Genetically Engineered Pigs More Environmentally Friendly

Recently approved for limited production in Canada, the “Enviropig” could be good news for rivers, lakes and ocean deltas where phosphorous in animal waste can lead to algal blooms. “These outbursts of algae rapidly deplete the water’s oxygen, creating vast dead zones for fish and other aquatic life,” Anne Minard explains for National Geographic News.

Enviropig has been engineered to make its own phytase, an enzyme that helps the pig digest the phosphorous that naturally occurs in the plants it eats. As a result, the pig absorbs more of the phosphorous in its feed, so less of it passes through the pig and is excreted in waste.

It could take years before the new pig passes tests in the United States and Canada for human consumption or commercial use, but the pig’s creators are hopeful.

“This will be probably the most significant transgenic food to be approved,” Steven Liss, an environmental scientist at the University of Guelph in Ontario, Canada, and a spokesperson for the project, told Minard. “We’re in new territory.”

Even though the Enviropig was engineered to address a major environmental hazard—water pollution—many environmentalists argue that all genetically modified products should be banned. As Leora Broydo Vesel wrote for Mother Jones magazine in 2001, “While the hogs’ virtues may be attractive to the green groups, their modified genes represent a vice too significant to overlook.”

The Sierra Club, which was lobbying for controls on pig farming as part of its clean water campaign, was particularly vocal. “This is just another quick fix,” Laurel Hopwood, chair of Sierra Club’s genetic engineering committee, told Mother Jones. “The way to reconcile [the problem] is to stop factory farming.”

Others point out that there are less costly solutions for the problem of reducing phosphorus output in pig manure: A new breed of corn, for example, reduces phosphorus by up to 50 percent, and the common practice of adding the enzyme phytase to pig feed reduces phosphorus by 56 percent.

“There are a lot of sustainable agriculture programs that offer real benefits to food security and to the environment that take far less resources than the biotech solutions being proposed,” Michael Khoo of the Union of Concerned Scientists told Mother Jones.

To date, no genetically engineered animal has been approved for consumption in the United States. In 2008, however, the FDA approved a drug manufactured using milk from altered goats. The drug, a blood thinner called ATryn, was created by injecting DNA from human antithrombin protein—a protein that acts as a natural blood thinner—into single cell goat embryos. These embryos were then implanted into the wombs of surrogate goats that gave birth to baby goats that produce extra antithrombin in their milk.

The Asian Citrix Psyllid has spread the devastating “greening disease” across Florida citrus groves since its accidental introduction to the United States less than a decade ago. To control the Asian Citrix Psyllid and other invasive species, the U.S. Department of Agriculture’s Animal and Plant Health Inspection Service has said it would allow the introduction of genetically engineered predators, or transgenic insects, which would feed on pests without disrupting other species.

The University of Guelph explains that the “Enviropig is a genetically enhanced line of Yorkshire pigs with the capability of digesting plant phosphorus more efficiently than conventional Yorkshire pigs.” Visit the site to view a diagram of the pig and read more information on societal issues and environmental benefits.