If a lungworm infection is suspected then a faecal sedimentation test is used to confirm this in the laboratory. This separates out the comparatively heavy eggs of the lungworm from the faecal matter for identification under the microscope. Because the parasite rarely reaches egg laying potential in the horse, it is often better to test the donkeys or mules thought to be the host of infection, rather than the horse that is showing symptoms.
Testing is carried out all year round and treatment is recommended if any evidence of lungworm infection is seen in the sample. A sedimentation test requires 2-3 times the amount of faecal matter than a worm egg count and takes a number of days to complete.
Treatment for lungworm
Ivermectin and moxidectin are the most effective treatments for lungworm. Both can be used in horses but not all ivermectin based wormers or moxidectin are licenced for use in donkeys. If in doubt, check with your vet or SQP. The Donkey Sanctuary recommends using the Eqvalan brand over generic ivermectin wormers because of treatment results they have seen in their animals.
General guidance on worming donkeys
In line with all equines the British Equine Veterinary Association advocate a targeted worm control programme for donkeys based on worm counts and tests. Treatment should be given only if the tests indicate and for specific seasonal problems like encysted redworm, lungworm, bots and pinworm. This is to help slow down resistance to the drugs as well as being better for the donkey and the environment.
Worm counts should be carried out every three months to test for redworm and roundworm and an EquiSal saliva test taken every six months to test for tapeworm. While the EquiSal test has not been scientifically validated on donkeys at post mortem level, we still test many donkeys with good effect. Foals, youngstock and those who have had a poor start will require more attention.
A winter dose for the possibility of encysted redworm should be given between December and February with a 5 day dose of fenbendazole with a resistance test to test efficacy (moxidectin is not licenced for use in donkeys).
If tapeworm treatment is required then double dose with pyrantel is advised as praziquantel is not licenced for use in donkeys.
Mules should be treated in line with advice on donkeys as it is generally accepted their systems bear more similarities to this side of their parentage.