Modulation of the rumen microbiome by bacteriocins: impact on methane emission reduction and improvement of key physiological functions of the rumen

The reduction of greenhouse gas (GHG) emissions has become a global concern due to the environmental and population risks it poses worldwide. Initiatives have been launched across the globe to mitigate GHG emissions at the source, contributing to the collective effort to reduce the risks of climate change on our planet. Quebec is no exception and has committed to this initiative by adopting its "Plan for a Green Economy 2050." Among the economic sectors targeted by this plan, the dairy sector, one of the largest contributors to GHG emissions, has been specifically identified.

Thus, reducing methane emissions from ruminants has become a priority for the sector, with the goal of cutting these emissions and achieving carbon neutrality in milk within the coming years.

This research project is fully aligned with Quebec's efforts to reduce GHG emissions in the dairy sector and to achieve carbon-neutral milk by 2050. A mixed approach will be adopted, including metagenomics, metabolomics, and physiology, to study and characterize the potential of various bacteriocins from lactic acid bacteria to positively modulate the rumen microbiome of dairy cattle. The project aims not only to reduce enteric methane production during ruminal fermentation but also to improve feed conversion and energy efficiency in dairy cattle.

The originality of our approach lies not only in using a consortium of bacteriocins as natural antimicrobials to reduce methane production by methanogenic microorganisms but also in studying the impacts on the ruminal ecosystem as a complex biological entity, taking into account all microbial communities present and the main functional physiological characteristics of the rumen.

Natural products based on well-characterized bacteriocins will be developed. Their effectiveness will be demonstrated both in vitro and in vivo in dairy cattle. The expertise of the project team in dairy cattle nutrition and management, GHG management, digestive physiology, and large-scale bacteriocin production, along with the successful history of using and approving bacteriocins in various sectors, will guide these efforts toward commercial exploitation in the dairy industry. Therefore, the project will address several priority research themes in Novalait's production.

It is also perfectly aligned with the activities of the "Living Laboratory - Carbon Neutral Milk" project recently initiated by the Quebec Milk Producers.