Can We Simultaneously Reduce E. Coli Contamination and Methane Emissions by Manipulating the Rumen Microbiome of Beef Cattle?
Project Title
Novel Microbiome Manipulation Strategies for Reducing Methane Emission and Foodborne Pathogen Colonization
Researchers
Dr. Leluo Guan - University of Alberta lguan@ualberta.ca
Dr. Tim McAllister, Agriculture and Agri-Food Canada; Dr. Mi Zhou, University of Alberta
| Status | Project Code |
|---|---|
| In progress. Results expected in March, 2028 | FDE.19.21 |
Background
Two concerns with beef production commonly raised by consumers are methane emissions and food-borne pathogens that can lead to illness in humans, such as E. coli. Neither methane emissions or E. coli prevalence have an effective long-term solution but both have roots in the makeup of the rumen microbiome. These researchers want to study the genetic makeup of rumen microbes to determine how they play a role in methane production and the presence of e. coli and if a mitigation process can be developed.
Objectives
- To develop RNA interference (RNAi)-based method to lower enteric CH4 production from key methanogens.
- To evaluate how effective the microbial manipulation methods are for methanogens using an artificial rumen (RUSITEC).
- To use a CRISPR-cas-based method to lower STEC population in the gastrointestinal tract (GIT).
- If positive results are shown in the described in vitro experiments, to test the efficacy of the method on lowering CH4 emissions and STEC load in the GIT in vivo.
What they will do
The genome for E. coli 0157 and the genomes of key methanogen species in the rumen have previously been sequenced and will be used for searching RNAi targets. This team will use gene editing techniques to target specific genes that are known to be able to be manipulated. The top 3 will then be used in manipulation experiments. Researchers will use gene editing to target manipulate the bacteria genes and will verify if this has an effect on methane or E. coli in a lab setting and methane emissions using the RUSITEC.
If the artificial rumen studies work, it will be tested in vivo on 40 grazing heifers. Researchers will then collect rumen fluid and fecal samples from 40 cows/heifers grazing on three different types of pasture or in a feedlot. They will then examine the previously determined candidate genes and the level of expression of those genes.
Implications
This project is a long way from developing tools that can be used on farm but if this can be done we are one step closer to one time strategies with long lasting effects that can both reduce methane emissions in cattle and/or reduce E.coli contamination of beef products.
The long-term goal is to develop an effective system that allows precise microbial manipulation for farm animals, without interfering with the other gut microbes and their functions. This approach is expected to be more precise, effective, consistent, and cost-wise, and to be able to be applied to different regions, management systems and ruminant species.