Use of biocides on pig and poultry farms and relation with the problem of antimicrobial resistance

Main research question/goal

In this project we develop knowledge about the origin of antimicrobial resistance in the poultry and pig husbandry, with the final goal of getting detailed insight into the interaction with the biocides used (chemical substances which kill or inactivate harmful organisms). The research questions are: Which biocides are used in the poultry and pig husbandry in Belgium and what is the application mode and concentration of these products? What is the effect of use of biocides in the studied sectors on selection for biocide and antibiotic resistance? To what extent does biocide treatment influence transfer of resistance genes? At this moment there is a lack of clarity about the possible relation between the use of biocides in the primary animal production and the development of antimicrobial resistance.

Research approach

Via a cross-sectional study we make an inventory of the use of biocides in the poultry and pig husbandry in Belgium. On the selected farms we perform a survey, we take samples from farm environment and collect bacterial isolates. We analyse these isolates for presence of transferable resistance. By means of longitudinal study on some experimental farms we analyse the effect of repetitive biocide treatment on antimicrobial resistance in the field. We perform in vitro studies to complement or clarify the obtained field results. All data collected will be analyzed to identify the most important risk factors for antimicrobial resistance as a consequence of use of biocides.

Relevance/Valorisation

A cross-sectional field study in broiler and pig nursery units showed big differences in the applied cleaning and disinfection protocols between the farms. The collected E. coli isolates showed high resistance prevalences for different antibiotics, but there were no indications of an increased antibiotic resistance by the use of biocides. Biocide resistance was not found. In vitro exposure of E. coli to subinhibitory concentrations of a frequently used biocide did not affect the transfer of antibiotic resistance genes. No differences were found in antibiotic and biocide susceptibility after repeated use of biocides (longitudinal study). The results of this projects were spread via posters and oral presentations on national and international symposia and were published in scientific journals. They are also included in the PhD research of Helder Maertens.

External partner(s)
Hooibeekhoeve - proefbedrijf voor veehouderij
Ugent - Fac. Diergeneeskunde