Effects of diet on the gastric papiDae and microflora of the rodents Mystro'!'ys albicaudatus and Cricetomys gambiluuls

Abstract

Diets high in soluble sugar concentration cause an increase in number and hypertrophy of gastric papillae, and a dominance of filamentous bacilli in the asSOCiated symbiotic mlcroflora in two species of rodent. Fibrous diets do not stimulate the growth of papillae but trigger a change in the microbial community which becomes dominated by cocci. Intermediate diets are associated with regular papillae and a mixed gastric microflora The results support an amylolytic reservoir, rather than a cellulose fermentation hypothesis for the symbiosis. The responses of C. gambianus (and its microflora) are more complex than those of M. albicaudatus which suggest multiple functions, including the possible detoxification of secondary plant compounds. Protein digestion and amino acid requirements require urgent attention. The rodent-bacteria symbiosis has important consequences for nutritional niche definition and the competition and coexistence of herbivores.

S. Afr. J. Zool. 1987, 22(2)