News / Science & Technology

Genetically-Modified Rainbow Trout Could Boost Aquaculture

Comparing a standard grown rainbow trout (left) and a genetically-modified rainbow trout (right). Both fish are the same age.
Comparing a standard grown rainbow trout (left) and a genetically-modified rainbow trout (right). Both fish are the same age.

For many years millions of people around the world have been fed by genetically-modified crops.  Soon, some food animals will be genetically-modified as well, to be larger and grow more efficiently to feed a rapidly growing population.  
At a laboratory in Rhode Island, rainbow trout much larger than usual are already being produced.

The two rainbow trout (pictured above) are the same age and were raised in the same tank.  But the larger one has been genetically modified. 

"You can see this enhanced muscling and these are the parent stock,"  Professor Terry Bradley explained. Bradley leads the research at [the Department of fisheries and veterinary science at] the University of Rhode Island. "The other fish on the bottom, you can see it doesn't have the increased muscle mass.  So we know this fish has about 20 percent more muscle mass than the standard fish has."

The process starts in a laboratory.  Over the last four years, Dr. Bradley has injected 20,000 rainbow trout eggs with a DNA variation which inhibits a protein that restricts muscle growth.

"Each egg and the micro pump is set to deliver 5 nano-liters of DNA which you cannot see it.  We put dye in it, so all you see is this tiny little dot inside the egg, of green food coloring, and that's the only way you know it has been injected," he said.

In a normal-sized trout, a genetically-controlled protein called "Myostatin" keeps the fish from growing beyond a certain size.

Dr. Bradley's research shows that altering the gene that produces Myostatin seems to result in more muscle mass

"We inject them into the egg, so each egg gets injected with a little bit of DNA," he says, "and if you get lucky a bit of that gets incorporated into the genome of the developing embryo and that develops into a fish."

Once the eggs hatch they start their journey through a series of tanks in this aquaculture research facility.  But from all the thousands of injected eggs, only 300 fish so far have carried the modified gene.

The research will continue for a few more years before a larger and more efficiently-growing rainbow trout can move on to the commercial markets.  Bradley says the final goal is to increase the overall efficiency of aquaculture.

"For example where it typically may take 1.2 kilogram of feed to produce one kilogram of fish we hope that by inhibiting Myostatin we hope that one kilogram of food will produce one kilogram of fish," Bradley said.

Professor Bradley's study has been funded by the U.S. Department of Agriculture.  

"The purpose of understanding muscle growth would be, first, to produce that muscle in a more efficient and more sustainable manner, that is to produce more meet for consumption with less input of resources, less energy, less feed, less labor input," stated Mark Mirando, who is with the Department's National Institute of Food and Agriculture. 

And perhaps, he says, with better taste or more nutrients. Worldwide, the fish most commonly produced through aquaculture are catfish and tilapia, both freshwater species.  But salmonid species like salmon and trout are rapidly becoming more popular in the industry.

The U.S. Department of Agriculture says the value of aquaculture production rose to nearly $1 billion in the U.S.over the past 20 years, mostly due to growing demand for fish in general and harvesting restrictions on wild fish.
Mirando says the rapid growth of aquaculture is linked to population growth.

"The demand for seafood in the U.S. and worldwide is rapidly increasing but the ability of the oceans to supply that food, even at the current levels, disregarding population increases and increases in demand; the ability of the oceans to supply that is diminishing," Mirando said.

Mirando dismisses concerns about genetic modifications, pointing out that humans have already genetically modified many plants and animals through centuries of selective breeding.  The most common examples, he says, are dogs, which range in size from Chihuahuas to great Danes.

Comparing a standard grown rainbow trout (left) and a genetically-modified rainbow trout (right). Both fish are the same age.

You May Like

Could Nemtsov Threaten Putin in Death as in Life?

