The aim of our systematic literature review was to evaluate current knowledge on the effect of orally administered antimicrobials on AMR selection in E. coli from chickens. Our hypotheses were that
1)
oral administration of antimicrobials increases the rate of AMR in E. coli from chickens compared to
a)
no administration or
b)
the AMR rate before the administration of antimicrobial agents. (Effect of oral application of antimicrobials)
2)
the prevalence of AMR in E. coli is related to the number of different antimicrobials used. (Effect of the administration of more than one antimicrobial)
3)
underdosing of orally administered antimicrobial agents increases the probability of AMR in E. coli from chickens.