Pet Parasites

Are Your Pets Protected?
Amberly Pearce

There are six types of intestinal parasites most commonly seen in dogs and cats. The most used way of testing for these parasites is with an intestinal parasite screen. This test requires a small amount of fecal material to look at under the microscope.
The six common types of intestinal parasites are:

Roundworms: The adults live in the small intestine and the eggs are passed in the stool. Animals are infected by ingestion of other infected animals (ex. rats), fecal-oral transmission, or, by pre-natal infection. Eggs are passed in the stool 3 weeks after infection. Infection with roundworms can cause poor hair coat, diarrhea, ill-thrift, pot-bellied appearance, and sometimes a secondary bacterial pneumonia. Worms can sometimes be vomited up or seen in the feces.

Hookworms: These worms are most commonly seen in young dogs and cats. Adult worms live in the small intestine. Animals become infected with hookworms by eating infective eggs or larvae; penetration of footpads or skin by larvae; transmission through the milk while nursing; or, transmission from the mother into the fetus while still pregnant. It takes three weeks from the time of infection until eggs are passed into the stool. Hookworm infection can cause a severe and sometimes fatal anemia in the young, weak, or malnourished animals. Clinical signs are weight loss, diarrhea, and bloody, tarry stools. Sometimes the worms are seen in the feces.

Whipworms: Adults live in the large intestine and eggs are passed in the feces. Diagnosis can sometimes be difficult because whipworms are not prolific egg-layers. Infection is via fecal-oral transmission. Eggs do not appear in the feces until 3 months after infection occurs. Clinical signs that can be seen are weight loss and diarrhea, which may or may not have blood.

Tapeworms: Adult tapeworms live in the intestine of dogs and cats. Tapeworm is obtained by eating infected fleas or can be transmitted by eating infected mammals such as rats. Diagnosis is by visualization of the small, ‘rice-like’ segments in the stool, or seeing the eggs on a parasite screen. The eggs and worm segments are inconsistently shed in the feces. A negative intestinal parasite screen does not completely rule out the possibility of tapeworm infection. Clinical signs are rare since tapeworm infection rarely causes a problem. Some clinical signs can be unthriftiness, shaggy coat, irritability, diarrhea, or lethargy.

Giardia: This parasite lives in the small intestine. Infection is via the fecal-oral route. The incubation period is 1-2 weeks. Clinical signs can be inapparent, continuous, or persistent with diarrhea and weight loss.

Coccidia: Transmission is fecal-oral and usually due to unsanitary conditions. It is commonly seen in the young and immune suppressed animals. Clinical signs can be inapparent or entail weight loss, lethargy, and a mucoid diarrhea, with or without blood present.

Not only can these parasites cause problems for our pets, but many of the larvae can penetrate human skin and can cause skin and organ problems. It is recommended that no one goes around barefoot for 5-7 days after treatment to prevent infection.