Dynamic and debonair opposition leader had supported liberal economic reforms, criticized Russian president's aggression in Ukraine More

Oil Smuggling Highlights Challenges in Shutting Down IS Finances

Pentagon spokesman says Islamic State 'certainly continues to get revenue from the oil industry black market' but that airstrikes have made a dent More

India Focuses on Infrastructure, Investment to Propel Economy

Government expects economy to grow at 8 to 8.5 percent in next fiscal year More

This forum has been closed.
Comments
     
There are no comments in this forum. Be first and add one

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
US Supreme Court Hears Hijab Discrimination Casei
X
Katherine Gypson
February 25, 2015 11:30 PM
The U.S. Supreme Court has heard opening arguments in a workplace religious discrimination case that examines whether a clothing store can refuse to hire a young woman for wearing the headscarf she says is a symbol of her Muslim faith. Katherine Gypson reports from the Supreme Court.
Video

Video US Supreme Court Hears Hijab Discrimination Case

The U.S. Supreme Court has heard opening arguments in a workplace religious discrimination case that examines whether a clothing store can refuse to hire a young woman for wearing the headscarf she says is a symbol of her Muslim faith. Katherine Gypson reports from the Supreme Court.
Video

Video Falling Gas Prices Hurt Nascent Illinois Hydraulic Fracturing Industry

Falling oil prices are helping consumers purchase cheaper petroleum at the pump. But that’s made hydraulic fracturing or “fracking” less economically viable for the companies in the United States invested in the process. VOA’s Kane Farabaugh reports on one Midwestern town that was hoping to change its fortunes by cashing in on the next big U.S. oil boom.
Video

Video Fighting in Sudan's South Kordofan Fuels Mass Displacement

Heavy fighting in Sudan's South Kordofan state is causing hundreds of thousands to flee into uncertain conditions. Local aid organizations estimate as many as 400,000 civilians have been internally displaced since the conflict began more than three years ago, while another 250,000 have fled across the border to refugee camps in South Sudan. VOA's Adam Bailes reports.
Video

Video Lao Dam Project Runs Into Opposition

A Lao dam project on a section of the Mekong River is drawing opposition from local fishermen, international environmental groups and neighboring countries. VOA's Say Mony visited the region to investigate the concerns. Colin Lovett narrates.
Video

Video A Filmmaker Discovers Her Biracial Identity in "Little White Lie

Lacey Schwartz grew up in an upper middle-class Jewish family, in a town in upstate New York where almost everyone she knew was white. She assumed that she was, as well. Her recent documentary, Little White Lie, tells the story of how she uncovered the secret of her true racial background. VOA’s Carolyn Weaver has more on the film.
Video

Video Deep Under Antarctic Ice Sheet, Life!

With the end of summer in the Southern hemisphere, the Antarctic research season is over. Scientists from Northern Illinois University are back in their laboratory after a 3-month expedition on the Ross Ice Shelf, the world’s largest floating ice sheet. As VOA’s Rosanne Skirble reports, they hope to find clues to explain the dynamics of the rapidly melting ice and its impact on sea level rise.
Video

Video US-Cuba Normalization Talks Resume Friday

Negotiations aimed at normalizing diplomatic relations between the U.S. and Cuba resume Friday. On the table: lifting a half-century trade embargo and easing banking and travel restrictions. There's opposition in Congress, but some analysts say there may be sufficient political and economic incentives in both nations for a potential breakthrough this year. VOA's Mil Arcega reports.
Video

Video Pakistan's Deadline For SIM Registration Has Cellphone Users Scrambling

Pakistani cell phone users have until midnight Thursday to register their SIM cards, or their service will be cut off. While some privacy experts worry about government intrusion, many Pakistanis are just worried about keeping their phone lines open. VOA Deewa reporter Arshad Muhmand has more from Peshawar.
Video

Video Myanmar Warns Factory Workers to End Strikes

Outside Myanmar's main city Yangon, thousands of workers walked off their jobs earlier this month demanding a doubling of their wages, pay raises after a year and input from labor unions on industrial regulations. Since Friday, the standoff has grown more tense as police moved in to disrupt the sit-ins, resulting in clashes that injured people from both sides. VOA correspondent Steve Herman visited industrial zones which have become a focus of Myanmar's fledgling workers rights movement.
Video

Video Oscar Winners Do More Than Thank the Academy

The Academy Awards presentation is Hollywood’s night to reward the best movies from the previous year. It’s typically a lot of glitter, a lot of thank you’s, a lot of speeches. But many of this year’s speeches carried messages beyond the thank you's. VOA’s Carolyn Presutti takes a look.

All About America

Circumventing Censorship

An Internet Primer for Healthy Web Habits

As surveillance and censoring technologies advance, so, too, do new tools for your computer or mobile device that help protect your privacy and break through Internet censorship.
More