Are There More Bacteria Involved in Spreading Bovine Respiratory Disease and Antimicrobial Resistance Than We Think?
Project Title
Phenotypic and Genotypic Characterization of Antimicrobial Resistance of Bovine Respiratory Disease Complex Neglected Bacteria
Researchers
Tim McAllister [email protected]
Athanasios Zovoilis, (University of Manitoba), Sheryl Gow (Public Health Agency of Canada)
| Status | Project Code |
|---|---|
| In progress. Results expected in May, 2027 | ANH.05.24 |
Background
Aside from antibiotic treatment, little progress has been made controlling bovine respiratory disease (BRD) in feedlot cattle. BRD research efforts usually focus on Mannheimia, Pasteurella, and Histophilus, butother bacteria may be involved (Trueperella, Bibersteinia, certainly Mycoplasma). If our vaccines and antibiotics only suppress the pathogens we know about, current prevention and treatment strategies may leave the field open to some of these less well-known bacteria to cause problems. On top of that, antibiotic resistance genes are often found on Integrative Conjugative Elements or ICE. Bacteria can trade these like baseball cards. This team has found ICE containing up to 12 AMR genes in known BRD bacteria. Picking up an ICE can instantly turn a bacterium that is susceptible to all antibiotics into a multidrug resistant bacterium. Trueperella and Bibersteinia have been shown to carry ICE. So even if these bacteria aren’t major players in BRD, they may play a role in spreading antibiotic resistance to bacteria involved in BRD.
Objectives
- Isolate BRD pathogens Trueperella pyogenes, Bibersteinia trehalosi, and Mycoplasma bovis (Mb) from feedlot cattle respiratory samples at different production stages.
- Carry out antimicrobial susceptibility testing
- Study the possible risk factors associated with higher AMR in Mb at feedlot entry
- Genomic characterization of Trueperella and Bibersteinia and their association with AMR genes found in ICE elements
- Determine whether Trueperella and Bibersteinia can conjugate and trade ICE with more common BRD bacteria (Mannheimia, Histophilus and Pasteurella).
What they will do
This team will use samples collected from commercial feedlot cattle through the CIPARS feedlot surveillance program, as well as samples collected from healthy and sick (or dead) cattle at different stages of the feeding period from companion research projects. They will look for these “unknown” bacteria and see if they’re potentially playing a role in the spread of AMR in the feedlot population. They will also assess AMR in Mycoplasma (which is hard to culture and not examined in the CIPARS feedlot program).
Implications
These results will help inform diagnostic tests for antibiotic resistance as well as efforts to use CRISPR and other strategies to combat ICE transmission in other research projects.