JUST one dog or fox dropping can contaminate an area with tapeworm eggs for up 12 months, causing sheep measles (Taenia ovis) that’s costing losses to the meat industry of $2.4 million annually.
The answer, according to one of Australia’s largest sheep and wool growers and abattoir operator, Roger Fletcher, is to keep healthy dogs, and fox populations down.
Sheep measles are formed when sheep eat tapeworm eggs on pasture or in feedlots.
Once ingested, the eggs hatch and larvae migrate through the gut wall, travel through the body and localise in muscle, particularly the heart and diaphragm.
Dogs become infected when they are fed sheep meat or scavenge carcases with viable cysts.
Mr Fletcher, managing director of Fletcher International Exports, Dubbo, said trials with lambs and no dogs on one property over a three to four-month period with lambs being finished and killed during the period showed no signs of sheep measles until the last mob.
“And they were riddled with infection,” he said.
The trial proved foxes also played a significant role in spreading the infection.
“When you intensify sheep numbers, particularly in a feedlot situation, dogs are disasters,” he said.
“Keep dogs away from those areas and make sure you control fox numbers and wild dogs if any.”
Mr Fletcher said sheep measles can be controlled just by keeping working and house dogs healthy.
Livestock Biosecurity Network’s Dr Patrick Kluver said prevention is aimed at breaking the tapeworm life cycle.
“If dogs do become infected, ensuring the tapeworms are killed before they can produce eggs is paramount,” he said.
“There are two other important tapeworms that have a sheep/dog life cycle that cause hydatid cysts and bladder worm in sheep.
“These will also be controlled by following the same prevention program.”
Precautions to protect dogs and sheep from infection recommended include worming all farm and house dogs monthly with a wormer containing the active ingredient praziquantel.
Hunters or contractors should provide evidence their dogs have been treated at least three days to one month before entering a property.
Feed commercial packaged dog food and no access to sheep or goat carcases.
Secure dogs at night to stop scavenging and remove sheep carcases to stop access for domestic dogs, wild dogs and foxes.
Consider burying, burning or creating a fenced – dog-proof – offal pit.
All home killing of sheep should occur in a dog-proof enclosure to stop the ability for eggs to spread some distance because control works best when organised on an area basis.
Worm all dogs on the farm, first step
PREVENTION is the key to the control of sheep measles.
The tapeworm parasite causes small cysts that lodge in muscle tissue, especially the heart and diaphragm of sheep.
Fletcher International Exports managing director Roger Fletcher said while infections cause $2.4 million damage to sheep meat annually, the cysts are unacceptable to consumers.
“Our customers today are most discerning and demand, and are receiving, quality meat from their butcher,” he said.
“But while we work diligently within our abattoirs to detect infections, sheep and prime lamb producers need to do their part in breaking the parasite’s life cycle on the farm.
“Make sure all dogs are wormed on a monthly basis is the first step.”