RESUMO
The presence of ampicillin-resistant Escherichia coli (Amp(r) E. coli) in the fecal flora of calves was monitored on a monthly basis in seven cohorts of calves. Calves were rapidly colonized by Amp(r) E. coli, with peak prevalence in cohort calves observed in the 4 months after the calves were born. The prevalence of calves yielding Amp(r) E. coli in cohorts consistently declined to low levels with increasing age of the calves (P < 0.001).
Assuntos
Envelhecimento , Resistência a Ampicilina , Portador Sadio/veterinária , Doenças dos Bovinos/microbiologia , Escherichia coli/isolamento & purificação , Fezes/microbiologia , Animais , Portador Sadio/microbiologia , Bovinos , Escherichia coli/efeitos dos fármacos , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/veterinária , Resistência às PenicilinasRESUMO
The emergence of antimicrobial-resistant microorganisms in both humans and food animals is a growing concern. Debate has centred on links between antimicrobial use in the production of food animals and the emergence of resistant organisms in the human population. Consequently, microbial risk assessment (MRA) is being used to facilitate scientific investigations of the risks related to the food chain, including quantification of uncertainty and prioritization of control strategies. MRA is a scientific tool that can be used to evaluate the level of exposure and the subsequent risk to human health relating to a specific organism or particular type of resistance. This paper reviews the recent applications of MRA in the area of antimicrobial resistance, and in particular, it focuses on the methods, assumptions and data limitations. Since MRA outputs are dependent on the quality of data inputs used in their development, we aim to promote the generation of good quality data by describing the properties that data should ideally possess for MRA and by highlighting the benefit of data generation specifically for inclusion in MRAs.