Intestinal Dog Parasites

Intestinal dog parasites are worms or microscopic parasites which live in, or feed on the intestines of a dog. There are many kinds of intestinal parasites, many of which produce similar symptoms. Most can be treated quickly and successfully, but there can be dangers associated with certain long-term parasitic infections.


Roundworms can be spread by ingesting infected eggs from soil or grooming, or by eating an infected rat, rabbit or other rodent. These worms can also be passed from mother dog to puppies during pregnancy or nursing. Roundworms are long, white and look like cooked spaghetti. Infected dogs will usually experience diarrhea and vomiting. Occasionally, a roundworm of up to 7 inches long will be present in the vomit. Left untreated, a roundworm infection can lead to a pot-bellied appearance, pneumonia or intestinal obstruction.


Hookworms feed on blood by attaching hook-like appendages to the intestinal walls. This parasite is passed in similar ways as roundworms, and additionally larvae may potentially penetrate a dog's skin. Hookworms leave behind an anticoagulant at the site of attachment. If they disconnect and reattach at another location, the initial spot may continue to bleed leading to serious diarrhea, anemia or even death in dogs.


The eggs of a whipworm are passed in the feces and can therefore be consumed by normal grooming and licking habits of dogs, or by consumption of contaminated food or water. These intestinal parasites are so named due to their shape; being broader at one end like a whip. Small numbers of this worm may produce no symptoms, but larger infections may cause weight loss, anemia and intestinal inflammation. 


The most common intestinal dog parasite is the tapeworm. Tapeworms are contracted by ingestion of an infected flea and are long, flat and segmented. They can grow to be over 6 feet long. Often, live segments of this parasite can be seen in the feces or stuck to the hair around a dog's anus. Scooting due to irritation may also occur. Tapeworms can easily be treated and often no other symptoms or long-term side effects will occur.

Microscopic Intestinal Parasites

There are other forms of intestinal parasites that can cause problems in dogs. The most common of these are coccidia, giardia and strongyloides. Natural immunities are generally in place to prevent long term effects from infection by these microscopic organisms. Puppies, dogs with suppressed immune systems, or dogs that are experiencing stressful conditions are at a greater risk for serious side effects. As with most other parasites, these may be contracted by consuming contaminated water or exposure to infected feces. Dehydration, vomiting, diarrhea, bloody stool and death may occur in high-risk animals.

Treatment of Intestinal Dog Parasites

There are drugs and medication on the market to prevent and cure all major types of intestinal parasite infections. For worms, products are available for the simultaneous prevention and elimination of numerous types. Due to the similarities among symptoms, diagnosis will often require simple tests to determine the cause, and to rule out additional possibilities of infection and disease.