FECAL BILE-ACIDS AND NEUTRAL STEROLS IN THE COTTON-TOP TAMARIN (SAGUINUS-OEDIPUS)

1. The cotton-top tamarin (Saguinus oedipus), a small New World primate susceptible to spontaneous development of colon cancer, was studied for its fecal neutral sterol and bile salt composition. 2. Standardization procedures to establish the effect of exposure of the stool to room temperature air for various time-periods showed no significant effects on the neutral sterol and bile salt composition of the samples. 3. Microbial degradation of cholesterol and bile acids to secondary metabolites showed a progressive rise during the first year of life after which some degree of homeostasis was observed. 4. The proportion of cholesterol that remained unmetabolized by colonic microflora was in excess of 50%, an amount that was significantly higher than in man and other higher primates. 5. Ursodeoxycholic acid was identified as a significant (12%) component of fecal bile acids in this species. 6. Secondary bile acids formed by the action of enteric microflora were also significantly lower than levels found in man and other animals.