Globally, around 32 percent of global human-induced methane emissions come from livestock, mainly from enteric fermentation and manure management systems. Recent meta-analysis identified that the main intervention to reduce enteric methane production is by direct impacting methanogenic Archaea in the rumen that produce it. Vaccines offer a great potential since they don’t require direct and frequent access to the animals.

However, with vaccination, we are faced with diverse problems, the main one being our lack of understanding if and how rumen microorganisms, and more specifically methanogenic archaea, are detected and potentially controlled by the immune system of the animal. The rumen and the large intestine of ruminants are quickly colonized during and after birth by methanogenic archaea and the processes occurring during this colonization over the first weeks of life are critical to understand their recognition by the developing immune system of the animal. This major gap of knowledge needs to be closed before we can fully develop an immunization strategy.

Challenge       

The rumen and the large intestine of ruminants are quickly colonized during and after birth by methanogenic archaea until the animal is weaned and the rumen is developed. The processes occurring during this narrow window of time (6-8 weeks) in development of the gastro-intestinal tract are characterized by a great plasticity and define whether the microbiome is tolerated by the developing immune system.

Therefore, our hypothesis is that methanogens colonise the developing rumen so early after birth that they are either tolerated by the innate immune system or not detected by the immune system due to their location. As the rumen is an immunological “inert” organ, compared to the caecum where methanogens also establish, we must understand how we can either prevent the rumen from being colonised by Archaea, not to the detriment of the animal, or how we can stimulate an immune response against Archaea.

Our aim is to understand how methanogens either avoid immune recognition or manipulate the immune system to avoid detection, and subsequently to use this knowledge to develop a blueprint for an “immunogenic methanogen” that will enhance vaccine responses. Obtaining funding from philanthropy is key to establishing a strong and effective scientific collaboration between animal scientists, rumen microbiologists and immunologists to eventually provide a proof of concept (together with proposal from Pirbright Institute) before a global methane vaccine initiative can be developed.

Partners      

Dr David Yanez-Ruiz (https://www.eez.csic.es/)

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