How can antibiotic use in animal farming contribute to antibiotic-resistant bacteria?

In intensive animal farming, the routine administration of antibiotics to healthy animals—often for growth promotion or prophylactic disease prevention—is a primary driver of antibiotic resistance.1

Because these farms are dense environments where pathogens thrive, the widespread use of low-dose antibiotics creates selective pressure that encourages the survival and proliferation of resistant bacterial strains. These bacteria can then spread beyond the farm through manure used as fertilizer, contaminating soil and entering the broader environment.1

This practice poses a significant ethical and public health concern, as it threatens the efficacy of essential medicines used in both veterinary medicine and human healthcare. The World Health Organization has explicitly identified antimicrobial resistance as a serious threat to global public health and advocates for strictly limiting the use of medically important antibiotics in food animals to only those cases where a bacterial disease has been clinically diagnosed.1