When it comes to keeping your canine companion healthy both inside and out, it’s important for owners to understand the variety of parasites that see your dog as the perfect host.

Let’s talk about one of the lesser-known parasites that nonetheless pose a danger to dogs: whipworms. Whipworms are resilient creatures, and in egg form, their hard shells allow them to survive outdoors in the soil for years in the time. In many ways, whipworms are similar to hookworms, but instead of ending in a hook shape, one end of this worm tapers to a narrow point, like a whip.

Unlike hookworms, whipworms can’t enter the body through the skin. The only way for your dog to contract them is by ingesting the eggs. Whipworms are widely distributed throughout North America, and transmission is a simple matter if your dog has any contact with other dogs. The long-lived eggs can show up in the soil, shared dog toys, discarded bones and water dishes. Once ingested, whipworms then grow to maturity inside your dog’s digestive system.

Once inside and having reached maturity, the adult worms fasten themselves to the large intestine and the cecum, a transitional pouch between the large and small intestine. Here, they slash and puncture the intestinal walls in order to feed. The female starts to lay her eggs, which are then excreted through the feces.

Symptoms for whipworm resemble those for other worms, such as hookworm. Many dogs carry a certain number of whipworms without manifesting any problems, but past a certain point, your dog may begin to exhibit symptoms such as a dull coat, anemia, rapid weight loss, and a loose and bloody stool. He may also begin vomiting up a yellow-green substance. In very severe cases, the worms may begin to puncture the intestinal wall, to the degree that the intestine begins to stick to the body wall. In this case, you might see your dog licking and worrying his right flank.

When you take your dog to the vet, it may take some time to positively diagnose him with whipworm. Whipworms lay eggs only intermittently, and even when they’re actively releasing eggs, the presence of diarrhea in your dog can make the eggs difficult to find. Typically, vets will perform four stool samples over four days before they will rule out a possible whipworm infestation.

If whipworm eggs are found, your vet will administer a potent dewormer. However, all whipworm dewormers on the market are only effective against worms in their adult form. As a result, re-treatment will probably be necessary.

There are no simple and effective ways for removing whipworm eggs from the soil around your house. However, a contaminated environment can infect your dog over and over again. The best way to fight against reinfection is to make sure your dog’s quarters are sunny and dry, since whipworm eggs require moisture to thrive. Try to place him in an area of fresh new gravel, pavement or soil.