Roundworms in Dogs and Cats

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Roundworms in Dogs and Cats

Roundworms are a common intestinal parasite seen in both dogs and cats. Puppies and kittens are often born with a developing roundworm infection that can lead to stunted growth if not treated properly. Read on to learn about this very common condition.

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What are roundworms?

Roundworms can infect both cats and dogs. Toxocara cati are roundworms that affect only cats and kittens, while dogs and puppies are affected by Toxocara canis. Both dogs and cats may be affected by Toxocara leonina. Adult roundworms are relatively large and can grow up to 7 inches in length. They are typically white-cream in color and are often described as looking like spaghetti.

How did my pet get roundworms?

There are several routes of transmission:

  • Trans-mammary Transmission - Nursing from an infected mother (puppies and kittens)
  • Trans-placental Transmission - While in utero (before birth) from an infected pregnant mother (puppies only)
  • Ingesting roundworm eggs from the soil, usually when grooming or self-licking
  • Eating infected prey, such as rodents

Signs Your Pet May Have Roundworms

  • Stunted growth in puppies and kittens
  • Bloated and/or painful abdomen
  • Diarrhea
  • Worms present in vomit or stool
  • Sometimes pets display no signs

Diagnosis of Roundworms in Dogs and Cats

  • Worms visible in stool or vomit. Worms may potentially be alive and moving.
  • Definitive diagnosis is made by the presence of roundworm eggs on microscopic exam of stool (fecal analysis).

Treatment of Roundworms in Dogs and Cats

Puppies and kittens should be dewormed as part of routine veterinary care. Several medications are effective in treating infections. Typically, multiple doses are necessary to fully eliminate roundworms.

Many monthly heartworm preventatives also contain deworming medication that is effective in eliminating a variety of intestinal parasites. Veterinarians recommend providing your pet with year-round heartworm prevention.

It is always recommended to bring a stool sample to your pet’s yearly veterinary wellness exam.

Preventing Roundworms in Dogs and Cats

  • Routine (yearly) fecal exam
  • Monthly heartworm preventative
  • Cleaning up your pet’s stool from the environment as soon as possible. Fresh stool is not infectious. It takes about four weeks before roundworm embryos can cause infection. Eggs can remain infective in soil for years.
  • Prevent pets from hunting

Can I get roundworms?

Yes! You and your family can become infected. People can contract a roundworm infection by accidentally ingesting soil that contains infective eggs.

Ingesting large numbers of eggs can lead to liver, skin, or eye issues. Removing stool from the environment, covering sandboxes and hand washing are all effective methods to help prevent roundworm infections for you and your family.

Read more:

Hookworms in Dog and Cats

Deworming Your Dog - Q&A

Common Intestinal Parasites in Cats

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Published: 6/11/2021
Last updated: 8/9/2021

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