A rapid, reliable method for the extraction from avian faeces of total bacterial DNA to be used as a template for the detection of antibiotic resistance genes

Abstract

Sir, Recent reports, for example that published by the House of Lords, have highlighted concern over the role played by antibiotics added to animal feedstuffs in antimicrobial resistance of human pathogens. It has been established for some time that the use of antibiotics in animal feedstuffs leads to the selection of antibiotic-resistant bacteria. It has been found that resistance persists after the antibiotic has been withdrawn. Furthermore, the mobility of antibiotic resistance determinants has been highlighted by the discovery of resistance in animal rearing facilities that did not use antibiotics in feedstuffs. Concern over the scale of this problem has resulted in Sweden banning the use of all antibiotics in feedstuffs and to the European Union banning the use of avoparcin, bacitracin zinc, spiramycin, tylosin phosphate and virginiamycin in animal feedstuffs. Most concern about antimicrobial resistance has focused on the enteric bacteria, mainly Escherichia coli and salmonellae, since they are recognized human pathogens. The bowel microflora is diverse, however, and, in addition to pathogens, contains species that may harbour transferable antibiotic resistance determinants, some of which may be non-cultivable. These bacteria thus act as a silent gene pool for the potential dissemination of antibiotic resistance determinants. The most appropriate way to study the occurCorrespondence Journal of Antimicrobial Chemotherapy (2001) 47, 239–246