments – tropical, temperate and cold – to gradually rising water temperatures. The Australian tropical species Thalassoma lunare (commonly known as moon wrasse) fared worst. These fish inhabit the narrowest thermal range of any species in the study.

“The tropical wrasse could only tolerate a shift of a few degrees before experiencing changes to their mitochondria, and this resulted in a loss of efficiency so that even though the fish could acclimatise to some degree, it came at a cost,” Dr Hickey says.

The life-sustaining mitochondria began to fail in all three species before full heart failure occurred, suggesting mitochondrial failure likely accounts for heart failure in heat-stressed animals.

The study suggests that the impact of changes in temperature have an impact on fish mitochondria, limiting the range of environments the fish can occupy. This has important implications if sea temperature rises predicted by climate scientists are accurate, Dr Hickey says.

“Understanding mitochondrial function, or dysfunction, in ectotherms such as fish has important ramifications in terms of climate change and requires more study to investigate the capacity of a wide range of species to survive ocean warming.”

Similar responses have been seen in commercially-important crab species, and in heat stressed mammalian mitochondria.

ENDS

© Scoop Media

 
 
 
 
 
Business Headlines | Sci-Tech Headlines

 

NZX Review: Best Practice Code Recommends Code Of Ethics

NZX, the sharemarket operator, is seeking feedback on proposed changes to its corporate governance best practice code including a published code of ethics, rules about share trading and continuous disclosure, and more transparency over board appointments and chief executive pay. More>>

ALSO:

Auditors:

Signs Of Life? SETI On Russian Space(?) Signal

A star system 94 light-years away is in the spotlight as a possible candidate for intelligent inhabitants, thanks to the discovery of a radio signal by a group of Russian astronomers... Could it be a transmission from a technically proficient society? At this point, we can only consider what is known so far. More>>

Post-Post: Brian Roche To Step Down As NZ Post CEO

Brian Roche will step down as chief executive of New Zealand Post in April 2017, having led the state-owned postal service's drive to adjust to shrinking mail volumes with a combination of cost cuts, asset sales, modernisation and expansion of new businesses. More>>

ALSO:

Company Results: Air NZ Rides The Tourism Boom With Record Full-Year Earnings

Air New Zealand has ridden the tourism boom and staved off increased competition to deliver the best full-year earnings in its 76-year history. More>>

ALSO:

New PGP: Sheep Milk Industry Gets $12.6M Crown Funding

The Sheep - Horizon Three programme aims to develop "a market driven, end-to-end value chain generating annual revenues of between $200 million and $700 million by 2030," according to a joint statement. More>>

ALSO:

Half Full: Fonterra Raises Forecast Milk Price

Fonterra Co-operative Group Limited today increased its 2016/17 forecast Farmgate Milk Price by 50 cents to $4.75 per kgMS. When combined with the forecast earnings per share range for the 2017 financial year of 50 to 60 cents, the total payout available to farmers in the current season is forecast to be $5.25 to $5.35 before retentions. More>>

ALSO:

Get More From Scoop

 
 
 
 
 
 
 
 
 
Sci-Tech
Search Scoop  
 
 
Powered by Vodafone
NZ independent news