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Name: Mary N.
Status: Other
Age: 20s
Location: N/A
Country: N/A
Date: 2001

How do the microbes in ruminants' rumen initially get there? Do the microbes come from the mother? From the feed?

Probably all: from the mother, from the feed, from faecal contamination of the grass...the gut of mammals is sterile at birth, but soon becomes colonized with micro-organisms. For humans the mother donates many species (this is true for mouth flora also), and the gut microflora goes through considerable changes during childhood, the most noticeable when a child changes from being breast-fed exclusively to other foods. Even in adults the gut microflora is not completely constant. Dietary and environmental changes (travelling, antibiotic use) can result in changes of the microflora composition but soon a 'healthy' balance is restored in most cases without trouble.

Trudy Wassenaar

Dear Mary,

A developing mammalian fetus is sterile, but is quickly exposed to bacterial flora @ birth. Colonization of the GI tract begins with the 1st milk feeding. So one could say that the bacteria are derived from the mother, but neonatally rather than pre-natally. The following web site from the Univ. of Wisconsin has a detailed discussion of the various bacterial flora:

The differences between humans & ruminants might be of particular interest.

Thank you for the good question,

Jeff Buzby, Ph.D.

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