Microbiota profile in feces of breast- and formula-fed newborns by using fluorescence in situ hybridization (FISH).

The development of the gut is controlled and modulated by different interacting mechanisms such as, genetic endowment, intrinsic biological regulatory functions, environment influences and last but no least, the diet influence. Considered together with other endogenous and exogenous factors the type of feeding may interfere greatly in the regulation of the intestinal microbiota. During the last years molecular methods offer a complementarity to the classic culture-based knowledge. FISH has been applied for molecular evaluation of the microbiota in newborns delivered by vaginal delivery. Eleven probes/probe combinations for specific groups of faecal bacteria were used to determine the bacterial composition in faecal samples of newborns infants under different types of feeding. Breast-fed infants harbor a fecal microbiota by more than two times increased in numbers of Bifidobacterium cells when compared to formula-fed infants. After formula-feeding, Atopobium was found in significant counts and the numbers of Bifidobacterium dropped followed by increasing numbers in Bacteroides population. Moreover, under formula feeding the infants microbiota was more diverse.