Using DNA in human medicine is common, and now a Canadian packer, Maple Leaf Foods, is using the technology to trace its pork products back to the maternal sow.
In layman's terms, DNA is defined as the molecules inside cells that carry genetic information and pass it from one generation to the next.
"Ideally, we'd like to trace through all steps in the pork-value chain, from consumer to the farm," says John Webb, director of genetics and science, Maple Leaf Foods. "It's difficult to trace through the modern plant with different cutting lines and processes, but DNA allows us to trace back to the farm and bypass the plant."
Maple Leaf implemented the system in Alberta earlier this spring, with the goal of providing fully traceable pork products to the Japanese market by the fourth quarter of this year. The company plans to make the traceability system available to the Canadian pork industry sometime next year.
Chicago-based Pyxis Genomics worked with Maple Leaf to develop a panel of genetic markers. "Their job was to find the right genes that would identify the mother of a slaughter hog with very high probability," notes Webb. "They were looking for pieces of DNA that show variation across many different pigs. They came up with about 80 SNP's (single nucleotide polymorphisms, referred to as 'snips'), that are single-base-pair differences in the genetic sequence."
This traceability system works with all types of pork operations. The process is fairly simple. Maple Leaf sends a supply of blood tubes to each farm. The producer or veterinarian takes a blood sample, records the ear tag number and applies a bar code on the corresponding tube. It's then sent to the DNA lab for genotyping. At the lab, the DNA genotype is entered into a database linked to the farm-of-origin information. Producers can update the database directly with each litter's birth dates.
With this information, Maple Leaf can trace pork products from the farm to the actual packaged product by using only a tiny piece of its tissue. And, it doesn't matter if it's ham, bacon or a pre-cooked product, like a pork chop.
"DNA traceability is an effective tool for tracing a product from the retail market back to an animal or a farm," says Mark Engle, director of swine health programs, National Pork Board.
He notes that as DNA traceability becomes more common; and applications and added-value opportunities are identified, that it also will become more feasible and cost-effective.
The entire process costs approximately $50 to $55 (U.S.) per sow. Maple Leaf's philosophy, Webb says, "is that traceability is only worth doing if it adds value in terms of price or greater market share. The system will have to earn the money; the producer won't have to pay for this up front."
The program's initial phase will involve 20,000 to 30,000 sows, from about 40 pork operations, according to Webb. "Later we will probably use the traceability system on high-value products going to Japan. We are planning to make the system available to the entire Canadian pork industry by the end of the year."
Canadian pork producers consider the program welcome news. "Last year was not a good one, and they didn't want to be in a position to pay for this program up front," says Webb.
Once the program reaches its second year, only a producer's replacement sows will need DNA typing, so costs will be a lot lower. "We (Maple Leaf) haven't addressed the question of the program's cost/benefit structure," he notes. "However, the benefits would need to be at least $1.37 (U.S.) per carcass to cover the costs. For example, if Maple Leaf receives all of the benefit, producers won't have to contribute to the costs."
"The beauty of DNA traceability programs like Maple Leaf's is that it really doesn't affect anything in the plant," says Engle. "It doesn't have to track meat when the carcass is broken down as long as they have the up-front DNA obtained from the sow farm."
There are many benefits to having a traceable pork chain. Webb outlines these advantages:
Increasing concern about food safety. Webb notes that one of the large European retail food chains took out full-page ads that read: "We can trace it, so you can trust it."
Help in containing a serious animal disease, such as the foot-and-mouth virus. The advantage, explains Webb, is that it wouldn't be necessary to close down all of North America because the meat could be traced to a specific area. The hope is that export markets would accept meat from unaffected regions.
Ability to trace potential drug or pesticide residues. Also, if a hypodermic needle is found in a piece of meat, you can recall the specific lot much more easily, greatly reducing losses.
Proof of product origin. Not only can Maple Leaf prove that the meat came from Canada, but also that a certain group of hogs was fed or raised s certain way. That's especially important to the Japanese market, notes Webb.
The system is cost-effective. It's also difficult to cheat because every piece of meat has its own natural barcode, and an independent lab does the typing.
"Certain markets are willing to pay for added-value through production traits, and this can help you verify your production process," adds Engle.
In terms of cost, Webb predicts costs will drop in half within the next three to five years, and eventually be pennies per carcass. "This idea was a dream a few years ago. But it will get cheaper just like computers and other technology," he says.
The next step for Maple Leaf officials will be to try and find cost-effective ways to trace meat through the packing plant. Right now, Webb estimates it would cost $50 million and add $4 to $5 (U.S.) to each carcass to implement a traceable system in a large packing plant like the one in Brandon, Manitoba.
"We do have the technology, but being able to read DNA in real time is a long way off," says Webb.
One drawback from a U.S. standpoint is that Maple Leaf's system doesn't accomplish what the U.S. livestock industry needs for live-animal traceability.
"Their system can tell you when an animal was born on a farm, but it doesn't tell you what happened to the animal before it went to market," explains Engle. "However, as the technology becomes more cost-effective, I believe more niche markets will utilize it."
"We're trying to safeguard the future of meat in market terms and raise the confidence of meat buying around the world," says Webb. "We're all working together to try to preserve meat's position and recognize the damage that one or two cases of BSE can do."
The bottom line is that Maple Leaf officials see this program as an opportunity to strengthen Canada's position as a major global pork exporter. It may not cover all of the bases just yet, but it's certainly a big step in a new direction.