Fig. 4.

Distribution of antimicrobial resistance genes (ARGs) abundance and composition. a Stacked bar plot of total ARGs abundance per antimicrobial class (colors), per sample (x axis). b Stacked bar plot of 20 most abundant ARGs (colors), per sample (x axis); the less abundant ARGs were grouped into “Others”. n = 105 metagenomes from 38 independent farms. Nineteen metagenomes per sample type per production system were used, with the exception of extensive-slurry (n = 9). ARGs abundance was expressed as counts per million. MLSP refers to the macrolides-lincosamides-streptogramins-pleuromutilins AMR class