INFLUENCE OF 2 INFANT FORMULAS AND HUMAN-MILK ON THE DEVELOPMENT OF THE FECAL FLORA IN NEWBORN-INFANTS

The establishment of the faecal flora of 39 full-term infants fed excl usively on breast milk (n = 20) or with two different modern adapted c ow's milk formulas (n = 19) was studied during the first 3 months of l ife. One formula investigated was based on 100% bovine casein as the p rotein source whereas the other formula contained bovine milk proteins with a whey/casein ratio of 60:40. A faecal flora rich in bifidobacte ria was found in all study groups; the growth of putrefactive bacteria (especially Bacteroides spp.), however, was limited. In formula-fed i nfants, significantly higher bacterial counts of enterococci and clost ridia were detected compared to breast milk-fed infants. Similarities and differences due to the feeding regimen were particularly reflected in the pattern of the anaerobic bacterial species. Bifido-bacterium b ifidum, B. infantis and B. breve constituted the majority of the bifid obacterial flora independent of the type of milk feeding. Other bifido bacterial species such as B. longum, B. adolescentis, B. parabifidum a nd B. pseudo-catenulatum were detected in high numbers and at low freq uencies in breastfed infants. The latter three were observed in infant s fed the whey/casein formula as well. It seems that infants fed a cas ein formula develop a faecal flora more like that of breastfed infants concerning Lactobacillus spp. (especially L. fermentum and L. brevis) .