Composting large ruminant animals
A challenge for farmers is the proper disposal of large, dead ruminant animals.
The state of Missouri requires that all dead animal carcasses be properly disposed of within 24 hours. Five acceptable options are rendering, composting disposal in approved landfills, incineration and burial.
University of Missouri researchers looked at four dead-animal composting systems for their feasibility, flexibility and financial viability. They studied two mechanical composting systems--the Dutch Composter and the BIOvator--and evaluated two static pile compost systems--unroofed and under roof.
Of the four systems, researchers recommended a compost system for regional animal mortality using static piles under roof.
"A well-designed composting facility using sawdust, woodchips and other carbon sources could significantly increase efficiency and enable throughput for animal mortalities," said Joe Parcell, MU agricultural economics professor.
The mechanical composting systems are too costly for individual farms, he said. At much lower costs, the static pile under roof offers minimal environmental risk and handling of dead animals. Such a system offers the most flexibility of scale, can operate in all weather conditions and be most easily implemented with minimal management, the study found.
Missouri has 584 million pounds of yearly mortalities from the beef, hog, horse and deer populations. Researchers targeted southwest Missouri, with its high density of cattle, proximity to environmentally sensitive areas and need for increased economic activity. Mortality-compost feasibility studies could be implemented in other areas of Missouri, Parcell said.
Such a facility could serve farmers, small-scale meat processors and livestock auctions.
Nutrient composition should be sufficient for nearby farms to use the compost as a soil amendment if they can pick it up from the composting site. All four systems were assumed to be built into a facility capable of handling 1,500 mortality pounds per day. Fees assessed for each 1,500 pounds to be composted were estimated at $75.