Hog producers who use antibiotics that are also used in human medicine should review use and prepare for changes.
Dr. Leigh Rosengren, a veterinary epidemiologist, said ceftiofur, which is marketed as Excenel and Excede, and enrofloxacin, which is marketed as Baytril, will come under more scrutiny in the future as the federal government seeks to address the problem of antibiotic resistant bacteria.
Ceftiofur and enrofloxacin are used to treat serious human infections, and few alternatives are available if bacteria develop resistance.
Rosengren said extra-label use of those products in hog production will likely not be allowed in the future.
“Be very, very acutely aware of why you’re using them, if there’s any other options that you could be using and to understand the consequences of using those products if resistance emerges,” Rosengren told an April 2 Alberta Pork teleconference.
“We need to think of the cost, both the actual tangible economic cost of the drug but also the larger societal cost of resistance relative to the immediate benefit in your herd of the use.”
Rosengren said antibiotic use for growth promotion and disease prevention have become consumer concerns. However, fewer producers are using the products only for growth promotion.
“This use has really tailed off in the last few years, both because we’ve become more acutely aware of some of the concerns of what this can bring as far as resistance but also because nutrition and management, husbandry, hygiene, those things have improved so much that we don’t have that same need for them for growth promotion.”
Hog veterinarian Dr. Egan Brockhoff agreed with that assessment.
“We don’t see a lot of quote unquote growth promotion use at all anymore on the farms that I work with.”
However, hog producers who use antibiotics are still contributing to the development of antibiotic resistant bacteria, said Rosengren.
Producers often ask her that question, she added.
Bacteria can contaminate an animal carcass, and those bacteria can be ingested if the meat is improperly handled or prepared. Ineffective treatment of the resulting illness can be a sign that the bacteria are resistant to common cures.
“That chain of events, in theory, can be related to the antimicrobials that were used on that farm or in that situation,” she said.
“Now, the chain is long. The chain is difficult to measure … but there is a chain there and for that reason there is very intense scrutiny on what we’re doing in agriculture for our antimicrobial use.”
Rosengren said some estimates indicate that up to 70 percent of E. coli bacteria commonly found in the hog industry are resistant to tetracycline. That drug is not commonly used in human medicine.
Less than five percent of common hog industry bacteria are resistant to the antibiotics of high importance for humans.
“We are using some of those products in certain circumstances on our farms so resistance could emerge, and once it’s emerged it’s incredibly hard to deal with,” she said.
Regulations will require greater veterinary involvement in drug choices and use. Drug label claims for growth promotion will be phased out by December 2016.
Rosengren encouraged producers to consider drug use carefully in their herds.
“Every producer should know what they’re using, where they’re using it — feed, water, injection — and why they’re using it and what they would expect health-wise were they not using it in that circumstance.”
Failure to do so could result in the loss of some products for hog production use.