Waste Management
Composting Livestock Mortalities
By J. R. Morris, T. O’Connor, F. Kains and H. Fraser
Oct 28, 2002, 11:00pm

http://www.gov.on.ca/omafra/english/livestock/swine/facts/97-001.htm   Title:

Composting Livestock Mortalities

Division:		Agriculture and Rural
History:
Written by:		J. R. Morris, T. O’Connor, F. Kains and H. Fraser

Table of Contents 

1. Introduction
2. Guidelines
3. General Comments
4. For more information... 

Introduction

 Mortalities are a fact of life for commercial livestock producers. Livestock and poultry die from disease, accidents, or competition. Under the Ontario Dead Animal Disposal Act, farmers with dairy or beef cattle, swine, sheep, horses or goats are obligated to dispose of dead animals within 48 hours, after knowledge of their death, in one of three ways, by:

1. Licensed Dead Animal Collectors
2. Burial under 0.6 m (2 ft.) of soil
3. Composting

This Factsheet deals with composting as an alternative for disposal of mortalities.

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Guidelines

1. Site

The compost facility should be located in an area that is well-drained and has all-weather access to roads and work areas. Avoid areas that could cause leaching of contaminants into the ground water. Consider traffic patterns for the handling of mortalities and sawdust or other carbon sources. Offensive odours and flies are minimal if the compost piles are properly managed. However, suitable distances should be maintained from farm and neighbouring residences and compost facilities should be out of sight as much as possible. The working side of the compost facility should face south where possible. Also, at certain times of the year, flies will be attracted to the area (first frost days in fall). A preferred site would be in a remote location on the farm.

2. Base

There is some run-off from the unit (surface and within), however, the nutrient levels are relatively low. The compost unit should be located on the soil surface with drainage away from the site. No concrete floor is needed.

3. Carbon Medium

Sawdust is the best medium to mix with mortalities. Other high carbon materials including chopped straw, corn cobs, corn silage, mixture of manure and straw/sawdust, etc. may be possible but sawdust in research trials at the Ridgetown College of Agricultural Technology gave highest temperatures and fastest breakdown of materials.

For every kilogram of mortality to be composted one kilogram of sawdust is needed. If the mixture gets too dark during the compost period, more sawdust should be added. The mortalities can be buried into the medium as they occur. (A 20 litre pail of sawdust weighs approximately five kilograms.)

4. Structure

The structure can be relatively simple. In Missouri, plastic-wrapped, large round bales were used to form walls around the compost unit. However, because of the risk of wild life entering the area, some walled structure (at least 1.5 m or 5 ft. high) is recommended. Figure 1 shows the experimental unit used at the Ridgetown College.

Figure 1 – The Experimental Compost Facility Used for the Studies at the Ridgetown College of Agricultural Technology

5. Management

To start, add 600 mm (2 ft.) of sawdust to the floor of the bin. Place the mortalities in the sawdust. Mortalities must be placed in the bins and covered with sawdust as soon as they occur. Mortalities must be placed at least 300 mm (1 ft.) from the edge of the bins and covered with a minimum of 600 mm (2 ft.) of sawdust. A daily check must be made to ensure that the mortalities are adequately covered. Settling of the pile, and wind can move the sawdust.

A compost cycle would be three months to fill, three months sitting, then turning the material from one bin to a second, and allowing it to sit for a further three months (see Figure 2 below).

After turning, if there are any mortalities showing, cover them with at least 300 mm (1 ft.) of sawdust. Figure 3 shows the resultant compost six months after placing the mortalities in the compost facility.

For wintertime use, a compost pile should be initiated in November, filled over the winter, turned in May, and emptied in September. Avoid initiating a compost pile in December to February.

Figure 2 – A Schematic to Illustrate the Management of the Composting Process

Figure 3 – The Resultant Compost Material After a Six Month Composting Period for Swine Carcasses

6. Sizing a disposal unit - A case study on sizing your own composting facility is given below:

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General Comments

• There are sufficient catalytic bacteria, enzymes, etc. within the mortalities to degrade them over time.
  
  
• Make sure that the mortalities are covered by at least 600 mm of sawdust immediately upon placing it in the pile. Warm mortalities degrade much more rapidly than cold ones. Immediate burial in the compost piles eliminates the risk of wild animals or dogs removing them. It also reduces the odour.
  
  
• At the end of the compost cycle, the product is still not completely stable. The mortalities are simply degraded to small segments and bones demineralized so that further degradation can be completed once spread on the land, much similar to the spreading of manure. This material could be placed in a solid manure storage facility until the appropriate time for spreading.

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This Factsheet was authored by: J. R. Morris, Ridgetown College of Agricultural Technology, T. O’Connor, Meat Industry Inspection Branch, OMAFRA, F. Kains and H. Fraser, Agriculture and Rural Division, OMAFRA.

For more information... contact Gary Koebel at: gary.koebel@omaf.gov.on.ca