Page 13 - Poultry Mortality Composting

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Figure 3. Composting windrows built in layers

Two Stage Process

After the initial piling of a windrow or completely filling a bin, the material will heat up quickly and then gradually start to cool. The cooling is a normal sign that organisms are starting to be deficient in one of the ingredients. This primary stage for poultry mortalities lasts approximately 4 to 6 weeks. Mix the pile to re-introduce oxygen and redistribute the composting material to encourage rapid decomposition causing the temperatures to rise again. This secondary stage lasts approximately another 4 to 6 weeks. A second mixing process can help to speed the curing stage.

By the end of the second heating stage, carcasses as large as 7 – 9 kg (15 – 20 lbs) are normally reduced to a few brittle bone fragments that are clean and free of tissues that cause odours and attract insects and scavengers. Large birds may need a third heating stage.

Failure to manage the system will result in odours that attracts flies, scavengers and other vermin to the site.

Composting is considered complete when there is: • No soft animal tissue.

• No bones or bone fragments larger than 15 cm (6 in) in any dimension. • No other animal matter larger than 2.5 cm (1 in) in any dimension. • No offensive odours.