Intestinal microflora of Macaca fascicularis fed with commercial pellets was studied. The monkeys were grown and bred in a controlled condition followed by being divided into five groups according to their age.
Total counts of microbes were around 10¹⁰/g-feces in four groups ranging from group A (0.5-1 year old), group B (2-3 years old), group C (4-5 years old) to group D (6 years old). However, a slight decrease in the counts (10^9.7/g-feces) was observed in group E (over 10 years old).
In general, Enterobacteriaceae, Streetococcus, Eubacterium and Bacteraidaceae were always predominant in all groups. In group A, major microbes were Bacteroidaceae, Eubacterium and Bifidobacterium which constituted almost 90% of total counts. In group B, Streptococcus was the most predominant species along with Eubacterium and Bacteroidaceae. Constitution of microflora in group C was almost the same as group B except for an increase in Streptococcus. In group D, Eubacterium and Bacteroidaceae increased again, with a decrease of Streptococcus, so that this group was different from group B or C. Group E was unique in which Streptococcus and Megasphaera were the least as compared with other groups, and Eubacterium and Bacteroidaceae remained predominant.
In view of the changes in the intestinal microflora, the monkeys are classified into four groups, namely 0.5-1 year old, 2-5 years old, 6 years old and over 10 years old of age groups.
It was concluded that Macaca fascicularis was a comparable animal to human in the nutritional and metabolic studies.