Intestinal Parasites

You asked me to bring a fecal sample, Doc.  What are you looking for in my pet's poop, anyway?!

A common request to our clients is to bring a fresh sample of feces from their pets to an appointment to be tested.  Many of you are probably wondering what, exactly, we are looking for in that smelly sample!  We're looking for intestinal parasites.  There are many types of intestinal parasites we may find in your pet's feces, and not all of them are worms.  Here we have listed the most common types of parasites in dogs and cats, and their importance to your pet and the rest of your family. 

Most of the time we are checking a fecal sample, we are not looking for adult worms.  Instead, we prepare the sample and place it under a microscope to find worm eggs.  In some cases, the parasite is a single celled organism (protozoa) which is very different from a worm.  Intestinal parasites have many symptoms, ranging from no symptoms at all, to severe diarrhea, or even fatal anemia.

Unfortunately, our fecal sample tests are not 100% accurate.  Intestinal worms only shed eggs into the feces intermittently, and protozoan organisms can be very difficult to find.  For this reason, we often recommend medications for deworming of dogs and cats, even if we do not find parasites.  This is especially important for puppies and kittens.  We may also recommend multiple fecal sample tests, to increase the chance we will find parasites if they are present. 

 

 

 

Roundworm eggs under a microscope

Roundworms

Roundworms are very common in puppies and kittens, and can affect adult dogs and cats as well.  They can be transferred to puppies and kittens through the uterus from the mother, or they can be contracted from the environment after birth.  The adult form of this parasite is a long white worm that can look like a piece of spaghetti.  You may see these worms in your pet's feces yourself, and they are sometimes vomited.  It is often the cause of the "potbelly" appearance some puppies and kittens have.  This parasite can be transmitted to humans as well, especially children, through the fecal-oral route.  Frequent handwashing is important to prevent the spread of this parasite to your human family members.

Hookworm egg magnified

Hookworms

Hookworms are also common in puppies and kittens, as well as adult dogs and cats.  They are spread in much the same way as roundworms.  However, the adult worm is not visible to the naked eye.  You are not likely to see this type of worm yourself.  Hookworms latch on to the lining of the intestines and suck blood.  They are a common cause of anemia in puppies and kittens.  A large load of hookworms can be fatal to your young pet.  This parasite can be transmitted to humans through burrowing of larva through the skin, or fecal-oral transmission.  Migration of the hookworm larva in humans can cause skin rashes and even blindness.  This is especially important in children.  Again, frequent handwashing and appropriate hygeine is important to prevent the spread of this parasite. 

Whipworm egg

Whipworms 

Whipworms are common causes of diarrhea in young and adult dogs, and less frequently in cats.  Sometimes it is very difficult to diagnose whipworms, as they are notorious for shedding only low numbers of eggs in the feces, and they shed them infrequently.  Whipworms live in the cecum and colon, and even the adult worms are very tiny.  You are not likely to see adult whipworms with the naked eye.  This parasite is not transmissible to humans, but is an important cause of chronic diarrhea in dogs, due to the difficulty in finding the parasite during fecal testing.

Rare tapeworm egg under microscope

Tapeworms 

Tapeworms are long, segmented worms usually spread by fleas.  Dogs and cats with a flea infestation will groom fleas from their haircoat, which will in turn infect their intestines with tapeworms.  Cats that hunt small critters such as mice can also contract tapeworms through the consumption of the prey they catch.  Tapeworm eggs are almost never found during fecal testing.  You will know your pet has tapeworms if you see the tiny white segments from the worm under your pet's tail, or on your pet's feces.  They often look like grains of rice, and sometimes move.  These parasites are not directly transmissible to humans.  

Tapeworm segments - like grains of rice

 

 

 

Coccidia Oocysts

 Coccidia

Coccidia is a type of protozoal parasite that commonly causes diarrhea in puppies and kittens.  It may cause vomiting as well.  Adult dogs and cats can be infected with this organism, but do not usually show symptoms of disease.  It requires medication that is different from common dewormers.  It is not transmissible to humans.

Giardia Trophozoite

Giardia

Giardia is also a type of protozoal parasite.  It causes very watery diarrhea, that can lead to dehydration.  Any age of pet can be affected with this parasite.  Hikers and backpackers are familiar with this disease, as the organism can be transmitted through poorly filtered water.  This parasite is notoriously difficult to find during standard fecal testing, and is becoming more common as a cause of diarrhea in dogs.  Special testing is often ordered to determine if a patient has been infected with this parasite.  Treatment often requires medication different from normal deworming protocols. 

As you can see, the diversity of intestinal parasites in our pets is remarkable.  It is important to have fecal samples checked on your pets on a regular basis, and especially if diarrhea develops.  To decrease the chance of an infected environment, pick up and dispose of your pet's waste immediately.  Monthly parasite prevention with an approved heartworm preventative will usually help protect your pets against hookworm, roundworm, and sometimes whipworm infection.  

Remember that every pet is different, and as common as parasites are, they are not always the primary problem.  Seek the advice of your Noah's veterinarian if you are concerned about your pet.