OLDS, Alta. – A new process to safely dispose of condemned carcasses and animal parts is being studied in Alberta.
With the diagnosis of chronic wasting disease in an Alberta elk, renderers have found they can no longer sell some of their material overseas, said an Alberta Agriculture meat specialist.
About 15,000 wild deer and elk are killed by hunters each year in the province, but renderers do not want their heads, offal or bones.
“They have now said they cannot accept any through their rendering facility,” said Chris Giffen at the Olds College composting conference May 8.
Read Also
Dry summer conditions can lead to poor water quality for livestock
Drought conditions in the Prairies has led to an decrease in water quality, and producers are being advised to closely monitor water quality for their animals.
“There are lot of bones that showed up in ditches and landfills this year,” he added.
Disposing of condemned carcasses and body parts of animals prone to transmissible encephalopathies is becoming a growing problem for meat processors. About 5,000 tonnes of material must be disposed each year. At the moment they are either composted or dumped in landfills.
“Landfill is no longer a good option,” Giffen said.
“We do have high risk materials that we are putting in the landfills.”
An American company, WR2 of Indiana, has developed a process that reduces carcasses to bone powder and appears to destroy prions, the rogue proteins thought responsible for TSEs.
The company’s alkaline hydrolysis tissue digester uses an alkali solution working under pressure to convert cells and tissues into a solution of amino acids and sugars. It reduces the weight of material by 97 percent.
The solids are reduced to “bone shadows” that crumble into powder when touched. Water is drained into a sludge that can be flushed down the sewer and the dry matter can be used as bone meal fertilizer.
Low pressure units can handle about 3,000 pounds of material in 18 hours while high pressure units can break down 7,000 lb. in six hours.
Some veterinary labs and clinics are using the digesters in the United States to dispose of euthanized animals and pets.
They have been widely used in Vermont to dispose of scrapie-infected sheep and other states have used them to get rid of CWD-infected cervids. They are also used in Great Britain, where cattle older than 30 months are still destroyed to prevent BSE from entering the food chain.
The machinery was developed in the medical sector to dispose of bio-medical waste, including hospital linens, needles, tubing and body parts.
