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Disposing of Dead Goats
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by Mark J. Estienne,
Ph.D.
Tidewater Research & Education Center
Virginia Tech
**Contact the author for permission to reprint this
article** |
In a typical meat
goat operation, 10% of the kids born live die before
weaning. A death loss of 5% in the breeding herd is
considered normal. |
For a 25-nanny goat farm, producing
1.8 kids per female per year, these percentages translate
into the following annual mortality estimates: five
pre-weaning goats and one nanny goat. Using average
weights of 30 pounds for a pre-weaning goat and 125
pounds for a nanny goat, the amount of mortality produced
by the typical 25-nanny goat operation is approximately
275 pounds per year. Still-born kids, mummified fetuses
and afterbirth add to this estimates. |

Bin for composting animal mortality |
In order to protect
the health of herds and farm personnel, avoid air,
soil and water contamination, and avoid problems with
both agricultural and non-agricultural neighbors,
biologically and environmentally safe methods of dead
animal disposal must be employed on meat goat operations.
A sound herd health program dictates
that goats dying from unknown causes be transported
to a Department of Agriculture Diagnostic Laboratory
for autopsy. This in turn places the burden of carcass
disposal on the state. Producers are charged a fee,
however, for an autopsy and subsequent carcass disposal
by incineration. It is obvious that some dead goats
must be disposed of by the farmer. Current options
for disposal of carcasses include burial, incineration,
and composting. |
Disposal by burial |
Burial is the most common and perhaps
least expensive method of dead animal disposal. A
pit is dug, into which carcasses are placed. Deep
burial (i.e. 4-8 feet) is generally recommended. The
practice of covering dead animals with lime retards
decomposition and is not recommended. Dead goats should
never be buried in areas where leaching can occur.
Problems with burial as a method
of dead animal disposal include odor from and the
accessibility of scavengers to "dead pits"
that are not properly covered. There is also the possibility
of significant ground and surface water contamination,
for which producers may be held liable. Finally, goats
do not die only when the ground is soft. Burying dead
goats in frozen earth may be difficult. |
Disposal by incineration |
Incinerators completely
eliminate carcasses and destroy pathogens. The capacity
of many incinerators is limited, so this method of
disposal works best for goats weighing less than 50
pounds.
In general, incinerators are expensive
to buy and to operate. For example, purchase price
of an incinerator with 600-pound capacity has been
estimated at $2,500 and annual operating costs (i.e.
fuel, maintenance, etc.) May approach $1,000. Certain
types of incinerators may generate air pollution and
objectionable odors. |
Disposal by composting |
The action of thermophilic,
aerobic bacteria converts nitrogen rich (e.g. dead
animals) and carboniferous (e.g. straw, sawdust, etc.)
Materials into humic acids, bacterial biomass and
organic residue (compost). During the composting process,
heat, carbon dioxide and water are generated as by-products.
The resulting product is free from harmful pathogens,
is nutrient-rich and can be used as fertilizer. The
poultry and swine industries have adopted composting
as the method of choice for ridding farms of dead
animals.
In a typical system, carcasses are
placed in a bin containing sawdust, creating an ideal
environment for the growth of the aforementioned bacteria.
The optimal carbon to nitrogen ratio for bacteria
is approximately 30:1.Bacterial action rapidly heat
compost piles to temperatures as high as 160F and
within several weeks carcasses are reduced, leaving
only brittle bones which are easily crumbled. "Turning"
the compost pile by moving it to a new bin (i.e. secondary
bin) after two weeks helps maintain high temperatures
and promote even further decomposition. |
Composting system for a 25-nanny
goat operation |
A bin was situated
over a concrete floor and was constructed of pressure-treated
lumber. The three sided bin was 3 feet tall, 5 feet
wide and 5 feet deep. Four, 4 x 4 posts and several
1 x 6 boards were used. (When sizing composters, it
is typical to provide 100 ft3 of sawdust per 100 pounds
of carcasses to be composted). The unit was covered
with an inexpensive tarp. Total cost (excluding labor)
for construction of this composter was less than $200.
Sawdust is layered on the floor to
a depth of 12-15 inches. A goat is placed on its back
in the layer of sawdust. The thoracic and abdominal
cavities are opened with a knife and deep incisions
are made in the muscles. Intestines are cut and organs
dissected. The animal is then covered with a 12-15
inch layer of sawdust. A second goat can be placed
and dissected as previously described. A final layer
of sawdust is added and a minimum covering depth of
12-15 inches is ensured. Baby goats and afterbirth
can be added to the composter by forming a V-shaped
trough in the sawdust. The mortality or afterbirth
is then covered with 12-15 inches of sawdust.
Sawdust is dampened with water as
needed. The ideal moisture content in a composting
pile employing sawdust is 50-60 percent. The moisture
content of sawdust or a composting mixture can be
judged somewhat by its appearance and feel. Sawdust
that has a damp appearance and feel is probably near
the proper moisture content for composting. Very dry
sawdust may require the addition of 1 to 1.5 gallons
of water per cubic foot of sawdust to obtain proper
moisture content.
Under this system, mature goats have
been completely decomposed in several weeks. Baby
goats and afterbirth are almost completely decomposed
within 24 hours after placement.
Active (as opposed to newly started)
compost piles continue to function through the winter
regardless of ambient temperature. Cold or frozen
carcasses placed in newly started compost piles during
cold weather may not begin composting immediately,
but will start as the ambient temperature rises.
All composting units should be situated
on well-drained soil and provide all-weather capability
access roads and work areas. If properly managed,
composting units are aesthetically "invisible"
and there is little or no risk of air, soil or water
contamination. |
References:
Composting Dead Birds" by D.W. Murphy and L.E.
Carr, Univ. of Maryland Cooperative Extension Service
Fact Sheet No. 537.
"Disposing of dead swine" by D.W. Murphy,
M.J. Estienne, C.N. Dobbins, Jr. and K.A. Foster,
Pork Industry Handbook Fact Sheet No. 133. Purdue
University Cooperative Extension.
Source: Presentation given at "Practical Goat
Farming" Seminar, February 1998, Salisbury, Maryland.
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