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A sufficiently high composting temperature should inactivate many common pathogens likely to be present in solid animal waste. Monitoring core temperatures inside compost heaps is not straightforward, which means that heaps are not generally monitored. An alternative is to monitor surface temperatures and use those data to infer core temperatures, and thus whether pathogen inactivation has occurred. This paper describes two methods (thermal imaging and thermocouples) for the measurement of surface temperature, and a modelling approach using time series analysis to predict the temperatures obtained in the core of aerated heaps of composting pig farmyard manure (FYM) from surface temperature data. The model was able to predict core temperatures in the heap quite closely for a period of time for well insulated parts of the heap, although predictions were further from observed values close to the surface of the heap and the aeration pipe.

This review discusses a number of possible treatments for pathogen disinfection and evaluates them for their applicability in inactivating viruses in either dilute or concentrated pig slurry, particularly on a large scale. Methods are discussed under the headings of chemical, physical and other treatments. From those methods considered, it appears that the most suitable treatments are the use of heat at about 60°C for up to 30 min, or the application of an appropriate concentration of chemical, such as sodium or calcium hydroxides, or formalin. Aerobic and anaerobic treatments are also known to have virucidal effects, and could be used to assist decontamination on farms where such technologies are already used in routine slurry treatment.

Livestock manure may contain pathogenic organisms which pose a risk to the health of animals or humans if the manure is not adequately treated or disposed of. One possible treatment method is composting. However to ensure that pathogen destruction occurs, temperatures need to be sufficiently high throughout the heap to ensure that pathogens are inactivated. The temperature required to inactivate a marker organism, Escherichia coli 11943, has been investigated, and found to depend on substrate composition, moisture content and duration of incubation. Results show that temperatures in excess of 55 degrees C for 2 h are required for inactivation. Data are presented showing the levels of faecal coliforms in compost heaps where temperatures did not rise above mesophilic levels (35 degrees C where samples were taken).