An antimicrobial is a substance that either kills (microbiocidal) or inhibits (microbiostatic) the growth of micro-organisms such as bacteria, fungi, or protozoans.

Disinfectants are antimicrobial substances used on non-living objects or outside the body.

Veterinary surgeons prescribe antimicrobials for treatment and control of disease in pigs. These may be administered in feed, in water or by injection.

The emergence of antimicrobial resistance as a serious problem in human medicine has prompted concerns that resistance or resistant bacteria could be transferred from livestock to the human population (and vice versa). The effectiveness of some medical antimicrobial treatments might be compromised if this occurred. Research reported in 2011, however, suggested that the animal population is unlikely to be the major source of antibiotic resistance in humans.

In the EU the use of antimicrobials in animal feed as growth promoters has been banned since 1 January 2006.

The EU ban of antimicrobials in 2006 aimed to reduce the general use of antibiotics in farmed animals.

After the removal of AGPs in pig diets few problems were however seen in finishing pigs. Some problems were seen in young, weaned piglets, which were susceptible to gut health problems.

This lead to producers having to review their basic management strategies, in particularly to reduce any risks factors that could trigger health issues in the weaned piglets.

Copper was used in the past as a growth promoter in pigs. However, in 2003, the limit for copper inclusion in diets was reduced, meaning that the level of copper inclusion currently allowed does not have a growth–promoting effect.

Zinc oxide can be prescribed by a veterinary surgeon to treat enteric health issues. Although legal the individual producer should aim not to use zinc oxide as a long term solution – to reduce the potential heavy metal loading and contamination of the environment.

Antimicrobials should be used responsibly.

May 2012