Featured Research

from universities, journals, and other organizations

Improving salmon's success in the wild and aquaculture

Date:
September 23, 2013
Source:
Uni Research
Summary:
Have you ever been stressed and forgot what you were doing? Chronic mild stress may explain why many salmon don´t return to our rivers and why 20% of salmon production is lost every year.

Smolt in the laboratory.
Credit: Image courtesy of Uni Research

Have you ever been stressed and forgot what you were doing? Chronic mild stress may explain why many salmon don´t return to our rivers and why 20% of salmon production is lost every year.

Related Articles


Chronic mild stressors, such as a bad working environment, marital problems or sleepless nights with small children, are well known to cause learning and memory problems.

Researchers at Uni Research AS have shown that the same is true for salmon. This type of stress is very difficult to detect by traditional means. Often not until it is too late! Whether salmon are transferred from rearing tanks to sea-cages in aquaculture or are migrating from freshwater to the sea, their ability to learn and adapt rapidly to the new environments will dictate their future success.

The research team in the Integrative Fish Biology group at Uni Research AS has been establishing new ways to evaluate the salmon´s mental robustness, the ability to react and learn quickly in a new environment, before its too late. They recently showed that salmon exposed to poor water quality were poorer learners and that markers in the brain can show the fish have experienced chronic mild stress (Grassie et al 2013).

Identifying environmental situations that cause chronic mild stress will improve fish welfare and reduce losses in fish aquaculture. In addition, these researchers have shown that the same tools can be applied to improve the restoration of our salmon populations. A recent article by Ebbesson and co-workers in The Proceedings of the Royal Society, shows that raising fish in an environment with "furniture" improves their learning ability (Salvanes et al 2013).

These data demonstrate that alternative rearing strategies for restoration fish need to be found. These types of studies will provide new welfare indicators for the evaluation of welfare and aid in determining stress thresholds that can provide an optimal welfare and improved production. Together these physiological and mental robustness indicators will provide important information in the evaluation of the fishes robustness towards future challenges.

Fish welfare

Previously, a homeostatic-based definition of welfare postulated a negative linear relationship between stress and welfare, stability and no threats to homeostasis means the best welfare. In recent years, a new concept of welfare based on allostasis suggests an inverted U-shaped relationship, where both too little or too much stress gives poor welfare (Korte et al., 2007).

The allostasis concept is an important model to discriminate between normal adaptive stress responses and situations leading to poor animal welfare. Good animal welfare is characterized by a broad predictive physiological, cognitive, and behavioural capacity to anticipate and respond to environmental challenges in a way that matches the environmental demands (McEwen and Wingfield 2003, 2010).

Reducing these capacities leads to a mismatch between the response required by the actual conditions and the actual responses activated by animal, limiting the ability to experience good welfare. Understanding how the mediators of allostasis and coping ability are affected by stress level will give us a better understanding about the regulation of fish welfare.

Recent studies in fish have demonstrated that previous environmental experiences, whether negative (Grassie et al 2013) or positive (Salvanes et al 2013) provide learning and memory-based mechanisms to efficiently deal with environmental challenges, integrating physiological stress and cognitive abilities (Ebbesson et al 2013).


Story Source:

The above story is based on materials provided by Uni Research. Note: Materials may be edited for content and length.


Journal Reference:

  1. A. G. V. Salvanes, O. Moberg, L. O. E. Ebbesson, T. O. Nilsen, K. H. Jensen, V. A. Braithwaite. Environmental enrichment promotes neural plasticity and cognitive ability in fish. Proceedings of the Royal Society B: Biological Sciences, 2013; 280 (1767): 20131331 DOI: 10.1098/rspb.2013.1331

Cite This Page:

Uni Research. "Improving salmon's success in the wild and aquaculture." ScienceDaily. ScienceDaily, 23 September 2013. <www.sciencedaily.com/releases/2013/09/130923092941.htm>.
Uni Research. (2013, September 23). Improving salmon's success in the wild and aquaculture. ScienceDaily. Retrieved March 5, 2015 from www.sciencedaily.com/releases/2013/09/130923092941.htm
Uni Research. "Improving salmon's success in the wild and aquaculture." ScienceDaily. www.sciencedaily.com/releases/2013/09/130923092941.htm (accessed March 5, 2015).

Share This


More From ScienceDaily



More Plants & Animals News

Thursday, March 5, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Tourists Visit Rare Grey Whales in Mexico

Raw: Tourists Visit Rare Grey Whales in Mexico

AP (Mar. 4, 2015) — Once nearly extinct, grey whales now migrate in their thousands to Mexico&apos;s Vizcaino reserve in Baja California, in search of warmer waters to mate and give birth. Tourists flock to the reserve to see the whales, measuring up to 49 feet long. (March 4) Video provided by AP
Powered by NewsLook.com
Australian Museum Shares Terrifying Goblin Shark With the World

Australian Museum Shares Terrifying Goblin Shark With the World

Buzz60 (Mar. 4, 2015) — The Australian Museum has taken in its fourth-ever goblin shark, a rare fish with an electricity-sensing snout and &apos;alien-like&apos; jaw. Mike Janela (@mikejanela) takes a look. Video provided by Buzz60
Powered by NewsLook.com
New Hormone Could Protect Against Diabetes And Weight Gain

New Hormone Could Protect Against Diabetes And Weight Gain

Newsy (Mar. 4, 2015) — A newly discovered hormone mimics the effects of exercise, protecting against diabetes and weight gain. Video provided by Newsy
Powered by NewsLook.com
Prince William Calls for Unified Effort Against Illegal Wildlife Trade

Prince William Calls for Unified Effort Against Illegal Wildlife Trade

Reuters - Entertainment Video Online (Mar. 4, 2015) — Britain&apos;s Prince William pledges to unite against illegal wildlife trade on the final day of his visit to China. Rough cut - no reporter narration Video provided by Reuters
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