Isolation of multidrug resistant coliforms and their bacteriophages from swine slurry

Abstract

Slurry management is a contemporary agricultural problem. Although liquid manure is a valuable fertiliser, it may posea microbiological threat due to spreading of bacteria resistant to various antibiotics. Fermentation has been proposed as a solutionto this problem, although it does not fully eliminate the antibiotic-resistant strains. The presence of gram-negative rods resistantto antimicrobials may cause an uncontrolled transmission of resistance factors and genes in the natural environment. Therefore, abiocontrol system is necessary to prevent this phenomenon. The aim of this study was to detect multidrug-resistant (MDR) bacteriaand their lytic bacteriophages in raw swine slurry. For that purpose, MDR bacteria from the family Enterobacteriaceae were isolatedand tested with bacteriophages using a modified detection method. The study suggests that the bacteriophages present in the slurry areactive against MDR bacteria and possibly could be used as a biocontrol agent for reduction of these microorganisms in fertilisers ofanimal origin. In the scope of the results obtained, a novel approach for the evaluation of slurry based on the preselection method isproposed. Moreover, the study reports the first case of isolation of a bacteriophage active against Providencia alcalifaciens.