Iowa State University (ISU) researchers have found that certain antibiotics encounter more resistance from Campylobacter coli than other antibiotics, with some variation of resistance levels between farms, according to the Food Safety Consortium.

"If we can eventually figure out what the actual risk factors are associated with resistance we'll be able to manage that and reduce the risk," said Qijing Zhang, an ISU professor of veterinary microbiology who managed the project for the Food Safety Consortium.

Zhang's team, in collaboration with Irene Wesley at the U.S. Department of Agriculture National Animal Disease Center, reportedly gathered C. coli isolates from different production stages at two Iowa swine farms and tested their ability to resist five different antibiotics. The pathogens were unable to resist two antibiotics -- gentamicin and meropenem -- but there were varying levels of resistance to three other antibiotics.


Those three antibiotics' abilities to stave off C. coli varied among each other and between the farms. The levels ranged from 65% of C. coli isolates on one farm resisting one antibiotic to 7.3% on the other farm. The antibiotic doxycycline reportedly encountered the most resistance, with the antibiotics erythromcin and ciprofloxacin encountering lower resistance rates.

The ISU researchers are considering following with another phase of research into the subject. "We're not going to abandon this project," Zhang said. "This is a long-term interest for our research."

              Qijing Zhang