as you know understanding the interactions between hydrogen producers and consumers in the rumen ecosystem is important for ruminant production and methane mitigation.

some experiments show the absence of protozoa may affect differently the methanogen community and methane emissions in wethers.

for more information , you can see : Br J Nutr. 2012 Feb;107(3):388-97. doi: 10.1017/S0007114511002935. Epub 2011 Jul 18.

The british journal of nutrition: Rumen protozoa and methanogenesis: not a simple cause-effect relationship.

Hi Mohamad

I think these 3 papers can help you.