Many parasites can take up residence inside your pet: roundworms, hookworms, whipworms, tapeworms, heartworms and more. Left uncontrolled, these parasites do their dirty work by consuming the nutrients your pet needs by preventing their body from properly absorbing those nutrients. They also destroy red blood cells, cause anemia, damage or kill tissues and cells as they move through the body and transmit disease.

Roundworms (Ascarids) are the most frequent worm parasite in dogs and cats. There are two species that commonly infect dogs: Toxocara canis and Toxascaris leonine. Adult roundworms are extremely hardy and live in the stomach and intestine, growing up to seven inches long. A female may lay 200,000 eggs in a day. Puppies with roundworms look thin and scrawny, except for their distinctive potbelly, and they may vomit frequently or have diarrhea. A rough, dull coat is another sign of roundworm infestation. Pups with a heavy load of roundworms may develop a cough or even pneumonia.

Hookworms (Ancylostoma) are most common in warm, humid climates and thrive in warm, damp, sandy soil. Hookworms are small, thin worms about one-quarter to one-half inch long. Small hookworm larvae penetrate the skin, usually through the feet, or are transmitted to pups through their mother’s milk. They can also be ingested from the environment, such as off a blade of grass. They fasten their mouth onto the mucosa of the small intestine and suck blood and tissue fluids from the host. This can result in severe blood loss and malnutrition.

Whipworms are acquired when a dog eats something that has been in contact with contaminated soil or infected larvae. The adult worms live in the last part of the small intestine and the first part of the large intestine, where it fastens to the wall of the gut. Whipworms can cause acute, chronic and intermittent diarrhea in dogs. Typically the stool has mucus and is bloody. The diarrhea is often accompanied by urgency and straining. Dogs with heavy infestation may lose weight, fail to thrive and develop anemia.

Tapeworms look like long, flat ribbons. The most common tapeworm found in dogs is called Dipylidium caninum, which is spread by fleas or lice. Several species of Tania, another type of tapeworm, may also parasitize dogs. Taenia is acquired by eating infected rodents, rabbits and sheep. A dog must bite or swallow an infected flea or louse to acquire the parasite, then the tapeworm uses hooks or suckers on their heads to attach themselves to their host. The body of the tapeworm is composed of segments which are a quarter-inch long and look like white rice, can sometimes be seen with the naked eye, crawling on a dog’s rear end or in the bedding or stool. To cure the tapeworm infection, the head must be destroyed. If it is not, the worm will regenerate.

Heartworm Disease is a serious and potentially fatal condition is caused by the parasite Dirofilaria immiti. It’s commonly known as heartworm because it takes residence in the heart and major blood vessels of dogs, cats and other mammals. Heartworms are spread by mosquitoes, so they’re found throughout the world. Signs of heartworm disease vary, depending on how many worms the dog is carrying. Dogs with few worms may not show any physical signs, but if the infection is heavy, the dog may be lethargic, lose weight, cough during exercise or even pass out after exertion. Dogs with severe cases may suffer from congestive heart failure.

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The materials, information and answers provided through this website are not intended to replace the medical advice or services of a qualified veterinarian or other pet health care professional. Consult your own veterinarian for answers to specific medical questions, including diagnosis, treatment, therapy or medical attention.

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