Usage of veterinary therapeutic antimicrobials in Denmark, Norway and Sweden following termination of antimicrobial growth promoter use.

Antimicrobial growth promoters (AGPs) were phased out in Denmark, Norway and Sweden in 1998-1999, 1995 and 1986, respectively. The annual usage of therapeutic antimicrobials in animals in Denmark almost doubled during the period when AGPs were phased out (1988-1999) and in the subsequent 2 years. The increase was mainly due to an increased consumption of therapeutic antimicrobials in weaning pigs. The annual increase in usage of therapeutic antimicrobials and the annual increase in numbers of slaughter-swine produced in Denmark correlates well, except for 1999 when AGP use was discontinued in weaning pigs, and the following year. In Norway, the usage of therapeutic antimicrobials in animals decreased by 39% from 1995 to 2000. During 2001-2003 the annual usage remained at the 2000-level. The annual numbers of slaughter-swine produced in Norway increased gradually by 10% after the AGP discontinuation (from 1995 to 2003). In Sweden, the usage of therapeutic antimicrobials in animals increased by 21% the first 2 years subsequent to the AGP ban (1986-1988), remained then constant until 1994; from 1994 to 2003 this usage declined by 47%. The initial increase was caused by increased use in broilers and in weaning piglets. The amounts used in animals in Sweden in 2003 were half of the amounts used in 1994. The annual numbers of slaughter-swine produced in Sweden declined gradually by 16% in the study period, although fluctuating. In Denmark, Norway and Sweden the number of dairy cattle and beef cattle declined only slightly in the various study periods while numbers of broilers produced increased notably, especially in Norway and Sweden. Following the termination of AGPs the total usage of antimicrobials (AGPs and therapeutic antimicrobials) in animals in Denmark declined 36% (from 1996 to 2003): in Norway this figure was 45% (from 1995 to 2003). In Sweden, the total usage of antimicrobials in animals in 2003 amounted to only one third of the amounts used in 1984 (decreased from 51 to 16 tonnes). Termination of AGPs was only a temporary risk factor for increased usage of therapeutic antimicrobials in food-animals in Sweden and Denmark; however, an exception might be usage in weaning piglets in Denmark. Furthermore, the discontinuation of AGP use has decreased the overall annual usage of antimicrobials in animals in Denmark, Norway and Sweden considerably.