Antimicrobial growth promoter use in livestock-implications for human health

The use of antimicrobial growth promotants began in the 1940s and continues in much of the world today. In the USA, the majority of antimicrobial use is dedicated to growth promotion in feed animals. Use of glycopeptides, tetracyclines, streptothricins, macrolides, and streptogramins for livestock growth promotion has been associated with selection of drug resistant bacteria. The selection of antimicrobial resistance in livestock has been associated with antimicrobial resistance in bacteria causing human disease. This threat to human health has led to recommendations from many experts to limit the use of antimicrobial agents for the purposes of growth promotion in animals. Such recommendations have effected large-scale livestock health policy changes in some parts of the world, although the USA has enacted few policy changes regarding the use of antimicrobial growth promotants.