The pin worm is a very widespread parasite which affects especially equids of any age which raised in the stable. They are very fine worms of greyish colour with a lengthening form and being able to measure up to 15 cm. This parasite is not dangerous for the donkey, but causes to him severe itching.

Contamination and cycle of life

The donkey swallows the pin worm eggs present in the litter and food. Then the parasite develops in the intestine until it is an adult (4-5 month), then the females go down along the digestive tract and lay their eggs on the anus' margins.
These eggs are coated with a yellowish adhesive substance and they remain stuck in the perish-anal region. When the donkey is rubbing the eggs fall in the litter, and then they can be infest other donkeys.

The eggs do not survive a long time outside, which explains why we can find this parasite mainly in the animals raised in stables.

Development cycle of Oxyuris equi

Symptoms

In the digestive tract, the pin worm causes small lesions of the intestine, but the main damage is confined to anal irritation. Tail rubbing is therefore a diagnostic feature.

Prévention - Traitement

The majority of the active pest-destroying substances against the ascarids and the strongyles are also effective on pin worms.
Control includes periodic steam cleaning of stables to avoid the survival of eggs and possible infestation of other equids.