Determine the impact of antimicrobial residues on the human intestinal microbiota using "omics" and analytical chemistry methods. These studies will evaluate metabolism and inactivation of antimicrobial drugs by gastrointestinal bacteria which may impact the effectiveness of these agents at their intended target sites. DM performs methods to assess risks to the gastrointestinal microflora of humans when antimicrobial compounds are ingested in food residues, probiotics and dietary supplements. Understanding the impact of antimicrobial residues on the human intestinal microbiota will provide a new tool in determining acceptable daily-intake limits of antibiotic residues. Data from these studies is being used by CVM to evaluate the safety of veterinary drugs in foods of animal origin. In addition, Division of Microbiology/NCTR scientists are actively providing guidance to CVM, WHO and VICH - International Cooperation on Harmonization of Technical Requirements for Registration of Veterinary Medical Products concerning specific methodologies used to determine if the ingestion of residues of antimicrobial agents in food impact the health of the consumer. ON TRACK ON TRACK main 1. Develop analytical chemistry and bioassay methods to detect veterinary drugs or metabolites in complex matrices 4/30/2010 Completed 4/30/2010 main 2. Start fecal collection from human subjects to determine the impact of drug residues on human intestinal microbiota 5/31/2010 Completed 5/31/2010 main 3. Develop molecular based "omics" methods to determine composition of human intestinal microbiota affected by veterinary drug exposure 9/30/2010 <i>(6/30/2011)</i> Completed 6/30/2011 main 4. Complete the assessment of research findings 9/30/2011 Completed 9/30/2011 main 5. Develop draft technical report/manuscript/publication 3/31/2012 <i>(5/31/2013)</i> On Track main 6. Complete the peer review (NCTR and other researchers) of draft technical report, manuscript, and/or publication 3/31/2012 <i>(5/31/2013)</i> On Track main 7. Obtain NCTR Center Director approval on the draft technical report, manuscript, and/or publication via the document tracking system 5/31/2012 <i>(9/30/2013)</i> On Track main 8. Submit final technical report, manuscript, and/or publication on human intestinal microbiota to a scientific journal 5/31/2012 <i>(9/30/2013)</i> On Track WHO World Health Organization VICH Veterinarian International Conference on Harmonization bioassay methods experiment to determine the effect of a substance on an organism http://www.fda.gov/AboutFDA/Transparency/track/ucm203296.htm FDA-TRACK NCTR Dashboard http://www.fda.gov/AboutFDA/Transparency/track/ucm252974.htm FDA-TRACK Research Glossary ਍††਍਍਍਍਍਍਍