Composting Animal Mortalities

Animals that die in livestock operations are a major management issue. Until recently, a responsible approach for larger animals has been to arrange for them to be taken to a rendering plant. Changes in animal feed regulations and the increasing cost of transport have made this solution less than optimal.

Composting dead poultry has been common practice for some time. The technique is now frequently used by hog producers. Much larger animals, such as cows, can also be safely handled in this way. Most disease-causing organisms are reliably destroyed by the composting process, with one major exception: neither the enzyme action nor the heat in the compost process is adequate to destroy the prions that are associated with BSE (mad cow disease).

Animal mortalities are usually composted outdoors in large bins made of wood or bales. The dead animals are layered with lightly moistened straw or sawdust. For the initial phase, the pile is left undisturbed for 10-14 days. When the internal temperature drops, the pile can be turned. The composting process degrades all but the most resistant parts, such as teeth.

Saskatchewan Agriculture has published an excellent booklet called: Composting Animal Mortalities: A Producer’s Guide.