Roundworms in Cats and Dogs | Pet Quest

Roundworms in Dogs and Cats

Roundworms are nasty parasites that are transmitted through fecal-contaminated soil and water to all living animals as well as humans. It lives in hosts of all ages which makes it a really serious problem for young pets and our children. The good news is that roundworms can be avoided with a monthly preventative. They are also easily treated with deworming medication.


Roundworms | Pet Quest

Roundworms are an extremely common parasite that live in the intestines of puppies, kittens, dogs, cats, and occasionally people. There are many species of roundworms and they can grow quite large (up to 7 inches in length) and can cause severe illness in those infected with them.

These parasites can be passed on from mother dogs to their puppies in the uterus or through their milk while nursing. Cats do not infect their kittens in the uterus but do pass the worms on through their milk.

The adult roundworm lives in the intestines of animals and people where they reproduce and lay eggs. Whenever an infected host passes it feces they will also shed the roundworm eggs. This is when other animals can become infected by having contact with the contaminated feces or ground where the feces are deposited. Animals that eat prey can also become infested with roundworms if the prey has them as well.

Once the roundworm eggs have been eaten they will pass through to the digestive tract. Eventually these eggs will begin to hatch and migrate into the liver and lungs. Once they reach the lungs animals will usually develop a cough. As the animal coughs up these larvae they inadvertently swallow them. Once swallowed the larvae will enter the stomach and then pass into the intestine. Here they will grow and reproduce and the cycle of infestation begins again.

Roundworms are zoonotic parasites. Such parasites can live in animals and humans. Those at the highest risk of infestation are children. Children can become contaminated at playgrounds, beaches, and backyards that are frequented by pets and other animals.

Roundworm infestation in humans can cause several types of larva migrans. This is an illness that is caused by the migration of young roundworms through body organs such as the liver, lungs, and nervous system. The young worms may also migrate to the eye which may cause blindness. This is called ocular larva migrans which occurs all over the world. Especially in developing countries with poor sanitation.

Households that have children and pets should have their pets tested annually for roundworms. Using a monthly heartworm preventative that also controls roundworms and other parasites is strongly recommended. It is also advisable that all people wash their hands after handling pets or going to the beach, playground, or their backyards. Sandboxes should also be covered when not in use to help discourage cats from using them as litterboxes.

Signs and Identification

Roundworm Infection Cycle | Pet Quest
The infestation cycle of roundworms in dogs and cats.

Animals that are severely affected with roundworms are puppies and kittens. They will often look potbellied. Other signs may include:

  • Coughing
  • Dull, thin coat
  • Vomiting
  • Diarrhea
  • Failure to gain weight

Veterinarians can diagnose a roundworm infection by finding microscopic roundworm eggs on a fecal exam. Unfortunately, some owners discover that their pets are infected when live roundworms are expelled in vomit or feces.

Treatment of Roundworms

Cat Roundworm Life Cycle | Pet Quest
Roundworm Life Cycle


Most veterinarians will routinely treat young pets with an antiparasitic medication. They will do this several times during the first year or two of the animals life which interrupts the worm's life cycle. Later on the veterinarian will place the animal on a monthly heartworm preventative that also controls roundworms and other intestinal parasites.

The eggs of the roundworms are not always apparent in fecal material from infected pets. Because of this it is advisable that you deworm your puppies and kittens even if a fecal test does not confirm a roundworm infection.

Usually the whole deworming process is carries two or three times with young animals or to clear up an infected animal. The veterinarian will usually ask you to provide a fecal sample about every two or three months during the treatment process until it is resolved.

Prevention or Roundworms

Roundworms | Pet Quest

Roundworm eggs can remain active in the environment for several months to many years. For this reason it is very important that pet owners clean up and dispose of pet feces immediately. They should never be placed in a garbage bin. Instead, they should be taken home and flushed down the toilet.

It is also advisable that you keep your pet on a leash so as to reduce exposure to areas that may have been contaminated by other animals. This will also help to minimize the chance that your dog or cat will eat infected rodents and birds.

It is best to keep cats indoors to prevent them from hunting infected prey.

Keep litterboxes clean at all times. Especially if you have more than one cat or animal that uses it. This is a major source of domestic infestation which usually occurs when you introduce a new animal to the household. It is best to have any new animals tested for roundworms and other internal parasites before being introduced to your household.

Always consult a veterinarian about the best ways to protect a pet and its human family against intestinal parasites. A monthly heartworm preventive that includes medication for roundworms is a good start for year-round protection from these parasites. Since it’s easy to forget a monthly treatment and no parasiticide is 100 percent effective, periodic fecal exams are still recommended to ensure that a pet remains parasite free.

10 thoughts on “Roundworms in Dogs and Cats

  1. You created some decent points there. Must say that I did check up on this topic with Google and found that you were quite accurate. Really great article. Mr. 229574

  2. I thought that once you had your puppy dewormed that parasites would no longer be a problem. Check on the Internet and I was surprised to see that animals can get parasites all their lives.

  3. There are really great preventative meds that your vet can prescribe. I just don’t understand why people don’t protect their pets against parasites. Don’t they realize that many types of parasites can actually kill their pets?

  4. It still amazes me that with all the medical advances in veterinary sciences that animals can still get these parasites. You would think that we would have eradicated them by now as we have with most human parasites.

Leave a Comment

Do NOT follow this link or you will be banned from the site!
Translate »
Optimization WordPress Plugins & Solutions by W3 EDGE
Read previous post:
Please Don't Scold Me | Pet Quest
Dogs That Have A Low Sensitivity Level

We domesticated the dog a long time ago. And with that we have completely changed their personalities. Once a very...