Canine whipworms are blood-sucking internal parasites, about 2 inches long. They are thin at their head ends, with fat tail ends, making the worms whip-shaped. They live in a dog's small and large intestine, but the worms' eggs need to develop outside in the soil before they can be transmitted to a new host.
Whipworms start life as eggs laid in a dog's large intestine and pass out with his stools. The microscopic eggs take two to four weeks to develop in the soil -- not the fresh stools -- before they reach the infective stage where the eggs contain larvae. The eggs can survive for up to five years in the environment. The new host will consume the eggs, usually by grooming, and they will hatch, releasing the larvae in the dog's small intestine. After about a week, the young worms move into their permanent home in the large intestine where they embed their heads into tissue. About 74 to 87 days after the dog ingested the eggs, the whipworms are ready to mate and start the cycle again.
A dog with a heavy infestation of whipworms can develop chronic, bloody diarrhea. Treatment is with an appropriate worming product -- see a veterinarian for advice -- and needs to be repeated monthly over at least three months, because of the length of time it takes for the worms to mature.
- VeterinaryPartner.com: Whipworms
- Veterinary Notes For Dog Owners; Trevor Turner
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