Endoparasites are internal parasites that can be found in various organs and tissues of an animal's body. One area commonly targeted is the intestines.
While there are others, three of the more common intestinal parasites that affect our companion animals are roundworms, hookworms, and tapeworms.
How do dogs and cats contract intestinal parasites? Infection can occur through a number of possible routes, depending on the parasite species. Remember that different stages of the parasite's life cycle can play a role in transmission.
A primary route of infection is ingestion of infective eggs from the environment. Typically this happens when a dog or can ingests fecal matter or soil that contains fecal matter.
Another possible mode of infection includes ingesting an infected intermediate host; this will typically be a prey animal, such as a bird or mouse. In the case of tapeworms, a very common way for a cat or dog to become infected is to swallow the intermediate host, a flea, during grooming.
The larval stages of some parasites are capable of penetrating the skin. This is one method by which hookworm infection occurs.
Kittens and puppies may also contract the parasites while developing inside the mother, or postnatally by ingesting the mother's milk. The majority of puppies and kittens acquire roundworm infections from their mothers.
Roundworms are the most common of the parasitic worms found inside a cat or dog. Almost all cats and dogs become infected with them at some time in their lives, usually as kittens and puppies. The adult roundworm lives in the host's intestines.
How will you know when an animal has a roundworm infection?
You may observe adult worms in the feces or vomit…looks like little pieces of spaghetti wriggling around.
The intestinal disruption may cause diarrhea, constipation, or vomiting.
An animal suffering from a heavy intestinal parasite infection may also exhibit signs of impaired growth and malnutrition. This could include poor growth without a decrease in appetite, or can include a pot-bellied appearance from the worms.
The hair coats of infected animals can often grow dull and unhealthy-looking, due to the nutritional deficit being caused by the parasites.
The hookworm attaches to the lining of the intestinal wall and feeds on the host's blood. The worm also releases an anticoagulant at the site of attachment to increase blood flow.
For hookworm infections, you may see adult worms in the feces or vomit. The signs can also reflect moderate to severe blood loss, because hookworms will cause bleeding into the intestinal tract resulting in internal blood loss. Signs of intestinal blood loss can include black, tarry stool. These animals are also prone to anemia.
Blood loss from severe hookworm infections may cause death in young kittens and puppies.
Adult cats may also suffer blood loss from hookworms and can have diarrhea and show weight loss.
Tapeworms are long, flat worms that attach themselves to the host's intestines.
A tapeworm body consists of multiple parts, or segments, each with its own reproductive organs. These segments are called proglottids.
Tapeworm infections are usually diagnosed by finding proglottids —which appear as small white worms that may look like grains of rice or seeds—on the rear end of the animals, in the feces, or where the animal lives and sleeps.
A healthy animal with a moderate tapeworm infection may show no outward signs, but heavy or chronic infections can lead to a dull coat, decreased appetite, and weight loss.
There are several different species of tapeworms that may infect our animals, each with different intermediate hosts. Because fleas are an intermediate host for the most common kind of tapeworm, if a dog or cat has fleas there's a good chance that she also has tapeworms.
Signs of a parasite infection may not always be outwardly apparent. That's why it's always a good idea to include a fecal examination as part of routine veterinary care. By examining the feces under a microscope, veterinary technicians can detect the eggs of intestinal parasites….such as the roundworm egg seen here.
If your dog or cat has intestinal parasites, you'll want to consult your veterinarian for safe and effective treatment options. Some over the counter products can cause cramping and other discomforts, and can carry severe risk when used with animals that are too young, too old, or debilitated. The products available through veterinarians are safe and convenient, and often protect against multiple types of parasite.
Keeping our animal's surroundings clean, and keeping them out of contaminated areas will go a long way in preventing parasites. There are also several convenient preventive medications available for intestinal worms. It is highly recommended to always use an FDA-approved product that is recommended by your veterinarian; some over-the -counter products have been shown to be less effective and to even cause harmful side effects. Furthermore, many of the products approved by veterinarians have the convenient feature of preventing more than one type of parasite.
