Are we dealing with bad bacteria?
According to a survey at the Kansas State Veterinary Diagnostic Lab, the pathogen Mannheimia haemolytica was more resistant to antibiotics from 2009 to 2011.
Brian Lubbers, assistant professor at the lab, said a survey or records of BRD cases shows drug resistance has increased. “We have been seeing an increase in the number of antibiotic resistant bacteria that cause pneumonia (BRD) in cattle. Many of these bacteria are resistant to not one, but almost all of the antibiotics that we use to treat pneumonia in cattle.”
Initially, that news could give cattle producers grief, and most veterinarians admit it’s worth noting. However, it does not mean that suddenly, all antibiotics are not “working,” they say.
Dr. David Bechtol of Palo Duro Consulting says antibiotic resistance has always been a concern. It’s not new.
The problem, he contends, is two fold: 1) we’re finding the majority of resistant bacteria in dead animals; and 2) because of how animals are purchased, transported and handled, it will continue to be an issue, he says.
“Drug resistance is not a new problem. But the samples are all from dead animals, where yes, the bacteria can be resistant,” he says. “Your looking at an animal that’s had two or three doses of treatment and died.”
However, if all cattle carrying the bacteria were sampled — before they died — Bechtol has seen a large majority of the samples would be suceptible to today’s antibiotics.
“Swab the nasal passages of live animals and test that bacteria,” he suggests. “Know what you’re dealing with then.”
Bechtol admits there are some strains that don’t respond to today’s therapies, but a large majority of the bacteria found today do respond to treatment.
He contends if we did a better job as an industry vaccinating and handling high risk cattle, we would not struggle with as many drug resistant pathogens.
“We’ve got to change the way we handle cattle,” he says. “As long as we keep getting cattle through the salebarn, where they are exposed to many different bacteria, and these cattle haven’t been vaccinated properly at point of origin, there’s going to be a problem.
“Just because there are some resistant bacteria out there, it doesn’t mean our antimicrobials aren’t effective.” The stresses on that animal are multiplied because of our handling practices. That makes it much harder for a calf to fight an infection, he says.