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An in vivo poultry model to study the effect of growth promotors on resistance to human antibiotics in mixed bacterial - OD2001

This proposal has been formulated following the request by MAFF for research to establish an in vivo model with which to investigate the possible development of resistance to current and potential anti-microbials, resulting from the use of antimicrobial growth promoters, which are perceived by some experts as major contributors to the problem of human antibiotic resistance.

The project is designed, using chickens as an in vivo model, to determine (1) whether mixed intestinal bacterial populations including two main anaerobic groups (bacteroides and clostridia), and three faculatative anaerobic groups (lactobacilli, enterococci and E.coli) present innthe gut flora, will develop resistance to human antibiotics and (2) how any resistance to antibiotics is influences by either, inter-reaction between the bacterial groups, or by shifts in numbers or types within the bacterial populations in th chicken intestinal tract, following exposure to presently used growth promoters.

Although significant actions to reduce the commercial use of antimicrobial growth promoters have been made recently, there are still concerns about the use of current antimicrobial growth promoters, including the possibility of indirect hazard to humans form the persistence of such agents in poultry and other mear products. Consequently, the EC`s Scientific Steering Meeting Committee has identified four important areas where it proposes action should be taken: (1) prudent use of antimicrobials, (2) prevention of infection and containment of infective organisms, (3) alternative growth enhancers, and (4) monitoring the effect of any intervention.

The results of this proposal should provide clarification and a better understanding of the role ofgrowth promoters on the development of resistance to antibiotics, allowing MAFF and other, to make more factually based risk assessment decisions regarding their use.
01: To determine whether an antimicrobial agent, used at a sub-therapeutic level as a growth promoter, is associated with the development of patterns of resistance to human antibiotic agents amoung mixed bacterial populations, in chickens.

02: To determine whether the anitmicrobial agents are associated with shifts in the numbers of resistant strains within the bacterial groups.

03: To determine whether the antimicrobial agents are associated with shifts in the sub-groups of resistant strains within each of the bacterial groups.

04: To determine whther strains resistant to antibiotics, amy, or may not, be associated with the selective pressure excerted by antimicrobial agents.

05: To produce factual information on antimicrobial resistance in poultry due to the use of current growth promoters.
Project Documents
• Final Report : An in vivo poultry model to study the effect of growth promotors on resistance to human antibiotics in mixed bacterial   (10188k)
Time-Scale and Cost
From: 2000

To: 2003

Cost: £235,113
Contractor / Funded Organisations
University - Bristol
Animal Diseases              
Animal Health              
Antimicrobial Resistance              
E.coli O157              
Plants and Animals              
Fields of Study
Animal Health