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

Video British Fighters on Frontline of Islamic State Information War

It’s estimated that several hundred British citizens are fighting for Islamic State alongside other foreign jihadists More

Pakistan's Political Turmoil Again Shines Spotlight on Military

Thousands of protesters calling for PM Sharif to step down continue protests in front of parliament, as critics fear political impasse could spur another military coup More

Photogallery Ebola Quarantines Spark Anxiety in Liberian Capital

Food prices rise sharply as residents attempting purchases clash with security forces, leaving one person dead 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.
Native Bees May Help Save Cropsi
X
Deborah Block
August 22, 2014 12:23 AM
U.S. President Barack Obama has called for a federal strategy to promote the health of bees that have been declining. The honeybee has been waning due to parasites, disease and pesticides. Wild bees may be used to take over their role as crop pollinators. Scientists first need to learn a lot more about wild bees, says biologist Sam Droege, who is pioneering the first national inventory on native bees. VOA’s Deborah Block went to his research laboratory in Beltsville, Maryland, to bring you more.
Video

Video Native Bees May Help Save Crops

U.S. President Barack Obama has called for a federal strategy to promote the health of bees that have been declining. The honeybee has been waning due to parasites, disease and pesticides. Wild bees may be used to take over their role as crop pollinators. Scientists first need to learn a lot more about wild bees, says biologist Sam Droege, who is pioneering the first national inventory on native bees. VOA’s Deborah Block went to his research laboratory in Beltsville, Maryland, to bring you more.
Video

Video US Defense Officials Plan for Long-Term Strategy to Contain Islamic State

U.S. defense officials say American air strikes in Iraq have helped deter Islamic State militants for the time being, but that a broad international effort is needed to defeat the extremists permanently. Defense Secretary Chuck Hagel warned Thursday that the group formerly known as the Islamic State in Iraq and the Levant, or ISIL, is better organized, and financially and militarily stronger than any other known terrorist group. Zlatica Hoke has more.
Video

Video Drug-Resistant Malaria Spreads in Southeast Asia

On Thailand’s border with Myanmar, also known as Burma, a malaria research and treatment clinic is stepping up efforts to eliminate a drug-resistant form of the parasite - before it spreads abroad. Steve Sandford reports from Mae Sot, Thailand.
Video

Video Gaza Conflict, Hamas Popularity Challenge Abbas

The Palestinian unity government of Mahmoud Abbas has failed to convince Hamas to agree to Egyptian-negotiated terms with Israel on a Gaza cease-fire. VOA State Department Correspondent Scott Stearns reports on what the Gaza conflict means for President Abbas, with whom U.S. officials have worked for years on a two-state solution to the Israeli-Palestinian conflict.
Video

Video Nigeria's 'Nollywood' Movie Industry Rolls in High Gear

Twenty years after its birth in a video shop in Lagos, Nigeria's "Nollywood" is one of the most prolific film industries on earth. Despite low budgets and whirlwind production schedules, Nigerian films are wildly popular in Africa and industry professionals say they hope, in the future, their films will be as great in quality as they are in quantity. Heather Murdock has more for VOA from Lagos.
Video

Video UN Launches 'Biggest Aid Operation in 30 Years' in Iraq

The United Nations has launched what it describes as one of the biggest aid operations in 30 years in northern Iraq, as hundreds of thousands of refugees flee the extremist Sunni militant group calling itself the Islamic State. As Kurdish and Iraqi forces battle the Sunni insurgents, the fighting has forced more people to flee their homes. Kurdish authorities say the international community must act now to avert a humanitarian catastrophe. Henry Ridgwell reports for VOA from London.
Video

Video Cambodian American Hip Hop Artist Sings of Personal Struggles

A growing underground movement of Cambodian American hip hop artists is rapping about the struggles of living in urban America. Most, if not all of them, are refugees or children of refugees who came to the United States from Cambodia to escape the Khmer Rouge genocide of the 1970s. Through their music, the artists hope to give voice to immigrants who have been struggling quietly for years. Elizabeth Lee reports from Long Beach, California.
Video

Video African Media Tries to Educate Public About Ebola

While the Ebola epidemic continues to claim lives in West Africa, information technology specialists, together with radio and TV reporters, are battling misinformation and prejudice about the disease - using social media to educate the public about the deadly virus. VOA’s George Putic has more.

AppleAndroid