Beef molecular biologist Tim Reuter was intrigued and disappointed when a galvanized chain nearly dissolved in a manure compost experiment.
He was intrigued by compost properties that could break down metal but disappointed that weakness in the chain made it necessary for him and his crew to dig into a compost pile that contained manure and dead animal parts.
Reuter and beef research scientist Kim Stanford are studying the ability of the compost process to degrade animal carcasses and specified risk material and reduce or eliminate livestock pathogens such as anthrax, E. coli O157:H7, campylobacter, Newcastle disease and prions.
Some research was done in biosecure lab facilities because of the nature of the pathogens, but the Alberta Agriculture researchers also conducted a large scale study in a compost structure with numerous animal carcasses covered in manure and a manure and sawdust mixture.
They found that the composting process degraded virtually all parts of the carcasses, partly because of temperatures greater than 55 C reached during the composting process.
Hoofs were used as models for prions in some of their studies, due to their molecular structure, Reuter told a Jan. 14 manure management update meeting in Lethbridge.
“After 230 days, we had more or less 95 to 99 percent reduction or degradation of these hoofs.”
Most pathogens were reduced by at least 99 percent, with the exception of the bacteria related to Johne’s disease.
Anthrax was reduced but not eliminated and the same was true for infectious prions.
In their abstract, Reuter and Stanford concluded that “composting is (an) effective alternative to eliminate infectious pathogens from re-entering the food and feed chain and subsequent disease related losses or costs.”
They also found that while composting reduces manure volume, it also makes nutrients more available for plant nutrition and can reduce fertilizer costs.