A soil compost workshop at Terang’s DemoDAIRY last month was told that using dead stock as part of a compost system would solve problems faced by more and more dairy farms; how to dispose of deceased animals.
The workshop, attended by 66 farmers and service providers, was hosted by the Future Ready Dairy Systems and Glenelg Hopkins CMA as part of the reducing soil acidification project.
Guest speaker Kevin Wilkinson from the Department of Primary Industries’ Future Farm Systems Research Division said a reduction in knackery and rendering services and stringent EPA guidelines reduced options for dairy farmers.
“You just can’t dump dead stock in a back corner of the farm; it is an environmental risk and illegal,” Dr Wilkinson said.
“Deceased stock can be composted very successfully and simply,” he said.
Dr Wilkinson said ‘mortality composting’ was a natural biological process and could apply to any farm animal.
The resulting compost can provide organic matter and nutrients to improve soils.
The system involves placing 50-60cm of absorbent carbon material (such as sawdust) under the animal and then covering it with 60-90cm of the same type of material.
“The animal is encased above ground with clean organic material which acts as a barrier to prevent odours escaping and keep scavengers away,” Dr Wilkinson said.
A cow compost pile should be turned after about four months to expedite decomposition and water can be added as needed to promote the breakdown of the body.
The entire process takes six to eight months, including a curing phase to complete the composting.
Dr Wilkinson said the breakdown was thorough.
“You will be left with some larger bones that won’t decompose but that is a lot easier than having to dispose of the whole animal,” he said.
Dead animals can also be added to existing compost heaps but with the same requirements of being encased in carbon material.
Dr Wilkinson said farmers should follow health and safety precautions such as wearing gloves and protective masks when handling dead stock or compost materials.
The session was funded by Dairy Australia, Australian Government Climate Change Research Program and the Australian Government’s Caring for our Country.
