The effect of slurry storage and anaerobic digestion on survival of pathogenic bacteria

摘要

The decline in viable numbers ofSalmonella typhimurium, Yersinia enterocoliticaandListeria monocytogenesin beef cattle slurry is temperature‐dependent; they decline more rapidly at 17°C than at 4°C. Mesophilic anaerobic digestion caused an initial rapid decline in the viable numbers ofEscherichia coli, Salm. typhimurium, Y. enterocoliticaandL. monocytogenes.This was followed by a period in which the viable numbers were not reduced by 90. The T90values ofE. coli, Salm. typhimuriumandY. enterocoliticaranged from 0.7 to 0.9 d during batch digestion and 1.1 to 2.5 d during semi‐continuous digestion.Listeria monocytogeneshad a significantly higher mean T90value during semi‐continuous digestion (35.7 d) than batch digestion (12.3 d). Anaerobic digestion had little effect in reducing the viable numbers ofCampylobacter