Page 7 - Poultry Mortality Composting

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• Inexpensive alternative for poultry disposal.

• Can kill pathogens and reduce chance to spread disease. • Destroys the viability of weed seeds.

• Environmentally safe and valuable soil carbon material. • Can be operated year round. • Utilizes equipment available on-farm. • Low odour generated.

• Low labour and management requirements. • Publically acceptable.

• “Green” option – recycles and promotes biosecurity. • Expands social acceptance.

Composting is the biological breakdown of organic materials in an aerobic (presence of oxygen) environment. Livestock mortality composting requires a high-carbon material with moderate moisture levels and good porosity to surround the carcasses which have a high moisture content and nearly zero porosity. The carcasses and carbon materials are layered into the pile and no mixing is done until after the high-rate (primary) stage of composting has occurred. In and around the animal, the process is anaerobic but as gasses are produced and move away, they enter an aerobic zone. Here the gasses are trapped in the surrounding material which supports bacteria to form a biological filter, or a biofilter. Composting livestock mortalities is best described as an “above ground burial in a biofilter with pathogen kill by high temperature.”

The carbon material around the carcass serves several key functions:

• Surrounds the carcasses making them less accessible and attractive to pests. • Absorbs excess liquids released by decomposing carcasses.

• Provides structure and porosity which promotes air movement throughout the material.

• Provides an energy source for microbial growth.

Avoid turning the pile during the primary stage. After this time, the pile is moved to begin the secondary stage. Moving the pile introduces air and mixes the contents leading to uniformity in the finished compost. The secondary pile is then turned and placed in a pile for storage. Bones sometimes remain intact after completion of the storage process. They are generally quite brittle and pose no health risks or danger to equipment when land applied.

livestock mortality composting