The tiny pinworm, Passalurus ambiguous, is the most common worm to infest UK rabbits. Measuring only 5-10mm, adult worms are found in the caecum and the large intestine of affected rabbits. Signs may be absent but affected rabbits may show:
- Poor coat condition
- Weight loss
- Skin irritation around the back end
Young rabbits, especially around weaning, can be heavily infected and may have more serious signs including diarrhoea, lethargy and substantial weight loss.
Rabbits are infected by grazing on contaminated food, meaning worms are much more of a problem in places with many rabbits such as breeders, although wild rabbits can be a source of infection for pet rabbits.