Use of antimicrobial drugs in veterinary practice

Summary points Antimicrobial drugs are used by veterinary surgeons for pet and farm animals in their care Veterinary use of antimicrobial agents is for therapeutic and prophylactic reasons, and they may be used to promote growth Antimicrobial agents are more often given intramuscularly to animals compared with humans They are also given to groups of animals in food or water Antimicrobial drugs may be given to animals reared for food only if they are licensed for that purpose Withdrawal periods are specified for antimicrobial drugs used in animals reared for food, and there is regular monitoring for drug residues Treatment of farm animals The prevalence of pathogens on farms depends on many factors, not least the type of husbandry, the environmental pressure on a farm, and the standard of stockmanship. A special form of prevention is called metaphylaxis, in which all animals in the herd or group are treated when the proportion of animals that has become diseased during a defined period and the probability of most or all of them getting infected are high. 7 Diseases requiring the most extensive use of antimicrobial drugs for treatment or prophylaxis are respiratory and enteric diseases in pigs and cattle and mastitis in dairy cattle. 7 8 Fish that are reared intensively have special requirements as any infection may lead quickly to an acute outbreak of disease in a cage or pond.