Sequence of rumen development of the microbial ecosystem

In the newborn ruminant, the rumen is quickly colonized with specific micro-organisms.
The colonization of the rumen follows a very precise sequence:

• Anaerobic bacteria appear several hours after birth,
• cellulolytic bacteria and methanogenic archaea at 2-4 days of age,
• anaerobic fungi colonize the rumen during the second week,
• and ciliate protozoa begin to be established only during the third week.

The microbial contamination of the newborn’s rumen comes mainly from microorganisms present in the mother’s saliva and therefore requires very close and repeated contact between the newborn and its mother during the first few weeks of life. When the microbial ecosystem is stabilized, the young ruminant is ready to digest solid feed.

It is now understood that the microbial inbalances which can cause diarrhea can come from not only the intestine, but also from the rumen.

Animation of microbial consortium