Comparison of Batch Culture Growth and Fermentation of a PoultryVeillonellaIsolate and SelectedVeillonellaSpecies Grown in a Defined Medium

Abstract

The objective of this study was to develop a defined medium for quantitating nutritional requirements and fermentation products of a poultry cecal isolate ofVeillonellaand to compare these parameters with representativeVeillonellaspecies. The poultry isolate is one of 29 organisms from a continuous-flow culture that has been shown to be effective againstSalmonellacolonization in broilers. When theVeillonellaspecies were grown in anaerobic batch culture, propionate and acetate were the only volatile fatty acids detected. Lactate was needed to provide energy for the growth of theVeillonellain the defined medium. The poultry isolate had significantly (p< 0.05) higher Ylactate(g of dry cell weight per mole of lactate utilized) and dry cell weight than the otherVeillonellaspecies when grown on amino acid supplemented defined media. Cultures of theVeillonellaspecies in the defined medium grown with supplemented amino acids aspartate, threonine, arginine, and serine indicated that these amino acids were metabolized to acetate and propionate. Amino acid analysis on media inoculated with eitherV. atypicaor the poultry isolate also indicated that these organisms may have different amino acid preferences. For nearly all of the amino acid supplemented media combinations the poultry isolate utilized significantly (p< 0.05) more threonine and serine whereasV. atypicautilized significantly (p< 0.05) more aspartate. The defined medium supported growth of all of theVeillonellaspecies tested and should enable further in-depth physiological studies to be conducted on the poultryVeillonellastudies.