Changes in Surviving E.coli, Coliform Bacteria and General Bacteria in Manure with Air Drying Treatment

Abstract

Approximately 87 million tons of dung is being produced annually from cattle farms all over Japan. Considering the proper treatment of this waste product, applying manure to farmlands has been focused from a viewpoint of popularizing organic agriculture. However, pathogenic bacteria known as E.coli may be released from the immature fermented manure that was applied in farmlands. So, the treatment for decreasing E.coli should be considered. Although air drying is known as an effective treatment for decreasing E.coli, it might affect beneficial bacteria as well as pathogenic bacteria. So, this study dealt with the observation of the change in several microorganisms such as E.coli, coliform bacteria and general bacteria under air drying treatment. In the experiment, 3 types of cow manure such as fresh, 2 weeks fermented and 12 weeks fermented were employed. Air drying treatment was carried out to observe the survival of E.coli, coliform bacteria and general bacteria during 28 days. The experimental results showed that the number of E.coli and coliform bacteria decreased with passing day of air drying process. Also, the number of general bacteria decreased with time of air drying process. However, it was considered that the decrease in general bacteria possibly affects the decomposing process of manure. Therefore, it was concluded that air drying treatment for fresh cow dung is not a proper way but is applicable to the manure fermented for 2 weeks or 12 weeks.