Air Date: Week of July 2, 1999
In an attempt to deal with excess phosphorus in pig manure, scientists at the University of Guelph , Ontario, have invented an "Enviropig." Some high-tech gene splicing has produced a pig which does a better job of processing phosphorus in its feed. Cecil Forsberg spoke with host Steve Curwood about the development.
CURWOOD: Pig farms stink, and when all the pig manure they generate isn't contained, it can get into surface water and cause health and ecological problems. In particular, high amounts of phosphorus found in pig manure contribute to algal blooms in water bodies that kill other life forms. But 3 scientists at the University of Guelph, Ontario, say they have a partial solution. They've created a pig -- well, 3 pigs in fact -- who were injected with a spliced bacterium and mouse gene while they were embryos. The gene allows the pigs to better digest phosphorus in their feed, in effect creating environmentally friendly…poop. Dr. Cecil Forsberg, one of the lead scientists and inventors of the “enviropig,” explains why the usual menu of pig feed causes problems.
FORSBERG: The cereal grains, for example, the barley, the oats, the corn that the pig eats, contains this indigestible material called phytate. And the pig is unable to digest it normally, so that they, the farmer will add in a mineral phosphorus material to get the right proportions of nutrients in the ration. Now, our invention is to modify the pigs who can actually utilize this indigestible plant phosphorus, and as a consequence the farmer won't have to add in that additional mineral phosphorus. And also, when it can utilize this indigestible plant phosphorus better, what it means is that there's less excreted in the manure.
CURWOOD: So, your invention, the “enviropig,” cuts the amount of phosphorus that comes out of the back end of the pig and thereby helps the environment.
FORSBERG: That's what we hope we will achieve.
CURWOOD: Well, how do pig farmers handle the problem of phosphorus today? I mean, if they have runoff and it causes pollution, they must, you know, get into a fair amount of trouble. We've covered stories about this, in fact. So how are they handling the phosphorus right now?
FORSBERG: Currently, farmers feed the enzyme phytase to reduce the level of phosphorus pollution in the manure, so that's a current solution. And our innovation is actually to have the animal synthesize this phytase enzyme themselves.
CURWOOD: Why not just feed them the phytase?
FORSBERG: Well, that's a very good option. The one aspect is that it's more expensive to feed phytase to pigs than to have them use that small amount of incremental energy and nutrients required to synthesize their own. The other aspect is that this way, all of the pigs will have it all the time, and the farmer can simply forget about the feeding of this additional component in the ration.
CURWOOD: So, you took some bacterium, you took a salivary gland gene out of a mouse, you put this into the genetic structure of a pig. Now, if this genetic modification interferes with the ordinary metabolism of the pig, might it otherwise cause metabolic problems?
FORSBERG: That is always a potential and an aspect that we are, as everyone else, very concerned about. And that will also be part of the research to check to see if it has any influence on the behavior or the metabolic characteristics of the pig. And obviously, if it does have any deleterious effects on the pig, the research won't, or this aspect of the research won't go any further. However, in defense of that, I can say that we have 3 piglets born so far. The oldest one is almost 3 months old now. And all 3 piglets look extremely healthy, and they're growing at normal rates.
CURWOOD: Have you drawn any protests or concerns from people who worry about the consequences of genetic engineering?
FORSBERG: So far, I have heard no criticism of our research or the ethical aspects related to it, although I am very well aware of a lot of criticism of genetically modified crops, and I expect there will be dissenters.
CURWOOD: How easy will it be for you to get approval from the Canadian government to market these pigs?
FORSBERG: That's something we don't know at the present time. And I can't speak to it in any great depth, because the actual regulations on transgenic animals here in Canada, they are in fact in the formative stages.
CURWOOD: Well, I wanted to ask you, how soon do you think that these pigs will be ready for market and will get through government approval?
FORSBERG: We are currently saying some 5 to 6 years if the pigs do in fact have the capacity to decrease the phosphorus in the fecal material and yet maintain their productivity in terms of growth rate and meat quality. Although it may be premature to reach these conclusions, since we are not certain yet all of the government hoops that we will have to jump through before we get to the point that they can be released.
CURWOOD: All right. Well, I want to thank you very much for taking this time with us today.
FORSBERG: You're very welcome. It's most enjoyable to chat about the Enviropig.
CURWOOD: Cecil Forsberg is a microbiologist at the University of Guelph in Ontario and one of the inventors of the Enviropig. Thank you, sir.
FORSBERG: You're welcome.
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