Canada's largest packer unveils a DNA-based tracking system to identify pork back to the farm of origin.

Maple Leaf Foods has successfully completed testing of their new DNA-based pork tracking system, making it possible to trace the meat from any Canadian-born hog, marketed anywhere in the world, right back to the farm of its birth.

The system, expected to be operational early in 2004, can quickly, accurately and cheaply trace any slice of bacon back to its farm of origin. The company plans to make their technology available to the Canadian pork industry next year.

How It Works

Live animal tracking can be done fairly easily with a tagging system. Retail tracking is simple with computerized bar codes. The problem to date has always been tracking animals through the processing plants. The Maple Leaf system avoids this headache by tracking animals by their DNA.

“DNA has the advantage that you won't have to trace it through every step through the plant,” says John Webb, director of genetics and science with Maple Leaf Foods in Toronto, Ontario. “We can start with a piece of fresh pork, ham, sausage or even partially digested product and you can get back to the farm of origin using the DNA code, the animals own innate bar code.”

The Maple Leaf system tracks a piece of meat back to the mother of the slaughtered pig. From there, the live animal tracking system follows it from the mother at the breeding farm, through the nursery, the grower, the finisher, the transport, all the way to the plant.

“It is a very, very easy system for the producer to use in practice,” Webb says. Whenever a replacement gilt is brought into the herd, they simply take a blood or hair sample and place it in a tube with the identification number. The sample is sent to a lab where it is DNA typed and entered into a database along with the farm of origin information. From then on, the producer need only submit the date of birth of each litter that sow has.

“Later, if someone finds a piece of meat that they either like very much, or don't like, and want to know where it came from, all they need to do is (DNA) type it and enter the DNA type into the database,” he continues. The database will then automatically match that DNA type with the farm where the slaughtered pig's mother originated, and the live animal trail can trace back to the plant.

How They Did It

Last December, Maple Leaf contracted Pyxis Genomics, in Saskatoon, Saskatchewan to find and develop a DNA panel — a collection of DNA sites — that had enough naturally occurring DNA variations to discriminate be-tween individual mothers.

The job was a lot like searching for the proverbial needle-in-the haystack. A single gene contains approximately 20,000 bits of DNA bases or nucleotides that, in combination, make up an animal's genetic code. They used techniques developed by forensic science to sift through these thousands of bits of code to find those with enough natural variation to identify an individual animal.

The search started by identifying sites that showed natural variation in individual animals, Webb explains. “Sites that are single-unit changes in the code are known as single nucleotide polymorphisms or SNPs (pronounced snips for short). Using these sites gives you a digital yes/no situation, providing there is no human error. Typing is 100% accurate.”

Unlike police forensic labs, which often have to meet tight deadlines, typing replacement gilt DNA can be done at a more leisurely pace.

“If we type a replacement gilt when she comes into the herd, then it is going to be four months until she farrows and a further five or six months until her progeny appear in the slaughterhouse,” Webb says. “We have a good three or four months to do the DNA typing. This means we can put together very large batches and use very high throughput, low cost, DNA typing.”

Webb estimates that DNA typing currently costs $35/gilt. If a sow has 70 piglets in her lifetime, then the DNA typing cost amounts to about 50¢/carcass. DNA testing is getting cheaper all the time and within three years costs are expected to come down to about $10/sow — just pennies per carcass. Meat typin costs will remain the same.

“While the traceability system requires every sow to be DNA typed, it won't be necessary to routinely type every piece of meat,” Webb says. “We are only going to type a small sample of meat, either when there is a problem, or when the customer wants to satisfy themselves that we are, in fact, right and the meat did come from the right farm. We will type any meat of exceptionally good or bad quality for our own breeding program as a means of learning more about how to improve quality,” he adds.

The ‘Holy Grail’ of Traceback

“There are a number of biotech companies that are offering DNA typing,” explains Webb. “But this is the first tracing system that is ready to go. It will be quite a coup for the Canadian industry.”

In an era when consumers are demanding to know where their food comes from, the search for a fast, accurate and inexpensive tracing system has become a modern day Holy Grail for food processing companies. Webb says the system gives the Canadian industry three main advantages:

  1. “Traceability creates a point of difference for Canada, and for Maple Leaf Foods, in particular. It gives us a competitive advantage when marketing the Made-in-Canada brand. With this system, the customer can verify what we say when we promise things like grain-fed, antibiotic-free and so on.

    “It's the small size, good communications and cooperation in the Canadian industry that makes establishing a national traceability system a real possibility,” he says. “The nice thing for Canada is that while some of the large American integrators might be able to physically do the same thing, it is going to be very difficult for the U. S. to do something similar on a national level. I think the Canadian industry could have a real advantage here.

  2. “It permits zoning for animal disease if we are unfortunate enough to get something like foot-and-mouth disease in Canada. We may be able to say that certain geographical areas can be guaranteed free of disease and go on exporting. Knowing that we have this capability increases our credibility in overseas markets.

  3. “A lot of traceability is about image, but there also is a very real threat all the time from disease, bio-terrorism or contamination. This system will let us trace any kind of contamination that may happen and lets us recall any product that may be contaminated. In an emergency, say a bio-terrorism attack or an outbreak of salmonella, you can type the DNA of the meat very quickly and find out where it came from. It doesn't matter where in the world this emergency occurs since it can be (DNA) typed by any lab. We just email them the code and they can type the meat right there and then.”



Webb adds that the Maple Leaf tracing system will also offer a simple way to verify a Canadian pig's point of origin if country-of-origin regulations become mandatory in the U.S.