The use of veterinary medicines may lead to risks concerning human health, environment, food safety, animal health and animal welfare. For example the use of antibiotics leads to the development of resistance in bacteria. The major determinant for resistance development is selection pressure on the bacterial flora by antibiotic usage. In food-producing animals in intensive animal husbandry systems, a large proportion of antibiotics is administered as group medication in feed. In this respect ‘feed' is a general term for routes of oral administration which includes water, milk(replacer), feed as premix and feed as topdressing. In The Netherlands 90% of the sales figures of antibiotics for therapy of the Federation of Veterinary Pharmaceutical Industries (FIDIN) is reported to be in feed medication. The therapeutic veterinary antibiotic use (including antimicrobial growth promoters) has increased in the period 1999-2007 by 83% and the growth promoters have been banned, first partly and as from 2006 entirely. The use increased by 8.9% in 2007 as compared to 2006 and in 2008 it decreased again by 12%. The therapeutic antibiotic use per kg live weight in 2007 was twice as high as in 1999. A part of this increase may be accounted for by a substitution of growth promoters.

In comparison with other countries for which veterinary antibiotic consumption figures are available, the antibiotic use per average food-producing animal is greatest in the Netherlands . However, it is not yet clear whether this is applicable to all or a number of sectors. Antibiotic use is increasing in the Netherlands , Denmark and Germany , while the use is stable in the other five countries examined during this study.

The selection pressure resulted in high prevalence of resistance. Animal associated MRSA is very common in Dutch food producing animals. Moreover, the microbial flora of the gastro- intestinal tract of Dutch food animals is highly resistant and multi-drug resistant. This creates an environment where resistant organisms of concern for animal-, and public health may prosper.