Public examination of dissertation 13 October 2017: Antibiotic resistance in agroecosystems
Ms. Johanna Muurinen, MSc (Agriculture and Forestry) who works in Risk Assessment at Finnish Food Safety Authority Evira is about to defend her doctoral dissertation in the Department of Food and Environmental Sciences of the Faculty of Agriculture and Forestry at the University of Helsinki.
Antibiotics are administered to production animals and their manure is used as fertiliser everywhere in the world. Due to antibiotic use in animals, resistant bacteria are selected in the animal gut. Thus the bacteria, their resistance genes and possible antibiotic residues may spread into the environment. Antibiotic resistant bacteria occur naturally in the environment, and if they enrich in soil as a result of fertilisation, they may be transported to livestock animals among the harvested forage . The objective of the work was to investigate if Finnish livestock production disseminates antimicrobial resistance, or if resistant bacteria in the soil are enriched due to manure fertilisation. Despite that the antibiotic resistance genes of bacteria disseminated to the soil as result of manure application, there was a clear reduction in their abundance and richness by the forage harvesting time. In this study, antibiotic residues were not detected in manure, and thus environmental problems caused by antibiotic residues originating from Finnish livestock production are hardly to be expected. Genes conferring resistance to "last resort" antibiotics were identified in Finnish agroecosystems, but these genes were not clearly enriched as a result of fertilisation. This finding demonstrates that also Finnish agroecosystems may contribute to the spreading of resistance, if agricultural practices or antibiotic usage policies would be changed.
Ms. Muurinen conducted her work in the division of Microbiology and Biotechnology in the Faculty of Agriculture and Forestry at the University of Helsinki. The work started in 2013 and was supervised by Professor Marko Virta. Maj and Tor Nessling Foundation and Academy of Finland funded the project.
The public examination of the dissertation will take place on Friday 13 October 2017 at 12.00 p.m. in lecture room 1031 of Bio Centre 2, address Viikinkaari 5.
The examination is conducted in English.
For more information, please contact:
Johanna Muurinen, Researcher, tel. +358 50 465 2249