The use of antimicrobial agents in broiler chickens

•Antimicrobial agents are essential tools for treating and controlling bacterial infections in poultry.•Proper use of antimicrobials depends on knowledge of the interrelationships between bacteria, antimicrobial and host animal.•The pharmacotherapeutic characteristics of commonly used antimicrobial agents in broiler chickens are reviewed.•Anatomical–physiological features of poultry are reviewed with regard to drug disposition. Antimicrobial agents are essential tools for treating and controlling bacterial infections in poultry production. Veterinarians have a huge responsibility when using antimicrobials in poultry producing meat and eggs for human consumption. The term ‘judicious use’ of antimicrobials implies the optimal selection of drug, dose and duration of antimicrobial treatment, along with a reduction in inappropriate and excessive use as a means of slowing the emergence of antimicrobial resistance. The proper use of antimicrobials depends on the knowledge of interrelationships between bacteria, antimicrobial, host and consumer. This article reviews the anatomical–physiological features of poultry relating to drug disposition as well as the pharmacological and therapeutic characteristics of the most commonly used antimicrobials in broiler chickens. Doses frequently employed for flock treatment are presented as are accepted withdrawal times.