SURVIVAL OF SALMONELLAS AND ASCARIS-SUUM EGGS IN A THERMOPHILIC BIOGAS PLANT

In a continuous biogas plant, receiving manure from 200 dairy cows and 400 calves and young stock, survival of salmonellas and Ascaris suum eggs was studied. The bacteria and parasite eggs were kept in filter s acs in the manure that had a temperature of 55 degrees C. No viable sa lmonellas or Ascaris suum eggs could be found after 24h in the digeste r. Survival of salmonellas and Ascaris suum eggs was also studied in t he manure pit where the manure was stored after digestion. The tempera ture in the manure pit varied between 22-27 degrees C. Salmonellas sur vived 35 but not 42 days. On day 56, when the experiments had to be st opped, 60% of the Ascaris eggs were viable.