Sanitization efficacy of anaerobic digestion and aeration of slurry from the aspect of limiting emission of Salmonella into the environment.

The aim of this study was to estimate the usefulness of mesophilic anaerobic digestion and aeration for sanitization of slurry from the aspect of limiting transmission of Salmonella into the environment. Material for the study was fresh pig slurry. Collected samples were subjected to anaerobic digestion at 35°C and aeration with an initial temperature of 35°C. The efficacy of both methods was examined based on determination of the elimination rate and theoretical time of survival of Salmonella Senftenberg W(775), Salmonella Enteritidis and Salmonella Typhimurium introduced into slurry in carriers of type Filter-Sandwich. Samples for the study were collected every 24 hours and the number of bacilli was determined with the MPN (Most Probably Number) method. The study indicated that fermentation is a more effective method for slurry sanitization. A higher rate of elimination and shorter time of survival of all the tested bacteria was observed, compared with the use of aeration. The experiment allowed us to prove the high sanitization efficacy of both examined methods. They ensure the full elimination of the tested serotypes of Salmonella in only slightly more than 10 days. The use of fermentation or aeration as a way of slurry treatment for agricultural purposes makes it possible to obtain a fertilizer which is valuable and safe for humans and the environment.