Carcase composting works

Carcase composting project site
Research at Elizabeth Macarthur Agricultural Institute (EMAI), Camden, is showing composting is an effective way of managing livestock mortalities.

A trial near completion at Elizabeth Macarthur Agricultural Institute (EMAI), Camden, is showing the viability of composting large numbers of livestock carcases.

Composting could be a solution to managing animal mortalities caused by exotic disease outbreaks such as foot and mouth disease, capable too of reducing associated biosecurity risks.

More broadly, it could also work for drought, floods, fire and natural causes.

The project, now close to conclusion, is evaluating the potential risks of composting and developing standard operating procedures.

The effectiveness of different options - surface disposal, static pile composting and above ground burial - is under scrutiny.

The project started in March with the construction of the windrows and burial of 35 cattle carcases.

Monitoring has revealed temperatures of the carcases subjected to composting were consistently between 50-60C, suggesting conditions are adequate to pasteurise the carcases and adjacent material.

In contrast, temperatures surrounding the carcases buried above ground were only 20-25C.

Fecal coliforms and E.coli have been used as indicators for evaluating the survival of disease causing organisms in each of the management options.

After four weeks, none of the indicators survived in static pile composting treatments, although viable cultures were obtained from the surface disposal and above ground burial treatments.

"These results are very encouraging and demonstrate composting is a viable option for managing animal mortalities,” DPI recycled organics technical specialist, Chris Dorahy said.

Monitoring and evaluation will finish in September with the fifth and final sampling period.