Sign up now!
Don't show this again
Download the report!Continue to Site >
or wait 7 secs

Thank you for confirming your subscription!

(And remember, if ever you want to change your email preferences or unsubscribe, just click on the links at the bottom of any email.)

We’re glad you’re enjoying Pig Health Today.
Access is free but you’ll need to register to view more content.
Already registered? Sign In
Tap to download the app


Collect articles and features into your own report to read later, print or share with others

Create a New Report


Read Later

Create a new report

Report title (required) Brief description (optional)
follow us

You must be logged in to edit your profile.

Favorites Read Later My Reports PHT Special Reports
Pig Health Today is equipped with some amazing (and free) tools for organizing and sharing content, as well as creating your own magazines and special reports. To access them, please register today.
Sponsored by Zoetis

Pig Health Today | Sponsored by Zoetis

Featured Video Play Icon

Antimicrobial resistance causing few clinical problems in swine

Watch the full interview or each part separately

Antimicrobial resistance causing few clinical problems in swine

Part 1: Good news for the industry

Part 2: Better information equals better decisions

Part 3: Challenges of producing without antibiotics


Clinical problems in swine due to antimicrobial-resistant infections are rare, Peter Davies, BVSc, PhD, professor, University of Minnesota, told Pig Health Today.

Patterns of resistance in swine have been stable for a long time. The only two pathogens in swine that may result in clinical management challenges due to antimicrobial resistance (AMR) are Escherichia coli and Streptococcus suis. Although there are certain multi-drug-resistant serotypes of Salmonella that could be a concern because they are foodborne pathogens, Salmonella infections in swine are uncommon, and they are “a relatively unimportant problem except in individual herds rather than across the industry,” Davies said.

VFD impact uncertain

It’s too soon to tell if the decreased use of in-feed antibiotics initiated by the updated veterinary feed directive that took effect in January 2017 has had an impact on AMR. “We may never directly answer that question,” and there would have to be a very large impact on resistance to be able to measure it with existing systems, he said.

The professor cited the experience in Holland, where there’s been a 50% to 60% reduction in the total use of antibiotics in farm animals and a 20% reduction in E. coli resistance. That’s based on measuring the percentage of E. coli susceptible to all the antibiotics tested. Testing for resistance of just one organism, however, is “sort of looking at a very small slice of the pie,” and more meaningful surveillance of resistance in the animal population is needed, Davies advised.

Learning curve

He questioned the value of linking AMR to the amount of antibiotics used. There’s a lack of understanding about the relationship between patterns of antibiotic use and how that translates into changes in patterns of resistance at an ecological level. “…with certain drugs, particular drugs, we can see that there have been changes in resistance patterns, but what that actually means in terms of public health risks or potential environmental implications — we’re still very early in the learning curve, I think.”

Davies likewise discouraged comparisons of antimicrobial use among different food-animal species because they have such different biology and management. The problems for each species should be defined and addressed within their own systems, “and I like to extend that to antibiotic use as well.”

What is essential, Davies said, is the clinical application of results from AMR surveillance because having better information always leads to more-informed practitioner decisions. That’s one reason why susceptibility testing is often obtained in the swine industry. It’s still the best information practitioners can get. Similarly, AMR surveillance is good for the industry.

Susceptibility testing in the swine industry is also common because herds have gotten bigger and so have the implications of treatment decisions, Davies said. However, he thinks the main value of getting better information on antibiotic use is really to promote education, to promote stewardship “and again advance the discussion with some quantitative data on what’s actually going on. I think that will help move the veterinary profession and the industry forward…”

He expects most susceptibility testing will continue to be based on phenotypic testing of cultures from diseased animals. Molecular methods — particularly next-generation sequencing — currently are used primarily in the research arena, but eventually, it will lead to a better understanding of the ecology of AMR in animal populations. “New technology is going to take us a long way in the next 5 to 10 years,” he predicted.

Share It
Patterns of antimicrobial-resistant infections in swine have been stable for a long time. So why continue to do AMR surveillance?

Click an icon to share this information with your industry contacts.

Posted on June 18, 2020

tags: ,

You must be logged in to edit your profile.

Share It
It’s not unrealistic to say that if you checked the nasal cavities or tonsils of any group of pigs, you would find Strep suis. While the strain and impact can vary widely, this commensal bacterium is on virtually every hog farm.

Click an icon to share this information with your industry contacts.
Google Translate is provided on this website as a reference tool. However, Poultry Health Today and its sponsor and affiliates do not guarantee in any way the accuracy of the translated content and are not responsible for any event resulting from the use of the translation provided by Google. By choosing a language other than English from the Google Translate menu, the user agrees to withhold all liability and/or damage that may occur to the user by depending on or using the translation by Google.