Parasites in Puppies – Round Worms

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By Tess Thompson



There are five types of intestinal worms in dogs that infect canines of all ages.

Roundworms mainly affect puppies. Out of the two species of roundworms, Toxocara canis and Toxascaris leonine, the former is more prevalent in dogs than the latter. They are about 2 cm long when they enter the intestines of a dog. But within a matter of ten days, they grow to a length of 6 cm. The adult roundworm lives in the small intestines of a dog. There are different paths that the roundworm can take to finally reach the intestines.

In the case of puppies, the roundworm infection is passed to the young puppy while he is still in the uterus. During their lifecycle within the body of a dog, all roundworms do not get to reach the small intestines. Some larvae get embedded in the tissue and remain dormant for long periods that can extend up to many years. When a female dog becomes pregnant, the roundworm larvae spring back to life from their dormant state, find their way to the uterus through some inexplicable process, and burrow their way into the fetus. This leads to infection in the fetus and within two weeks of birth, the puppies are fully infected with adult roundworms in their intestines.

Another way in which puppies and young dogs can get infected with roundworms is similar to how adult dogs get infected. This is by ingesting infected larvae directly from the environment. Puppies tend to get infected from the mother’s own feces.

Although the symptoms of worms in dogs and feline parasites are general in nature, severe infestation can prove to be fatal in puppies. Puppies that are severely infested show signs of a swollen belly. Roundworms curb growth and negatively affect the quality of the coat in young puppies. One of the most serious conditions that roundworms lead to is through heavy infestation. In such cases, the roundworms coil up and entangle themselves to obstruct the passage of the intestines.

De-worming of puppies should start as early as two weeks after birth. Normally, breeders are aware of the risk of roundworm infection in puppies. As dog owners prefer to purchase puppies and not adult dogs, it is necessary to get all the information about the de-worming regimen that needs to be followed. The fact that even after treatment some roundworm larvae are likely to remain dormant in the body makes it important that treatment be continued well up to nine weeks.

Puppies normally develop resistance to new infections after reaching the age of about six months. There is no reason that your pet should get re-infected if you take proper preventive care for de-worming in the early stages by keeping the environment clean.

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