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

 

Back Again: Government Approves TPP11 Mandate

Trade Minister Todd McClay says New Zealand will be pushing for the minimal number of changes possible to the original TPP agreement, something that the remaining TPP11 countries have agreed on. More>>

ALSO:

By May 2018: Wider, Earlier Microbead Ban

The sale and manufacture of wash-off products containing plastic microbeads will be banned in New Zealand earlier than previously expected, Associate Environment Minister Scott Simpson announced today. More>>

ALSO:

Snail-ier Mail: NZ Post To Ditch FastPost

New Zealand Post customers will see a change to how they can send priority mail from 1 January 2018. The FastPost service will no longer be available from this date. More>>

ALSO:

Property Institute: English Backs Of Debt To Income Plan

Property Institute of New Zealand Chief Executive Ashley Church is applauding today’s decision, by Prime Minister Bill English, to take Debt-to-income ratios off the table as a tool available to the Reserve Bank. More>>

ALSO:

Divesting: NZ Super Fund Shifts Passive Equities To Low-Carbon

The NZ$35 billion NZ Super Fund’s NZ$14 billion global passive equity portfolio, 40% of the overall Fund, is now low-carbon, the Guardians of New Zealand Superannuation announced today. More>>

ALSO: