Featured Research

from universities, journals, and other organizations

New insight into physiology of salmon's intestines

Date:
December 3, 2013
Source:
Norwegian School of Veterinary Science
Summary:
A PhD research project has provided essential knowledge about the mechanisms leading to feed-induced enteritis in salmon and also insight into the salmon's intestinal immune defense system. This research provides a good foundation for developing new types of salmon feed, which must be based on new ingredients.

A PhD research project at the Norwegian School of Veterinary Science has provided essential knowledge about the mechanisms leading to feed-induced enteritis in salmon and also insight into the salmon's intestinal immune defense system. This research provides a good foundation for developing new types of salmon feed, which must be based on new ingredients.

Norwegian salmon farming has experienced an extremely high growth rate since its small beginnings in 1970 and the industry seems to be still growing. Fundamental and targeted research has always been an important prerequisite for this growth. Nevertheless, we still do not know enough about a number of fundamental, biological factors that are essential for achieving continued growth in the industry and for safeguarding fish welfare. One example is a lack of basic understanding about the physiology of the salmon's digestive system in the early stages of life. Furthermore, we know little about the long-term consequences for the development and health of salmon when feed based on marine ingredients is replaced by alternative feed sources -- an issue that profoundly affects future growth in the industry.

For the first time, Christian Sahlmann's doctoral thesis describes in detail the development and functions of salmon fry's gastrointestinal tract. Sahlmann's findings indicate that salmon is capable of digesting feed and absorbing nutrients approximately one week before the yolk sac is absorbed. It may therefore be appropriate to consider whether the feeding of salmon in hatcheries should start a week earlier than is commonly the practice today. Sahlmann's findings provide a starting point for further research into how to give the fish the best possible start in life.

The increased use of plant materials results in many cases to less growth and presents a hazard to the digestive health of many fish species, including salmon. Salmon living in seawater and given feed containing soy and certain other pulses, such as peas, develop a serious inflammation of the distal (posterior) intestine. Sahlmann found that during the first months of life, salmon do not suffer from inflammations of this kind. This indicates that the immune defence system in the intestines of salmon fry is less sensitive and therefore more able to tolerate variations in the composition of feed than during later life. This discovery provides a new premise for developing feed which will ensure optimal growth and welfare in salmon when feeding commences and perhaps also later in life.

The digestive system of smolt can react very rapidly to changes in feed Sahlmann's studies are the first to show how the distal intestine in salmon at the smolt stage is affected in the earliest stages following a change in feed from one based on fishmeal to one containing a large proportion of soybean meal. Only 24 hours after such a change in feed, changes could be seen in both gene expression and protein expression and on a functional level. This research presents us with fundamental knowledge about the mechanisms leading to feed-induced inflammation in salmon in particular, and increased insight into the intestinal immune defence system in general. Further, it provides a stronger platform for developing types of feed which must be based on new ingredients and points out relevant indicators for good intestinal health.


Story Source:

The above story is based on materials provided by Norwegian School of Veterinary Science. Note: Materials may be edited for content and length.


Cite This Page:

Norwegian School of Veterinary Science. "New insight into physiology of salmon's intestines." ScienceDaily. ScienceDaily, 3 December 2013. <www.sciencedaily.com/releases/2013/12/131203090706.htm>.
Norwegian School of Veterinary Science. (2013, December 3). New insight into physiology of salmon's intestines. ScienceDaily. Retrieved September 18, 2014 from www.sciencedaily.com/releases/2013/12/131203090706.htm
Norwegian School of Veterinary Science. "New insight into physiology of salmon's intestines." ScienceDaily. www.sciencedaily.com/releases/2013/12/131203090706.htm (accessed September 18, 2014).

Share This



More Plants & Animals News

Thursday, September 18, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Chimp Violence Study Renews Debate On Why They Kill

Chimp Violence Study Renews Debate On Why They Kill

Newsy (Sep. 17, 2014) The study weighs in on a debate over whether chimps are naturally violent or become that way due to human interference in the environment. Video provided by Newsy
Powered by NewsLook.com
Some Tobacco Farmers Thrive Amid Challenges

Some Tobacco Farmers Thrive Amid Challenges

AP (Sep. 16, 2014) The South's tobacco country is surviving, and even thriving in some cases, as demand overseas keeps growers in the fields of one of America's oldest cash crops. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Scientists Given Rare Glimpse of 350-Kilo Colossal Squid

Scientists Given Rare Glimpse of 350-Kilo Colossal Squid

AFP (Sep. 16, 2014) Scientists say a female colossal squid weighing an estimated 350 kilograms (770 lbs) and thought to be only the second intact specimen ever found was carrying eggs when discovered in the Antarctic. Duration: 00:47 Video provided by AFP
Powered by NewsLook.com
Raw: Scientists Examine Colossal Squid

Raw: Scientists Examine Colossal Squid

AP (Sep. 16, 2014) Squid experts in New Zealand thawed and examined an unusual catch on Tuesday: a colossal squid. It was captured in Antarctica's remote Ross Sea in December last year and has been frozen for eight months. (Sept. 16) Video provided by AP
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:
from the past week

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