Veterinary antibiotics (VAs) and anthelmintics (AHs) are used to control microbial and parasitic infestations in livestock farming respectively. These compounds are not metabolized in the animals' body and animal excretes containing VAs and AHs are used as soil manures facilitating the dispersion of VA and AHs residues to agricultural soils. This imposes significant pressure in the soil microbial community for selection and further dispersal of resistant traits for VAs and constitutes a threat for water quality since VAs could move from soil to aquifers and some AHs like benzimidazoles are particularly persistent in the environment. To date little is known about the biodegradation of these veterinary drugs. It was recently shown that the continuous soil exposure to sulfonamides and macrolides could select for resistance and for VA-degrading traits. Today only a few VA-degrading bacteria are available and nothing is known about the biodegradation of AHs. Bacteria carrying biodegradation traits against these veterinary drugs could be exploited for the bioaugmentation of contaminated manures and soils. We aim to explore the complex interactions of veterinary drugs with soil microorganisms, look into evolutionary mechanisms that drive the selection (antibiotic resistance vs biodegradation traits) and exploit biodegradation to avert environmental threats by VAs and AHs.
- Stathis Lagos, PhD student