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Roundworm and your pet!


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These three roundworms are widely distributed throughout the world, and fossil worms have been found in rocks and fossilized tree resins. They live in extreme habitats such as deserts, hot springs, salt water and icy environments. They feed on bacteria and waste and can "hibernate" to survive extremes of heat, cold and drying. They are zoonotic, which means they can infect you and your children.

You don't really need all of the expensive "pooper-scoopers" to clean up after your pet. A simple plastic bag when used like this - left-over from your last shopping trip - will do. Just keep them in an old basket or bucket - or hey - use a larger one to hold the others 'til you need them.

bleach and a broom will help to clean worm eggs upUse 3 cups of bleach to a gallon of water to scrub your kennels and litter-pans each week.




roundworms are whitish and about 4-6 inches long
Roundworms are whitish in color and about 4-6 inches long.

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Symptoms |Getting rid of Them

What are Roundworms?
by Dr. N.J.Hayes, DVM

Roundworms are one of a group of internal parasites of puppies, kittens, dogs and cats. There are more than 15,000 known species of roundworms, with thousands of individual nematodes in a handful of garden soil. Most are zoonotic. They are members of the nemathelminths group of animals. Other members are hookworm, whipworm, pinworm and tapeworm.

We, however, are mainly concerned with the 3 roundworm species that infect our dogs and cats. They are Toxocara canis, Toxocara cati and Toxocara leonina. The life-cycle of each of the 3 species is slightly different.

T. leonina can infect both dogs and cats and has the simplest life cycle. The dog or cat ingests the eggs. The eggs hatch and mature in the small intestine. Then the male and female mate and she lays up to 200,000 eggs that will pass out into the environment with the feces. Small rodents may serve as an intermediate host for T. leonina. The roundworm will develop in the rodent as usual; but, if eaten by a carnivore, the larvae will be released in the dog or cat's digestive system and become adults in the intestine.

T. canis and T. cati roundworms have a life cycle that is a little more complex. T. canis & T. cati can infect an animal by ingestion of the eggs, ingestion of an intermediate host, or by larvae passed to the puppies while nursing or in the uterus.

Roundworm eggs need to remain in the environment for several days to a few weeks - depending on weather conditions- before they can infect a new host. The eggs can survive for several months, although they are sensitive to ultraviolet light.

How does my pet get roundworm?

Most dogs and cats will have roundworms at some point in their lives. At any given time, 30 to 50% of dogs and cats are infected and over a million people in the United States are infected by the parasites carried by their pets.

The roundworm larva are so small, they can pass through the placental blood supply and into the fetal lungs or liver. After birth, they travel to the intestine, where they grow. Most puppies are born infected with roundworm from their mother, but kittens don't acquire roundworm in utero. They may become infected from nursing milk that contains roundworm larvae.

As if the possibility of infection before birth isn't enough, the puppies and kittens can become infected by ingesting eggs in the litter box, eating feces, or ingesting eggs in their food or water. It only takes 3 weeks for the worms to mature inside an animal and start laying eggs, so the puppies may infect each other right in the litter box.

After the eggs are ingested and hatch, they migrate through the pet's body by way of the circulatory system that drains blood from the stomach and intestines. They are carried into the lungs, airways and liver where they cause coughing, pneumonia or liver disease. Sometimes the adult pet's immune system detects the intrusion and encases the larvae in a cyst, where it can remain dormant for the life of the host, or it can be reactivated by pregnancy hormones. In puppies, it usually gets coughed up, swallowed, and grows into adult worms in the intestine.

Your pet can get roundworm from walking in the park.Our pets can become infected with roundworms by walking where other dogs have defecated. It doesn't matter what size the dog is; it's the same roundworm, and it will lay just as many eggs to infect the next pet! If they attach to your pet's feet and are ingested while they clean themselves, they'll infect your pet Dogs can also become infected with T. cati while it's "surfing" through the cat's litter box.

We can help prevent spread of the worms in our lawns and public places by picking up the feces while walking our pets and cleaning the litterbox frequently. This will keep the eggs from maturing to the infective stage. Also, keep your children's sandbox covered to keep animal droppings out. Wear shoes when outside and wash your hands thoroughly after working or playing outside.

How do I know if my pet has roundworm? What are the symptoms?

Adult dogs are more resistant to roundworm and may show no symptoms. The greatest danger is to the very young, the very old and to those animals that are immuno-compromised because of illness or malnutrition. Many times, the client learns of the infestation when the puppy vomits some worms out on the floor or passes some in its' stool.

