Dog worms the wriggly details
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When an owner comes into the clinic to exclaim that their dog is infested with worms (usually means that they've found them wriggling in the poop), generally it means they've found roundworms. Roundworms are the most common and most puppies will have the odd roundworm or 2 some time in their lives. Other worms that can be found in poop (usually referred to as rice grains moving in the poop) are tapeworms and can be found in young and older dogs. The other worm that can sometimes appear in poop are whipworms but these really only appear if the puppy has had a severe infestation.
The only real way of checking for possible worm infestations apart from the finding a live one in the poop is with a poop sample that your veterinarian looks under a microscope. There we check for worm eggs which aren't usually visible to the naked eye. Some dogs can have worms with no overt signs but if the infestation is severe enough, usually you'll find the dog isn't thriving, has a pot belly, with the usual diarrhea (with or without blood) and occasionally they'll also be vomiting.
Most commonly seen in puppies but can self-activate if present in pregnant bitches in readiness to infect the newborm pups. Puppies with roundworms live in their intestines giving them a pot-bellied appearance. Their presence in the intestines results in poor food absorption and these puppies usually fail to thrive. In some extreme cases where there are lots of worms, they can actually clog up the intestine and cause death. You are also likely to see the worms in the vomit or poop of affected puppies.
An adult worm can grow to seven inches long. Roundworms are prolific and can produce up to 200,000 eggs daily. The eggs are shed in the poop of dogs and due to their hard casing, can exist in soil for years. Infection occurs when dogs ingest the worm eggs. These eggs then hatch in the dog's intestine and the larvae enter the bloodstream for a sidetrip to the lungs. Once there, the larvae crawls up the trachea and the dog then swallows it. This process can cause puppies to cough so you can sometimes find them coughing little worms up. Any larvae that gets swallowed then continue growing in the dog's intestine. Adult dogs don't usually have roundworms. The exception is in pregnant bitches where roundworm larvae can live in a suspended state in the body and then reactivate late in pregnancy to infest new born puppies.
Most dewormers in the market will target roundworms. It must be noted that worming the pregnant bitch doesn't seem to help ie they seem to still activate despite it which is why most breeders will worm puppies routinely.
Often hard to pick them, if only because they aren't usually present in large numbers. They look like skinny bits of thread but are so small it's hard to pick with the naked eye. Whipworms live in the dog's large intestines and produce eggs only sporadically, unlike roundworms who produce eggs in copious amounts. This is why it's often difficult to diagnose because several fecal samples may have to be taken to find the eggs in the poop. Because whipworms attach themselves to the intestinal walls and feed, they cause intestinal bleeding. Puppies with whipworms are often anemic (therefore have low energy) and have diarrhea with blood in the poop.
Hookworms can affect a dog at any age. It's similar to whipworm in that it hooks onto the intestine and sucks blood resulting in anemia - which results in a lethargy, pale gums, diarrhea with blood. Hookworms are not visible to the naked eye so vets usually make the diagnosis based on finding the eggs in a poop sample.
Hookworms can be transmitted to humans by penetration of the skin - so walking barefoot over infected soil can result in hookworm infestation. Humans infected with hookworms have similar symptoms - ie bleeding in the intestines and diarrhea.
If you look at a tapeworm under the microscope, you will know where it gets its name from. Tapeworms have a long, flat appearance - like a tape with segments that break off. Owners often report of moving grains of rice on their dog's poop and these are tapeworm segments. Whilst heavy infestations of tapeworms result in vomiting and weight loss and sometimes itching around the anus, most dogs with mild infestations show no overt signs at all. Tapeworm segments contain eggs which need to be ingested by flea larvae first before it can re-infest a dog. By the time the flea is an adult, the tapeworm is ready to infect a dog or cat. Dogs ingest fleas whilst grooming themselves, once inside the dog, the flea gets digested and the tapeworm inside the flea gets released into the intestine and the cycle starts again.
Problem with tapeworms is that not all deworming medication targets tapeworms. Read the labels of your dewormers (which will tell you if they cover tapeworms as well) to ensure that your dog is properly covered.
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