CECAL PROPIONIC-ACID AS A BIOLOGICAL INDICATOR OF THE EARLY ESTABLISHMENT OF A MICROBIAL ECOSYSTEM INHIBITORY TO SALMONELLA IN CHICKS

Experiments were conducted to evaluate the effects of different compet itive exclusion (CE) cultures on the concentration of cecal propionic acid in 3-day-old broiler chicks, and the correlation between cecal pr opionic acid concentration and protection against Salmonella colonizat ion. CE cultures that significantly (P < 0.05) increased cecal propion ic acid in 3-day-old chicks decreased (P < 0.05) cecal Salmonella colo nization in 10-day-old chicks compared with the untreated controls. CE cultures that failed to significantly (P > 0.05) increase cecal propi onic acid concentrations in 3-day-old chicks failed to protect (P > 0. 05) against cecal Salmonella colonization in 10-day-old chicks compare d with untreated controls. A significant (P < .05) correlation (-.88) was found between cecal propionic acid concentration in 3-day-old chic ks and cecal Salmonella colonization in 10-day-old chicks. (C) 1996 Ac ademic Press.