This is a relatively large whitish worm, (around 4-6 inches long and about the diameter of a strand of spaghetti), so worm burden can cause:

  • stomach distension
  • colic
  • poor intestinal function and failure to thrive.

Young puppies and kittens may suffer from:

  • poor appetite
  • malnutrition and weakness
  • stomach distension
  • coughing and vomiting
  • hypothermia
  • apathy and general ill health
  • The feces may be scant in proportion to the food eaten
  • They may have a slow heart rate and occasional diarrhea
  • The coat may become dull, break easily and lack luster.

As the roundworms become adults, they move around in the intestine and eat the nutrients that the pet needs. They eat at the mucous lining of the intestine - causing irritation and pain. Your pet may lay curled up in its' bed whimpering. The pain from irritated intestinal linings can last weeks to months. If the worms are in great numbers, they may block the intestine and cause constipation. They do not latch onto the intestinal wall and eat the pet's blood, as the hookworm and whipworm do.

The migrating larvae are a greater danger to the pet. They can cause pneumonia in the lungs, or hepatitis in the liver. Untreated infestations can cause permanent damage to the organs.

As pets become older, they become more resistant to roundworms and may show no signs. An adult dog or cats immune system will usually recognize the infestation in time to form cysts around the larvae and cause them to become dormant. Pets that are ill or otherwise immune-compromised may become deathly ill.

How do we get rid of them?

There are many treatments to rid your pet of roundworm. These are usually administered on a schedule that allows all of the young, migrating worms to be treated.

The puppies should be tested at time of weaning and on a schedule established for you by your veterinarian. Most veterinarians want to start puppies around 2 weeks and kittens around 3 weeks, with re-treatment in 2 to 3 weeks. After treatment, your veterinarian will probably want to do a fecal check in a few weeks to make sure it's free of worms. The best treatment for roundworm is to get regular fecal tests done.

There are many heartworm preventatives that help immensly to prevent roundworm infestation by killing the larvae on a monthly basis. These will be more effective following a course of treatment to bring the infestation under control. Your veterinarian will recommend treatments that are appropriate to your situation.

It may be necessary to supplement with intravenous fluids if the infestation is too great and the animal shows signs of acute constitutional disorder. Usually, the animal has vomited up some of the worms on the clients' carpet or has a distended stomach that has brought them to their veterinarian in time.

All dogs and cats in the household will need treatment, because they will have contaminated each other by licking each other, play biting, or by walking over ground that has become contaminated and subsequently ingesting the eggs.

It is necessary for the client to fully understand the necessity to keep the feces collected frequently to keep the eggs from reaching maturity after being "laid" and to keep the pet's bedding and environment regularly cleaned.

How can I keep my pets from becoming re-infected?

In a kennel situation, the floors in the runs should be easy to clean and be cleaned frequently. All fecal material should be picked up daily. Use a bleach solution of 3 cups bleach to a gallon of water to mop the kennel each week. It won't kill the eggs, but will remove their sticky surface and make them easier to clean off. There are no chemicals that can eliminate the eggs from your lawn or kennels. Indoor kennels need to be steam cleaned to reduce infection. Contaminated yards can only be treated by removing the soil or turning it over to a depth of 8-12 inches.

It isn't easy to eliminate roundworms in dogs. It requires an agressive treatment program for the pregnant bitches through several generations. Treatment of the bitch before pregnancy - and during - will reduce the number of larvae that the puppies are exposed to.

Eliminating transmission of the larvae from the female cat to her kittens is even more difficult. Since the kittens aren't exposed in utero, but only from the milk, hand-rearing may be necessary. The cages and litter pans should be kept free of feces and cleaned weekly with the above bleach solution. All mice and small rodents need to be eliminated.

Roundworms are zoonotic; however, since humans are not a natural host, the body recognizes the threat early and forms granulomas around the larvae. Unfortunately, the granuloma may occur after the larvae has migrated to the eye or brain and cause interference with the normal function of the organ. This can cause blindness or seizures.

Human infestation can occur from digging in the garden, playing in a contaminated sandbox, touching the pet's feces, or laying a lovely new landscape border around your sidewalk. Other species, such as racoons, also carry rundworm; so it may be in the environment. Careful hand washing is a necessity! For further information about the dangers of roundworm infestation in humans, please go to the Website of the Center for Disease Control and read about zoonotic diseases and roundworm in particular.


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