Featured Research

from universities, journals, and other organizations

It pays to keep salmon fit: Salmon farmers could save big by exercising their fish more -- without overexerting them

Date:
September 5, 2012
Source:
Research Council of Norway, The
Summary:
Salmon farmers could save huge sums by exercising their fish more. Researchers in Norway have tested various swimming exercise regimes for three years on salmon fry. The findings indicate that proper exercise can improve smolt health enough to significantly reduce losses at sea.

The survival rate are higher among properly exercised fish than among inactive salmon.
Credit: Skretting

Salmon farmers could save huge sums by exercising their fish more. Researchers in Norway have tested various swimming exercise regimes for three years on salmon fry. The findings indicate that proper exercise can improve smolt health enough to significantly reduce losses at sea.

In the final 12 weeks before transferring to sea cages, smolts should be swimming 0.8 to 1.2 body lengths per second.

With proper exercise the smolts develop more numerous, larger heart muscle cells and a stronger immune system. The exercise regime also increases bone formation and vertebral mineralisation in smolt, making them less likely to develop deformities.

Only 80-85 per cent of salmon smolts transferred to sea cages in Norway survive to reach slaughter size. The loss of the remainder costs producers billions of kroner each year. Escapes, disease, and handling-related injuries are the top causes, and scientists attribute a large proportion to poor smolt quality.

Swimming exercise cuts losses

"There are many reasons for poor smolt quality, but most are related to intensive production methods," says Senior Scientist Harald Takle of the Norwegian Institute of Food, Fisheries and Aquaculture Research (Nofima AS).

Dr Takle headed a team of Norwegian and international researchers who tested various exercise regimes for three years on salmon fry, from 30-gram parr to 100-gram smolts. Most of the trials were conducted at Nofima's Sunndalsψra Research Station, with complete control of current speed and oxygen saturation and monitoring of feed intake. The findings indicate that proper exercise can improve smolt health enough to significantly reduce losses at sea.

"We have devised what we believe approaches the optimal exercise regime for smolts during their last 12 weeks before being transferred to sea cages," explains Dr Takle. "With this exercise the smolts develop more numerous, larger heart muscle cells and a stronger immune system. For example, the survival rate among properly exercised fish when challenged with the IPN (infectious pancreatic necrosis) virus is up to 15 per cent higher than among inactive salmon."

Healthiest workout for salmon

"In the final 12 weeks before transferring to sea cages, smolts should be swimming 0.8 to 1.2 body lengths per second," recommends Nofima's Harald Takle. (Photo: Torkild Marsdal Hanssen) The exercise regime also increases bone formation and vertebral mineralisation in smolt, making them less likely to develop deformities.

Developing the innate swimming capacity of salmon also benefits their overall health. Good swimmers are more disease-resistant and withstand intensive interval exercise better than poor swimmers, which exhibit stress reactions to the exercise. In the round hatchery tanks, the intensity of the smolts' workout sessions can be regulated by the speed and distribution of the water current.

"Our trials indicate that swimming at least 0.8 body lengths per second strengthens the salmon heart. The optimal exercise intensity for smolts in their final 12 weeks before transfer to the sea cage looks to be roughly 0.8 to 1.2 body lengths per second. Speeds faster than this can have a negative effect," adds Dr Takle," as can major changes in current speed."

Industry players very interested

According to Dr Takle, many hatcheries could implement exercise regimes using a few simple measures. For others, achieving the necessary control of water current in their tanks could prove difficult. He says industry players are showing a great deal of interest in his team's findings and have placed new orders this spring for exercise regimes, which Dr Takle intends to fill.

Project facts

Title: Preventive health measure by optimizing swimming exercise to counteract lifestyle diseases of Atlantic salmon

  • Project period: 2009-2012
  • Project manager: Harald Takle, Nofima AS
  • Partners: Norwegian Institute for Water Research (NIVA), NTNU Faculty of Medicine, University of Western Brittany, University of British Columbia, AVS Chile
  • Funding: The Research Council of Norway's HAVBRUK programme and the Norwegian Seafood Research Fund (FHF)

Story Source:

The above story is based on materials provided by Research Council of Norway, The. The original article was written by Torkil Marsdal Hanssen; translation by Darren McKellep/Carol B. Eckmann. Note: Materials may be edited for content and length.


Cite This Page:

Research Council of Norway, The. "It pays to keep salmon fit: Salmon farmers could save big by exercising their fish more -- without overexerting them." ScienceDaily. ScienceDaily, 5 September 2012. <www.sciencedaily.com/releases/2012/09/120905083908.htm>.
Research Council of Norway, The. (2012, September 5). It pays to keep salmon fit: Salmon farmers could save big by exercising their fish more -- without overexerting them. ScienceDaily. Retrieved October 21, 2014 from www.sciencedaily.com/releases/2012/09/120905083908.htm
Research Council of Norway, The. "It pays to keep salmon fit: Salmon farmers could save big by exercising their fish more -- without overexerting them." ScienceDaily. www.sciencedaily.com/releases/2012/09/120905083908.htm (accessed October 21, 2014).

Share This



More Plants & Animals News

Tuesday, October 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

'Cadaver Dog' Sniffs out Human Remains

'Cadaver Dog' Sniffs out Human Remains

AP (Oct. 21, 2014) — Where's a body buried? Buster's nose can often tell you. He's a cadaver dog, specially trained to find human remains and increasingly being used by law enforcement and accepted in courts. These dogs are helping solve even decades-old mysteries. (Oct. 21) Video provided by AP
Powered by NewsLook.com
White Lion Cubs Born in Belgrade Zoo

White Lion Cubs Born in Belgrade Zoo

AFP (Oct. 20, 2014) — Two white lion cubs, an extremely rare subspecies of the African lion, were recently born at Belgrade Zoo. They are being bottle fed by zoo keepers after they were rejected by their mother after birth. Duration: 00:42 Video provided by AFP
Powered by NewsLook.com
Traditional Farming Methods Gaining Ground in Mali

Traditional Farming Methods Gaining Ground in Mali

AFP (Oct. 20, 2014) — He is leading a one man agricultural revolution in Mali - Oumar Diatabe uses traditional farming methods to get the most out of his land and is teaching others across the country how to do the same. Duration: 01:44 Video provided by AFP
Powered by NewsLook.com
Goliath Spider Will Give You Nightmares

Goliath Spider Will Give You Nightmares

Buzz60 (Oct. 20, 2014) — An entomologist stumbled upon a South American Goliath Birdeater. With a name like that, you know it's a terrifying creepy crawler. Sean Dowling (@SeanDowlingTV) has the details. Video provided by Buzz60
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins