Following an initial project begun in 1999 at the Iowa State University (ISU) swine breeding farm, the university’s swine teaching farm started composting mortalities eight years ago in an effort to increase biosecurity practices.

Swine farms manager Jay Lampe said the move was positive.

 “This process has changed our management style and lowered our biosecurity risks at the farm while providing a sustainable way of managing mortalities,” he said.

“Composting has eliminated two potential sources of disease outbreaks for our farms: rendering and fuel trucks entering our property.”

“We are able to decrease the number of outside vehicles like rendering trucks entering the farm grounds, and that helps us keep our biosecurity at a high level,” Lampe said.

The size of and cost to construct a composting facility varies according to available land, type of materials and size of mortalities to be composted.

The swine teaching farm facility is completely roofed with eight bays, each of which is approximately 10 feet square with four foot high concrete walls. This allows adequate space for all carcass sizes from the farm to be incorporated.

ISU agricultural and biosystems engineering professor Tom Glanville said the correct process of preparing and using a mortality composting facility is vital to its success.

“Start by placing a 12-inch layer of dry cover material, like sawdust, wood shavings or chopped corn stalks in the bottom of a compost bin,” he said.

“Decaying carcasses will release excess moisture, so this absorptive base layer plays an important role in preventing release of excess liquid.”

Alternate layers of cover material with additional carcasses until the bin or bay is filled, Glanville said.

“The top layer should always be cover material,” he said. “Realize that you might not be able to fill an entire bin in a short period of time depending on your operation’s mortality rates and size of the moralities.”