1 Use of antimicrobials in animal health
1.1 Purposes of antimicrobial use in food animals
Antimicrobials have been used in animals for almost as long as they have been available to people. They have revolutionised our approach to the treatment and prevention of diseases and have brought considerable benefits to people and animals by:
- alleviating pain and suffering
- ensuring food security
- protecting livelihoods
- reducing zoonotic disease spread.
However, as antimicrobial resistance (AMR) continues to threaten public health, much attention has focused on the use of antimicrobials in food animals. This is because many of the same antimicrobials used in animals are also used in human health. A major concern to many people is antimicrobials being used for growth promotion, where sub-therapeutic doses are administered to increase productivity. We’ll discuss critically important antimicrobials (CIAs) being used in animals and antimicrobials for growth promotion later in the module.
Antimicrobials are used in food animals for a range of purposes, which broadly fall into two categories: therapeutic uses to control diseases and non-therapeutic uses (Figure 1). In the following sections, we will review these purposes in more detail.

Figure 1 Purposes of antimicrobial use in food animals (OIE, 2017) Show description|Hide descriptionAn infographic of word boxes grouped to show the therapeutic and non-therapeutic uses of antimicrobials. Therapeutic uses are grouped under a heading ‘Relating to disease and under veterinary supervision’ and include treatment, control and prevention of disease. These are separated by a vertical broken line from non-therapeutic uses of which growth promotion sits under a heading ‘Relating to production’. It is important to understand when it is necessary and appropriate to use antimicrobials and when it is not.
Figure 1 Purposes of antimicrobial use in food animals (OIE, 2017) Veterinarians are qualified and registered or licensed by a government veterinary statutory body to practise veterinary medicine (or veterinary science) in the country in which they are registered. In almost all countries, veterinarians are responsible for prescribing antimicrobials for use in animals.
Veterinary paraprofessionals are authorised by a government veterinary statutory body to carry out designated tasks under the responsibility and direction of a veterinarian. Examples of veterinary paraprofessionals includes veterinary nurses, technicians, laboratory staff, and animal health and public health workers. The role of the veterinary paraprofessional in animal health is critically important in countries where there are few veterinarians. The OIE has published guidelines on veterinary paraprofessionals which you can review the OIE website [Tip: hold Ctrl and click a link to open it in a new tab. (Hide tip)] when appropriate.