MICROENVIRONMENT INFLUENCES THE PATTERN OF BACTERIAL TRANSLOCATION INFORMULA-FED NEONATES

The authors previously demonstrated that neonatal rabbits fed conventi onal formula have a significantly greater incidence of bacterial trans location than do neonatal rabbits fed breast milk. They hypothesized t hat exogenous bacteria in the formula and/or the microenvironment of t he neonatal rabbit may contribute to the higher incidence of bacterial translocation. In the present study, the authors examined the inciden ce of bacterial translocation in neonatal rabbits fed pasteurized form ula, unsterile formula, or breast milk while being housed in a clean o r unsterile environment. The rabbits were divided into five groups. Gr oups I and II were fed pasteurized formula; groups ill and IV were fed unsterile formula. In addition, groups I and III were housed in a cle an environment, and groups II and IV were kept in an unsterile environ ment, The neonates in group V were fed breast milk and were kept in an unsterile environment. On the seventh day, the animals were killed, a nd the mesenteric lymph nodes, liver, and spleen were cultured for the presence of bacteria, Bacterial translocation occurred in 100% of gro up IV neonates. A clean environment (groups I and III) eliminated gram -negative bacterial translocation. A reduction (50%) in the overall in cidence of bacterial translocation was obtained by pasteurizing the fo rmula (group I v group III). Group II had significantly less gram-nega tive bacterial translocation than did group IV. None of the neonates i n group V had translocation. The data show that a clean environment ab rogates gram-negative bacterial translocation. Pasteurizing the formul a significantly reduces the incidence of gram-negative bacterial trans location, and further reduces overall bacterial translocation in a cle an environment. The authors hypothesize that control of the microenvir onment can significantly influence the pattern of bacterial translocat ion in formula-fed neonates, and thus potentially reduce the incidence of gut-origin sepsis. Factors present in breast milk inhibit bacteria l translocation, regardless of the microenvironment. (C) 1996 by W.B. Saunders Company