<p>Methanogens belong to a group of ancient microbes known as archaea. They have evolved hundreds of millions of years ago and occupy oxygen-free niches such as peat bogs and anaerobic gut systems.</p>
<p>In the rumen, methanogens modify the fermentation process, but they are not thought&nbsp;to be essential to the host animal. They are opportunists, taking advantage of one of the by-products of fermentation in the rumen: hydrogen gas. This provides an energy source<br />and methanogens combine it with carbon dioxide to produce methane and water. The methane is released into the atmosphere when the animal belches. The methanogens&rsquo; use of hydrogen represents a loss of dietary energy to the animal. The small blue cells in the image below methanogen cells in the gut contents of a sheep.&nbsp;</p>
<p><img class="" title="p16_methanogen.jpg" src="user/image/medium/550/p16_methanogen.jpg" alt="p16_methanogen.jpg" data-href="" /></p>
<p>Read more about enteric fermentation</p>
<p>Read more about NZ methane mitigation research</p>