Lungworm
Lungworms are white in colour and can be anything from 6 /10 cm in length. Donkeys are the natural host for these worms and don't usually show any symptoms.
Lungworm is difficult to diagnose and can cause respiratory problems. They are found in the lungs and mostly in donkeys. If horses are grazing in the same field or the field was used before the horse arrived, then they can be effected.
The worms rarely completes its life cycle in horses and most of the time they are not picked up by a faecal worm count.
If the horse has a high number of the Lungworm larvae, then the horse will start with a persistent coughing.
The only way to treat lungworm is with anthelmintics (wormers) containing any of the chemicals ivermectin, moxidectin or benzimidazole. These chemicals will remove both the migrating larvae and adult worms.