Publikationsdatenbank

Ex-vivo screening assay of pre- and probiotic combinations for the inhibition of pathogenic Escherichia coli in sows (2020)

Art

Poster

Autoren

Zeilinger, K. (WE 4)

Vahjen, W. (WE 4)

Hellmich, J. (WE 4)

Zentek, J. (WE 4)

Kongress

24th ESVCN Congress

München, 17. – 19.09.2020

Quelle

Congress Proceedings : 24th Congress of the European College of Veterinary and Comparative Nutrition : September 17 - 19, 2020 — Ludwig-Maximilians-Universität München (Hrsg.)

München, 2020 — S. 124

ISBN: 978-90-90-33625-1

Sprache

Englisch

Verweise

URL (Volltext): https://www.zora.uzh.ch/id/eprint/190612/1/Congress_proceedings_2020_ffv_(4).pdf

Kontakt

Institut für Tierernährung

Königin-Luise-Str. 49
14195 Berlin
+49 30 838 52256
tierernaehrung@vetmed.fu-berlin.de

Abstract / Zusammenfassung

Introduction:
Although pro-/prebiotics have been widely used in pig production, thereare still inconsistent results on their efficacy [1, 2]. Beneficial effects depend not only on the probiotic strains or the prebiotic structure, but also on dose, animal type, health status, sanitary conditions, diet and age [3, 4]. Therefore, pro-/prebiotics should be applied in a targeted way, which includes conditions on individual farms. The aim of this study was to develop an ex-vivo screening assay to find tailor-made combinations of pro- and prebiotics for individual farms for the inhibition of enteropathogenic Escherichia coli (EPEC).

Animals, material and methods:
Fecal samples were obtained from 20 German pigfarms. Three samples from each farm were used for ex-vivo analyses. Three probiotics(Bacillus licheniformis and Bacillus subtilis, Saccharomyces cerevisiae boulardii,Enterococcus faecium) and three prebiotics (Inulin, Fructooligosaccharide, Mannan-oligosaccharide) were selected alone or in combination to test their effectiveness toinhibit the growth of an EPEC model strain ("Abbotstown") in fecal samples. Thus, a total of 16 ex-vivo assays was performed for each sample. Fecal sample slurries weremixed with pro-/prebiotics and the EPEC strain and incubated anaerobically for 24h at 37°C. Aliquots of the incubated slurries were transferred to a medium containing a specific antibiotic mixture. During incubation for 24 h at 37°C, growth was recorded (OD690nm) in a microplate reader. Comparison of exponential growth phase OD values from pre-/ probiotic supplementation to controls without supplementation were used to analyze the survival of the EPEC strain. A mixture of three antibiotics(cloxacilline, metronidazole and vancomycin) was used to ensure selective growth ofthe EPEC model strain in the fecal slurries. The specificity was confirmed by the absence of growth in all fecal samples not inoculated with the model strain.

Results and discussion:
Analysis of the growth curves showed that the time point of8 h was most suitable to compare EPEC growth in controls to pre-/probiotic supplemented samples. Suppression of E. coli growth was not always observed, as some pro-/prebiotic combinations also led to increased growth of the model strain in some samples. Our results indicate that the survival of the model strain depended not only on the added pre/probiotics, but also on the origin of the fecal samples used. Thus, in-farm variation of E. coli growth was much lower than differences between farms.

Conclusion:
The ex-vivo assay depends on a suitable antibiotic mixture to allowspecific growth of a pathogen model strain after incubation with pre-/probiotics. The use of fecal samples includes the response of the individual microbiota and is therefore preferred to in -vitro assays. The developed method has the potential to find tailor-made combinations of pro - and prebiotics for individual farms to inhibit pathogenic E. coli, as many combinations can be tested in parallel.