DOROTA ROSZAK1, MIROSŁAWA GAŁĘCKA2, WOJCIECH CICHY1 and PATRYCJA SZACHTA2* 1First Department of Pediatrics; Department of Pediatric Gastroenterology and Metabolic Diseases, Poznan University of Medical Sciences, Poland 2Institute of Microecology, Poznan, Poland *Corresponding author: P. Szachta, Institute of Microecology, Poznan, Poland; e-mail: patrycja_szachta@o2.pl. ...