Featured Research

from universities, journals, and other organizations

Antimicrobial resistance in fish pathogenic bacteria and other bacteria in aquatic environments

Date:
November 19, 2012
Source:
Norwegian School of Veterinary Science
Summary:
Little attention has been paid to the use of antibiotics in the aquaculture industry as one reason for the increase in bacteria resistant to antibiotics and the spread of such resistance to other bacteria. Since the antibiotics that are used in veterinary medicine and aquaculture belong to the same group of antibiotics as those used in medicines for humans, increased resistance to these medicines will be detrimental to public health.

Little attention has been paid to the use of antibiotics in the aquaculture industry as one reason for the increase in bacteria resistant to antibiotics and the spread of such resistance to other bacteria. Since the antibiotics that are used in veterinary medicine and aquaculture belong to the same group of antibiotics as those used in medicines for humans, increased resistance to these medicines will be detrimental to public health.

Related Articles


Syed Qaswar Ali Shah's doctoral research project has studied the genetic foundation for resistance to antibiotics in bacteria isolated from salmon fish in Norway. He collected quinolone-resistant isolates of the bacterium Flavobacterium psychrophilum from rainbow trout and equivalent isolates of Yersinia ruckeri from Atlantic salmon. These bacteria are the cause of bacterial coldwater disease in rainbow trout and redmouth disease in salmon respectively. Only a limited number of antibiotic agents are authorised for use in aquaculture. The development of resistance to quinolones must lead to restrictions in the use of this drug in the aquaculture industry, heightened focus on the prevention of infection and the development of a vaccine against Flavobacterium psychrophilum so that infection is avoided.

Syed Qaswar Ali Shah also studied bacteria isolates with a view to discovering genes as codes for resistance to different antibiotics used in veterinary medicine. The bacteria isolates were collected from freshwater carp aquafarms in Pakistan, from tilapia farms in Tanzania and from fish farms in Chile and Norway. A significant proportion of the isolates were found to be resistant to several different types of antibiotics. The isolates from freshwater farms were found to contain more resistant bacteria than those from the seawater farms. In addition, Shah discovered resistance to antibiotics in isolates from freshwater farms which had not used antibiotics as a method of treatment. This can be explained by integrated fish farming operations, whereby fertiliser from other farm animals was used as an important source of feed for the farmed fish.

There were more bacteria resistant to antibiotics in the seawater isolates from Chile than in the isolates from Norway. The higher occurrence in Chile may be explained by the excessive use of antibiotics in salmon farming there: approx. 840 grams of antibiotics per 1000 kg fish in 2008. In comparison, approx. 1 gram per 1000 kg of fish was used in Norway in the same year.

Antibiotics are given as a feed supplement in the aquaculture industry and as a result, the surrounding environment is directly exposed to these drugs. Remains of feed containing antibiotics and undigested antibiotics in fish faeces are deposited in the sediment of the fish farms. Since many of these antibiotic substances are broken down slowly, they contribute towards an accumulation of antibiotics in the environment surrounding the farms which can result in local bacteria selecting genes resistant to antibiotics.

The development of acquired resistance in aquatic bacteria can result in a reservoir of resistant bacteria which spread resistance by means of horizontal gene transfer. Many aquatic bacteria and bacteria pathogenic for humans belong to the same group, such as Aeromonas, Acinetobacter, Kluyvera, Vibrio and Yersinia and this makes it easier for the bacteria to transfer resistant genes to other bacteria in the group. The presence of identical factors in bacteria found in aquatic environments and in clinical pathogens is clear proof that resistant genes from bacteria in aquaculture have spread to human pathogens.

Since the spread of bacteria pays no heed to political decisions or geographical borders, the development of resistance to antibiotics poses a serious threat to public health. The main reservoir of genes resistant to antibiotics is thought to exist in aquatic environments, and fish pathogenic bacteria represent a possible intermediate stage in the transfer of resistance from aquatic environments to resistant bacteria on land.

Syed Qaswar Ali Shah defended his doctoral research on 16th November 2012 at the Norwegian School of Veterinary Science (NVH) with a thesis entitled "Antimicrobial resistance in fish pathogenic and aquatic environmental bacteria".


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. "Antimicrobial resistance in fish pathogenic bacteria and other bacteria in aquatic environments." ScienceDaily. ScienceDaily, 19 November 2012. <www.sciencedaily.com/releases/2012/11/121119104637.htm>.
Norwegian School of Veterinary Science. (2012, November 19). Antimicrobial resistance in fish pathogenic bacteria and other bacteria in aquatic environments. ScienceDaily. Retrieved December 22, 2014 from www.sciencedaily.com/releases/2012/11/121119104637.htm
Norwegian School of Veterinary Science. "Antimicrobial resistance in fish pathogenic bacteria and other bacteria in aquatic environments." ScienceDaily. www.sciencedaily.com/releases/2012/11/121119104637.htm (accessed December 22, 2014).

Share This


More From ScienceDaily



More Plants & Animals News

Monday, December 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Christmas Kissing Good for Health

Christmas Kissing Good for Health

Reuters - Innovations Video Online (Dec. 22, 2014) Scientists in Amsterdam say couples transfer tens of millions of microbes when they kiss, encouraging healthy exposure to bacteria. Suzannah Butcher reports. Video provided by Reuters
Powered by NewsLook.com
Brain-Dwelling Tapeworm Reveals Genetic Secrets

Brain-Dwelling Tapeworm Reveals Genetic Secrets

Reuters - Innovations Video Online (Dec. 22, 2014) Cambridge scientists have unravelled the genetic code of a rare tapeworm that lived inside a patient's brain for at least four year. Researchers hope it will present new opportunities to diagnose and treat this invasive parasite. Matthew Stock reports. Video provided by Reuters
Powered by NewsLook.com
New Fish Species Discovered, Setting Record for World's Deepest

New Fish Species Discovered, Setting Record for World's Deepest

Buzz60 (Dec. 22, 2014) A new species of fish is discovered living five miles beneath the ocean surface, making it the deepest living fish on earth. Jen Markham has the story. Video provided by Buzz60
Powered by NewsLook.com
Earthworms Provide Cancer-Fighting Bacteria

Earthworms Provide Cancer-Fighting Bacteria

Reuters - Innovations Video Online (Dec. 21, 2014) Polish scientists isolate bacteria from earthworm intestines which they say may be used in antibiotics and cancer treatments. Suzannah Butcher reports. 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