Dr. Bo Norby, associate professor for the Department of Large Animal Clinical Sciences, also studies bacteria, though his focus is antimicrobial-resistant bacteria in dairy cattle and how farmers can reduce transmission of the pathogens as well as reducing the resistance to antibiotics.
In the past, many farmers that produced food animals mixed antibiotics in the animals’ feed to promote growth and for feed efficiency. While this practice has stopped, farms that did use antibiotics in feed are slow to recover from antibiotic-resistant bacteria in herds. The more time it takes for antibiotic resistance to diminish, the higher the risk of resistant bacteria transmission among animals and between animals and people. Ultimately, the resistant bacteria make treatment of bacterial disease in all species more difficult.
“Unfortunately, the prevalence of drug-resistant bugs isn’t going to just drop off right away in most instances, but I want to find out if there’s a way to speed up the decrease in prevalence of resistant bacteria, instead of potentially waiting for many years or decades to pass,” Norby says. “The question is, can we speed up the process, and if we can, which new protocols can we implement to aid in that pursuit?”
“. . . As we learn more about antibiotic resistance and how to prevent and reduce it, we can create novel therapies, develop farm management practices, and
implement reductions in antibiotic use that will make the world a healthier place for everyone.”
To speed calf recovery from resistant E. coli bacteria, Norby developed a probiotic therapy that decreased bacteria numbers by 90 percent. He’s also working with dairy producers to identify how they can reduce antibiotic use with the goal of easing build-up of antibiotic resistance in the first place.
“Investigating new therapies like this probiotic can accelerate the reduction of antibiotic-resistant bacteria in herds and could lead to improved health for animals and food safety for humans,” Norby says. “It can be hard to change behaviors, even when there is economic incentive to do so—at MSU, I’m working with my fellow faculty and members of other colleges and MSU Extension, as well as primary care practitioners and producers, to navigate the human and social dimension of this problem. As we learn more about antibiotic resistance and how to prevent and reduce it, we can create novel therapies, develop farm management practices, and implement reductions in antibiotic use that will make the world a healthier place for everyone.”