ARS | Publication request: FERMENTATION OF 14C-LABELED AMINO ACIDS BY BATCH CULTURES OF A CHARACTERIZED CONTINUOUS-FLOW (CF3) COMPETITIVE EXCLUSION CULTURE OF BROILER CECAL BACTERIA

Submitted to: Poultry Science Association Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: May 19, 1996
Publication Date: N/A

Technical Abstract: Competition for growth-limiting nutrients by broiler cecal bacteria and Salmonella has been suggested as one of several factors associated with the reduction of Salmonella cecal colonization. The amino acids arginine, aspartic acid, serine, and threonine have been indicated as Salmonella growth-limiting nutrients. Increases in the concentrations of broiler cecal lactic acid and volatile fatty acids (VFA), mainly acetic, propionic, and butyric, are additional factors associated with reduced Salmonella cecal colonization. In the present study, culture media containing either unlabeled arginine, aspartic acid, serine, or threonine were inoculated with a continuous-flow culture (CF3) of competitive exclusion broiler cecal bacteria and then were incubated anaerobically as batch cultures. 14C-arginine, 14C-aspartic acid, 14C-serine or 14C- threonine, respectively, were added to the cultures at various times after inoculation and cultures were incubated further. Concentrations (umol/ml) of unlabeled acetic, propionic, and butyric acids at the end of incubation were, respectively: 27.9, 34.6, and 16.0 in arginine cultures; 38.4, 55.4, and 14.6 in aspartic cultures; 42.9, 35.7, 18.1 in serine cultures; and 20.1, 47.4, and 21.8 in threonine cultures. Percentages of detected 14C distributed among VFA, and unknown fermentation products were, respectively: 0, 100, 0, and 0 in arginine cultures; 11.1, 84.6, 2.1, and 1.1 (with 1.1% in lactic acid) in aspartic cultures; 56.3, 22.5, 21.2, and 0.0 in serine cultures; and 3.4, 67.9, 16.4, and 12.3 in threonine cultures. Results from this study indicated that the Salmonella growth- limiting amino acids arginine, aspartic acid, serine, and threonine were metabolized by CF3 competitive exclusion broiler cecal bacteria to VFA.