Posted on February 18, 2011 - by

Enviropigs, Coming to a Plate Near You?

Photo: National Geographic

Deep in a lab in Ontario, Canada, scientists are hard at work finding greener solutions for the waste streams generated by large-scale factory farms. No, we’re not talking about toilet-trained pigs. These Enviropigs have been engineered from conception to be less polluting.

The Enviropig is a project from the University of Guelph, and is line of genetically-modified pigs designed to produce manure that contains less phosphorus. Phosphorus is a nutrient necessary for plant growth, but if it is spread too intensively on fields and not absorbed, the phosphorus becomes a pollutant. When there is a deluge of phosphorus runoff, the resultant algae blooms can deplete the water of oxygen, resulting in dead zones and fish kills in local rivers and streams.

In the US and Canada, pigs are mostly fed corn and grains, which contain a form of phosphorus that is indigestible by pigs. To combat this, pigs are usually given a phytase supplement, an enzyme that helps pigs break down this type of phosphorus. However, the phytase does not break down everything, and a significant amount of phosphorus is still excreted by the pig.

The Enviropig has been modified to secrete its own phytase, which works more efficiently than a dietary supplement. Thus, 30 to 70.7% less phosphorus is excreted, reducing phosphorus pollution and manure treatment costs, and decreasing the amount of phytase supplement that is needed (Univ. of Guelph). To accomplish this, researchers isolated a gene in e. coli bacteria that breaks down phosphorus and incorporated it into the pig genome. Not only was the implantation successful, but the offspring of the pigs also inherited the modification (National Geographic).

So, the phytase supplement has been used in large hog operations for over a decade, and now we can have pigs that produce it naturally in their salivary glands. Woohoo, this is an innovative milestone in greener farming, right?

Not so fast. While the Enviropig may reduce phosphorus emissions, it does nothing to address the destructive issues underlying factory farming. Manure and phosphorus are assets in agriculture, and only become liabilities when animals are intensively farmed in a single location. Reducing the amount of phosphorus excreted does not resolve the myriad other issues that factory farming raises, like the spread of disease, animal welfare, nitrogen pollution, the loss of biodiversity, etc. Worse, the availability of the Enviropig may lead farmers, policy makers and consumers to believe that this is a panacea for factory farming, and that the practice is environmentally sound.

Besides, there are alternative ways to reduce phosphorus without resorting to genetic modification. By including fewer grains in the pigs’ diets and using phytase supplements, phosphorus excretions can be reduced up to 50% (CBAN). In addition, the cost of phytase supplements has dropped dramatically in recent years, to less than $5 per kilo, and one metric ton of feed only requires 250 g of phytase supplement, which works out to a cost of less than 25 cents per pig (Sean McGivern).

Commercializing the Enviropig will make it nearly impossible to control the spread and proliferation of this gene, as the pigs intermingle with conventional pigs. Farmers who may not want to raise genetically-modified pigs will be hard-pressed to avoid genetic contamination of their livestock. Finally, consumers are wary of genetically-modified meat, and may not even accept or purchase the product. So why bother genetically modifying animals when there are other solutions at hand?

The answer, as is often the case, is money. The University of Guelph holds patents and is looking to license the Enviropig for use, charging royalties on a product for which there are currently none. This will be an added cost to hog farmers, and require some kind of enforcement mechanism, much like genetically-modified seeds which are sterile. At any rate, in some way or form, someone will have to pay.

By the way, the Enviropig has been submitted for review by the FDA and Canadian regulators, so expect to hear about the Enviropig’s potential commercialization in the near future.

In a debate with the lead researchers from the Univ. of Guelph, Sean McGivern, hog farmer and regional coordinator of the National Farmers Union Ontario, concluded with the following declaration: “We need our universities to work on issues that empower farmers, and not depower farmers, such as the Environpig. The reason universities do not spend their time researching things that empower farmers is simple—most of those things do not return profits to multinational corporations and family farms simply do not have the money to pay for research to help keep the doors open at universities like Guelph. The university researchers are bought and sold, like the Environpig they were hired to create.”

Do the benefits of the Enviropig outweigh the costs? Give that Americans already eat many products with genetically-modified corn and other plants, would you eat genetically-modified meat? What can we do to better align the interests of researchers and scientists with small-scale farmers?

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    February 20, 2011


    Millie said:

    Have tested to see if the reduced phytase would reduce the phytase in humans?

    Unintended consequences!!!