This decrease is mainly due to the sales of antimicrobials belonging to Tetracyclines (decrease of 22.2 % i.e. 139 tons) and to Sulfonamides (decrease of 32.0 % i.e. 86 tons). Compared to 1999, the sales of Fluoroquinolones have increased of 48.94 % (i.e. 1.61 tons) and the sales of Quinolones have decreased of 63.3 % (i.e. 12.99 tons). Compared to 2008, the sales of Fluoroquinolones have stabilized in 2009 (+0.09 %) Compared to 1999, the sales of 3rd and 4th generation Cephalosporins have increased of 105.6 % (i.e. 0.94 ton) and the sales of 1st and 2nd generation Cephalosporins have increased of 28.4 % (i.e. 1,5 tons). Compared to 2008, the sales of 3rd and 4th generation Cephalosporins have decreased of 13.7 % (i.e. 0.29 ton).
Sales in weight of active ingredients per Kg of animal bodyweight When taking into account the weight of animals treated, the decrease is only of 11.83 % compared to 1999. In 2009, sales correspond to an equivalent of 67.73 mg/Kg of animal weight produced. The sold tonnages per class do not represent accurately the use of antimicrobials as differences in dosages and durations of administration are not taken into account. Antimicrobials belonging to the new classes generally require a lower weight of active ingredient to treat one animal than an old antimicrobial.