Worming farm dogs
Encouraging dog walkers to regularly worm their dogs is vital - but so to is having a strict routine for farm dogs. Farm dogs can be at higher risk of contracting tape worms due to their increased access (compared to non-farm dogs) to infected sheep meat.
Dogs, and occasionally foxes, that having ingested tape worm parasites will then pass eggs in their faeces (up to 750,000 eggs a day). Sheep, on consumption of contaminated grass or water, ingest the larval stages or oncospheres which penetrate the gut wall and travel via the blood to target organs. Once there, they develop into larval Cysticercus cysts. It is not possible to treat the sheep and so treating dogs is vital.
To prevent farm dogs infecting your sheep it is recommended that they are wormed with a praziquantal wormer every six weeks, following which they should be kept off the land for 48 hours. The recommendation of worming every six weeks comes from the fact that some of the common dog tape worm species have a prepatent period (the time between ingesting the parasites and shedding eggs in their faeces) of six weeks. In addition, dogs should not have access to, or be allowed to consume, sheep carcasses.
Further measures to protect you flock would include restricting access to your pastures of dogs not known to be treated and informing the public about the potential implications of not worming their dogs. You can print off and use the poster below if it will help with this.