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Green eggs and ham

Are genetically modified animals the solution to the environmental problem of a growing market for meat?


 
Green eggs and ham

Enviropig; University of Guelph

“When I look at the Enviropig,” says professor Richard Moccia, associate vice-president of research at the University of Guelph, “I’m in awe and amazement at the ability of humans to create this technology.” Though the pink mammals look, oink and act like regular Yorkshire pigs, they were created in a lab. In 1999, scientists at Guelph added an E. coli gene and mouse DNA to a normal pig embryo. The result: the “greener” Enviropig pig. Though no one has ever tasted an Enviropig, testing on its internal organs and meat cuts revealed it’s identical to a regular oinker. Except that this transgenic animal may solve an environmental problem, namely pollution caused by pig farming.

We know all about eating local foods, recycling and carpooling to reduce our environmental footprints. But how about opting for animal products genetically modified to be greener? A number of researchers in Canada and around the world are working at the frontiers of genetic modification to create animals—from pigs to trout—that they claim are less injurious to the environment.

The Enviropigs, for one, emit less phosphorus than normal pigs. Pigs need phosphorus in their diets, but it’s mostly indigestible for them; they lack the enzyme phytase. As a result, a lot of phosphorus ends up in their manure. Farmers, in turn, use pig manure as fertilizer, and when it rains, it trickles off farms and into bodies of water, where it promotes algae growth, strangling fish habitats by stealing oxygen and creating “dead zones.” Enviropigs have been modified to produce phytase so they excrete substantially less phosphorus. “It’s a low-pollution pig, if you will,” says Moccia.

A similar argument is being made for trout produced at the University of Rhode Island by Terry Bradley. The genetically modified fish contain inhibitors of the protein myostatin, which limits muscle growth. The result is a trout with more muscle mass than traditional fish. “You can equate these fish with Belgian Blue cattle, which use about 10 to 15 per cent less feed.” Like Belgian Blues, the cattle equivalent of a young Arnold Schwarzenegger, the trout grow to harvest size on a lot less food.

Bradley has not yet applied for U.S. FDA approval, but another GM fish creator did recently, to great hoopla. The Massachusetts-based biotechnology company AquaBounty’s “AquAdvantage” Atlantic salmon, deemed safe to eat by the FDA, grow faster than natural salmon (18 to 24 months as opposed to 30)—the result of receiving an extra growth hormone from Chinook salmon and a gene from an eel-like fish called ocean pout, which acts like an “on switch” for the growth hormone.

So how are they eco-friendly? According to John Buchanan, research director at AquaBounty, which produces the Canadian-designed fish (they were born at Memorial University in St. John’s, Nfld., in 1989), they cause “less degradation of the environment, less disease spread,” and require less feed. They can also be harvested in onshore containment facilities, he says, close to customers, which means less shipping. “The world population is growing,” he adds, “and the ability to produce twice the amount of fish for the same cost and time will be beneficial.”

It sounds like a sales pitch, but that argument is reiterated by Mart Gross, a professor in ecology at the University of Toronto and a former critic of genetically modifying animals. “Our population today is over six billion people, and is going to increase by 50 per cent. Where is the food going to come from? It’s not going to come from our old ways of farming.”

Experts say other fish, such as tilapia and cod, are next in line for genetic modification.

Meanwhile, genetic modification has been used by Scottish scientists to create chickens that lay eggs that contain proteins for cancer-fighting drugs. Russian researchers have created goats that produce human breast milk. A Canadian company owns the intellectual property for another transgenic goat. Its milk contains a protein that can be spun to produce high-strength materials (more eco-friendly than petroleum-based ones) for things like biomedical devices, or for use in the aeronautics industry.

Still, some researchers claim that instead of helping the environment, these novel animals could destroy it. The AquAdvantage salmon, while about 98 per cent sterile, could threaten natural populations if they interbreed. Mark Abrahams, professor at Memorial University, has conducted behavioural experiments and concludes that if the GM salmon enter environments where their natural predators have been depleted, they’d outperform wild salmon, putting those fish at risk.

“Most animals, when they are making a decision about where to go to feed, weigh the costs and benefits,” says Abrahams. “Transgenic salmon don’t. They are growing all the time, they need food, they go for it.”

Moccia says not to worry: “Society will make the ultimate call.” But will it? According to Grace Skogstad, a University of Toronto professor who researches the politics of genetically modified foods, the consumer has been the last to make decisions about what she eats in the U.S. and Canada. “In Europe,” Skogstad says, “there is this notion that there isn’t anything in genetic modification that benefits the consumer—it just benefits the producer—so governments have encouraged organic farming instead of modern farming methods.”

Nevertheless, if society can’t swallow the GM salmon option, another eco-friendly method of fish farming is being piloted on Canada’s East Coast. Instead of using cutting-edge technology, Thierry Chopin at the University of New Brunswick has been looking back to complex polyculture, an approach used centuries ago in Asia. With integrated multi-trophic aquaculture, salmon are grown in conjunction with mussels and seaweed. Different species have complementary functions in the ecosystem, so they balance each other out. “What we’re doing is like crop diversification in agriculture,” says Chopin, “which brings economic stability and reduces risks.” Water quality is improved, and mussels appear to reduce the virulence of infectious salmon anemia virus. Recently, Chopin’s team has also been exploring the possibility that mussels may filter and consume sea lice. If Chopin is successful, Canada may once again present a viable alternative to today’s fish farming.


 

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