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Dog Parasites - Preventing, Diagnosing, & Treating Dog Parasites

How old does my dog need to be to start parasite prevention?

Ideally, your dog should start parasite prevention at two weeks of age, and they should be wormed every two weeks until they're six to eight weeks old, when they can begin a monthly preventative program to keep them worm-free.


Dr. Mitch McKee
Cupola Animal Hospitals - Berry Farms Animal Hospital

What's the difference between internal and external parasites?

So internal parasites are parasites that live within the body. We're talking about roundworms, hookworms, and whipworms. These are parasites that are pretty common for puppies and can be common to many dogs that spend a lot of time outside. These worms are in the environment. They're easily picked up through the soil or from contaminated sources. They can cause some pretty severe diarrhea, weight loss, and sometimes anemia because some of these worms attach themselves to the inner lining of the intestines and feed on the blood there. There are also tapeworms, which are sometimes transmitted by having fleas. And there are other sources of contamination, such as stagnant ponds or creeks that may have parasites like Giardia that they pick up by drinking the water. A lot of these can cause diarrhea, vomiting, and weight loss. So those are internal parasites or the kind of parasites that primarily affect the GI system.

External parasites are the ones that we're going to find on the outside of our bodies. We're talking about fleas, ticks, lice, and different kinds of mites. And those typically cause skin irritation or some chronic skin problems, but that would be the difference between those types of parasites.

How soon should I bring my dog to the vet if I suspect they may have parasites?

As soon as you notice, particularly if you're finding worms or worm segments in the fecal matter, you want to let your vet know so that they can get the appropriate treatment. If you find ticks or fleas, or if your cat or dog is scratching a lot, especially around the ears, it's always a good idea to get checked for some of these things.

How will a vet diagnose parasites in my dog?

Usually, internal parasites are going to be diagnosed by some type of fecal exam. There are different ways of doing that. It can be done in-house or sent out to the lab. Some other tests can be done to identify these that mainly involve looking at slides under a microscope and seeing what eggs might be there. If you're to a certain point where you're sort of past the egg phase and your dog has adult worms in their stool, then we can look at the worm and identify it that way as well. But most often, for internal parasites, we're looking at some type of fecal sample. For external parasites, it's mainly visual, involves, or having some skin issues, which will sometimes prompt us to check for certain types of mites.

Is ringworm a parasite?

So the name ringworm can be a little bit confusing, but it is not a parasite. It is called ringworm because if you have it or if your pet has it, it tends to make a circular ring on the body. But ringworm is a fungus. So it's not a parasite, but it's something that can be very irritating to the skin and contagious as well.

Why is early detection and diagnosis of parasites so important?

Well, what we know about parasites is the longer they're around, the more damage they can do. So if we can prevent them from being there a long time, especially in regards to ticks and tick attachments, there are certain windows of time where diseases can be transmitted. If we can interact in that specific window to avoid that from happening, perhaps we can prevent some disease process. And having parasites living within your body can cause some pretty long-term issues, such as not gaining weight or thriving as you need them to. So early prevention and detection are essential because it benefits the long-term wellbeing of your pet.

If you still have other questions and you'd like to reach out to us, you can call us directly at (615) 224-7776, you can email us, or you can reach out on Facebook. But please do reach out, and we'll get back to you as soon as we can.

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