Abstract
Bacterial antimicrobial resistance (AMR) in pigs is an important public health concern due to its possible transfer to humans. We aimed at quantifying the relationship between the lifetime exposure of antimicrobials and seven antimicrobial resistance genes in Danish slaughter pig farms. AMR gene levels were quantified by qPCR of total-community DNA in faecal samples obtained from 681 batches of slaughter pigs. The lifetime exposure to antimicrobials was estimated at batch level for the piglet, weaner, and finisher periods individually for the sampled batches. We showed that the effect of antimicrobial exposure on the levels of AMR genes was complex and unique for each individual gene. Several antimicrobial classes had both negative and positive correlations with the AMR genes. From 10–42% of the variation in AMR gene levels could be explained in the final regression models, indicating that antimicrobial exposure is not the only important determinant of the AMR gene levels.
Highlights
Antimicrobial consumption in pigs is a major contributor to the global antimicrobial consumption in livestock[1]
Faecal samples were obtained from 681 batches of slaughter pig from Danish pig farms
The quantitative association of antimicrobial exposure and antimicrobial resistance (AMR) genes depended on the specific gene as well as the antimicrobial class
Summary
Antimicrobial consumption in pigs is a major contributor to the global antimicrobial consumption in livestock[1]. Data on the purchase of antimicrobials and information on contacts between farms in Danish pig production are available, making the pig farm an ideal study unit for quantifying the relationship between antimicrobial exposure and AMR. Previous studies estimating the relationship between AMR and antimicrobial exposure in pig populations have primarily focused on phenotypic resistance in one or few bacterial species[9,10,11,12,13,14,15] This method underestimates the risk of AMR genes present in porcine faeces, as large parts of the gut microbiota cannot be cultured by traditional means[16]. The factors driving AMR in pig production requires investigation in order to introduce efficient initiatives to reduce the levels These factors are best studied in environments reflecting real-life practices. The objective of this study was to quantify the association between the lifetime exposure of pigs to antimicrobials and the levels of seven AMR genes, ermB, ermF, sulI, sulII, tet(M), tet(O), and tet(W) in Danish slaughter pig farms
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call