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In Vitro Model and Molecular Analysis of Competitive Exclusion Products

Wagner, Robert
DHHS/FDA - National Center for Toxicological Research
1) To evaluate individual component bacteria in a defined competitive exclusion (CE) product for exclusion of enteric pathogens from Caco-2 and CRL-2117 cell monolayers. 2) To define the antimicrobial susceptibility patterns of the component bacteria using Minimal Inhibitory concentration measurements.3) To sequence analysis of 16s rRNA polymerase chain reaction (PCR) products from defined culture component bacteria and development of a database containing the sequeces for use in subsequent identification of the organisms in undefined CE products. 4) To apply the 16s rRNA sequence analysis procedure to detect and identify effective CE component bacteria in undefined CE products.
More information
FY 2000 Accomplishments:
  1. Completed in vitro essay of competitive exclusion products.
  2. Identified 18 of 27 bacterial isolates from Preempt by multiple phenotypic and genotypic techniques.
  3. Evaluated 18 0f 27 MIC analyses from Preempt isolates.
FY 2001 Plans:
  1. Complete the objectives and send results to CVM for review.
  2. Propose a new project of antibiotic residue effects on colonization resistance.
  3. Propose an in vivo assay of probiotic effects on host defense.
Funding Source
Nat'l. Center For Toxicological Research
Project number
Chemical Contaminants
Veterinary Drug Residues
Antimicrobial Resistance