Expert: Chris Larsen - 1/5/2011

Question
Where do I go to find information on the amount of bacteria in herbivores and omnivores such as a dog, human, guinea pig, and horse?

Answer
Hi Grace,

Thanks for the question!  

Here is a fantastic link to the normal bacterial flora of humans (specifically look at Table 1):

http://www.textbookofbacteriology.net/normalflora.html

With respect to dogs:

The Procter & Gamble Company conducted research on dental bacteria in dogs' oral cavities by isolating bacteria from plaque and saliva. The bacterial genera most frequently found in dogs' saliva were identified as actinomyces, streptococcus and granulicatella; in the plaque, the types of bacteria included porphyromonas denticanis, actinomyces and neisseria. The results showed that "cultivable canine oral microbiota is mainly composed of species distinct from those found in humans," plus the dog plaque was characterized by a low number of streptococci.

Source:  http://www.ehow.com/list_6568566_types-bacteria-dog_s-mouth.html

With respect to horses:

The normal flora of the horse's mouth is quite extensive.  Here is a study that was done on the normal flora of the mouth and nose of a normal horse:

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC378793/pdf/jbacter01078-0072.pdf

I can't seem to find any definitive, up to date information about the normal flora of the guinea pig.

Hope this helps!

-Chris