Investigations on the role of Stomoxys calcitrans as bacterial reservoir and distributor of antimicrobial resistance in swine production

The stable fly, Stomoxys (S.) calcitrans, is distributed worldwide. Using its proboscis the stable fly causes not only pain, but also may transmit infectious agents such as PCV2 and haemotrophic mycoplasmas via the blood feeding act [1]. Schwarz et al. (2020) detected staphylococci and enterobacteria as the most frequent families of bacteria on stable flies (25% and 39.7% respectively). The aim of this project is to further elucidate the role of stable flies as a reservoir and distributor of resistant Gram-positive cocci, such as staphylococci and streptococci, and Escherichia coli compared to house flies. Moreover in this project indicator organisms should be monitored. Therefore, fly specimens will be collected as pools from 40 piglet producing farms (4*10 stable flies, 4*10 house flies; in total 320 pool samples) in relation to the total use of antimicrobials in the corresponding farm. Additionally, boot sock samples (BSS) and dust wipe samples (DWS) will be collected to investigate microbiota of surrounding stable equipement/environment. Results of this study will provide a basis for the estimation of the relevance of stable and house flies as reservoirs and distributors of staphylococci/streptococci and E. coli resistant to antimicrobials (AM). As a consequence, improved protocols for the control of insects in pig producing farms can be developed to support the battle against the emergence and distribution of antimicrobial resistances of bacteria.

Zentrum für Lebensmittelwissenschaften und Öffentliches Veterinärwesen
Klinisches Zentrum für Populationsmedizin bei Fisch, Schwein und Geflügel
Zentrum für Pathobiologie
Zentrum für Lebensmittelwissenschaften und Öffentliches Veterinärwesen
Zentrum für Pathobiologie