A new pilot project will give Canada’s cattle industry some long-overdue and much-needed data about antimicrobial use and resistance on Canadian beef farms.
“Antibiotic resistance is a really, really big deal, both for human and animal health,” said Reynold Bergen, science director for the Beef Cattle Research Council.
“If bugs get resistant to antibiotics, the antibiotics won’t work anymore, and then we’ve got big problems.
“Ultimately, for producers, we need these tools to continue to be effective so that we can maintain animal health and welfare.”
But it’s not just farmers who are worried about antibiotic resistance in their animals, said Bergen. Increasingly, retailers are setting targets for antibiotic use in the meat they sell or shifting to antibiotic-free meat altogether.
This trend, driven largely by consumer demand, has already influenced government policies around antibiotic use in livestock. Last December, the federal government increased veterinary oversight on on-farm antibiotic use, requiring a prescription for around 340 antimicrobials that had been previously available over the counter.
The problem with these types of regulatory changes, said Bergen, is that there isn’t much science around the actual rates of on-farm antibiotic use and resistance in beef cattle.
That data exists in other livestock sectors, though.
Since the early 2000s, the Canadian Integrated Program for Antimicrobial Resistance Surveillance (CIPARS) has been monitoring antibiotic use and resistance in all livestock. But its on-farm component has largely been limited to pigs and broiler chickens, as those were the animals considered at highest risk for antibiotic resistance.
In the last year, its on-farm services have expanded to dairy cattle and turkeys, but because of budget constraints, beef cattle had been put on the back burner, said Bergen.
“But what that means is that, as an industry, we’ve got no data to back up that we’re using antibiotics responsibly on farm,” said Bergen.
“So we need facts — partly to defend our production practices and to reassure consumers we’re doing things right, but also to identify where we can do better.”
And those facts are coming, thanks to additional government, beef industry, and pharmaceutical sector funding. Over the next three years, CIPARS will be partnering with feedlots and feedlot-focused veterinary practices in Alberta, Saskatchewan, and Ontario on a three-year pilot project looking at antibiotic use and resistance in these three major cattle-feeding provinces.
“This is not the first project of this type, but it’s one of the most comprehensive because it ties use in with resistance,” said Dr. Craig Dorin of Veterinary Agri-Health Services in Airdrie, one of the practices involved in the project.
The first piece of the project will focus on determining which pathogens exist in the feedlot, said Dorin.
“I think we already have a good handle on that, but part of surveillance is looking at the same thing over and over again to see if there have been changes over time.”
That ongoing surveillance will also compare resistance in geographic areas relative to how antimicrobials are used in those areas, he added. This will allow the beef industry to monitor trends around antimicrobial use and resistance — particularly for antibiotics that might also have an impact on human health.
“What this will help us do is identify trends over time — are we seeing an increase in use or an increase in resistance?” said Bergen.
“Either way, knowing helps us see whether we’re on the right track or if we need to make some adjustments.”
For Dorin, that’s the most important piece of this study.
“We are producing food, and the people who consume the beef that we produce need to have a high level of confidence that the products we use on these animals are used prudently and appropriately,” he said.
“Part of prudent use is selecting the right antimicrobial for the right situation — using not only an antimicrobial that will be effective against the disease you’re trying to prevent, but one that will also have minimal impact on the potential resistance that might be transferred into the human population.”
But this study will also give retailers a baseline to create science-based targets for antibiotic use in the meat they sell.
“Some retailers are going antibiotic free and others are wanting to set targets to reduce antibiotic use,” said Bergen. “And with data like this, they’ll have a sense of where they can make a meaningful difference.”
That will be particularly important for respiratory pathogens such as bovine respiratory disease, Bergen added.
“That’s why a lot of these antibiotics are being used — to manage respiratory disease,” he said. “So if you can get a sense of why they’re being used for respiratory disease and what degree of resistance is there, you’re tying it much more closely to management decisions than you would with any other retail meat.”
But it will be tricky for a study like this to actually drive on-farm management decisions in the short term, Dorin cautioned.
“That’s going to be a part of it — to make sure that the antibiotics that we’re using are still the correct choices — but it’s not going to drive day-to-day decisions,” he said.
“Day-to-day decisions happen very quickly, and this is a study where we’ll be looking at annual results. We’ll be able to look at year-to-year changes, but we won’t be able to get down to the level of week-to-week change at a particular farm.”
But that technology is coming. Another study, set to start in the next year, will explore rapid genetic testing for respiratory pathogens.
Right now, the turnaround time for samples sent to the lab can be anywhere from a few days to up to a week — and a lot can change in a week, said Bergen.
“Those results tell you what you should have done a week ago if you had known at the time,” he said. “But between a week ago and today, that animal could have got way sicker, and it could be way different bugs that are causing the problem now, and they could have a different antibiotic-resistance profile.”
But as genetic testing technologies improve, rapid diagnostics could change that, Dorin said.
“This new genetic testing would allow results to be back within hours instead of days,” he said.
“Our hope is, over time, those hours will turn into minutes, and then when a sick animal comes in, we can test it and know exactly what antibiotics should be used on that animal on that day.”
That will go a long way toward maintaining the antibiotics available to cattle producers.
“We have a limited number of products available for use in the beef industry,” said Dorin.
“It’s expensive to bring these products to market, and it gets more expensive as time goes on. We’re worried that resistance may be developing faster than our ability to produce new products, so reducing our antimicrobial use in favour of other management practices — like low-stress weaning — is important.”
“Antibiotics have been so effective for so long that they’ve become a valuable tool, but because they’ve been so effective, there’s been a little less need to find alternatives,” he said.
“There’s a chance — and not a remote chance — that 50 years from now, the antibiotics we’ll have available to treat animal diseases might be the same ones we have now.
“So we’d better use the ones we have now responsibly so that they keep working down the line.”