Symptoms and Treatment of Lice in Dogs

Estimated Reading Time 5 minutes
Symptoms and Treatment of Lice in Dogs

Dog lice are parasites. They are small, flat, wingless, six-legged insects that live on mammals and birds, more specifically on their hair or feathers. They can hang onto the hairs thanks to strong claws at the end of each leg. The good news is that lice are species-specific, meaning that you cannot get them from your dog or vice versa. They survive on skin debris, sebaceous secretions, feathers, and the host’s blood. Keep reading to learn more!

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Types of Lice That Infest Dogs

On dogs, the most common ectoparasite is fleas, but lice can also make their way on their bodies. They can cause itching, inflammation, pain, and hair loss. Unfortunately, all of this can also lead to more severe health issues, which is why it is essential to recognize them and eradicate them as soon as possible.

Two types of lice can infest dogs: chewing lice and sucking lice.

Trichodectes canis and Heterodoxus spiniger are known as the chewing lice. They grip the host’s hairs with large and wide mouthparts and chew on the animal’s dead skin cells and surface secretions. They are characterized by a blunt, flat head. Trichodectes canis can also be a vector for canine tapeworm and live on the host for 30 days.

On the other hand, Heterodoxus spiniger is mainly found in tropical regions and has also been seen on coyotes, red foxes, and gray wolves after an examination.

Linognathus setosus is known as the sucking louse. They grip the host’s hair with claws and suck blood through narrow mouthparts. They are more common in long-haired dogs and colder climates.

There are three stages to a louse’s life cycle: egg, nymph, and adult louse. It starts when a female louse lays tiny yellow or white eggs on the base of the hair shaft. They are glued to the hair and won’t fall off even when you bathe and shampoo your dog.

The eggs hatch in about a week and release the nymphs, which are baby lice. Then, one week later, they enter into the adult phase, and the cycle starts again.

Symptoms of Dog Lice

One way to tell if your dog has a lice infestation is by parting the hair and examining the hair shaft. Adult lice can be seen with the naked eye, and they are the size of a sesame seed (about 2 to 4 millimeters) and yellow or medium brown in color. On the other hand, fleas are very dark, almost black, so you will be able to tell the difference.

Chewing lice move around much more than sucking lice, which like ticks do, embed their piercing mouthparts into the animal’s skin.

Some people may mistake lice eggs with dandruff, but you will know the difference if you shake the dog’s hair, and if small flakes fall off, it is the latter.

Other signs of lice infestation on dogs are:

● Intense itchiness

● Scratching

● Rough and dry coat

● Hair loss (around ears, neck, shoulders, groin, and rectal regions)

● Small wounds

● Bacterial infections

● Restless behavior

● Anemia

● Tapeworms

How will my vet know if my dog has lice?

A dog owner may notice one or several of the symptoms mentioned above. However, a vet can also diagnose lice on a dog by examining the fur or scraping the skin and evaluating it under the microscope. He will be able to determine if it is a case of chewing or sucking lice by looking at the mouthparts and claws.

As we mentioned, the most common places where lice are found on the animal’s body are the neck, head, shoulders, tail, and groin. In addition, they will often be located near skin abrasions or the anus.

How do dogs get lice?

Unlike fleas, lice cannot jump from one host to another. They can’t fly or hop. However, they can crawl, which is why infestation only occurs through direct contact with infested animals, bedding, collars, and grooming tools.

Lice are common in areas where dogs congregate, such as dog shows, daycare, kennels, and parks.

As we mentioned at the beginning of the article, lice are species-specific, so cats and humans cannot get lice from their dogs.

How to Treat Your Dog for Lice

1. Clip matted hair off the dog. Lice and eggs will likely be attached to the hair and hard to dislodge.

2. Use flea combs to remove live and dead lice. After you do so, immerse the comb in water mixed with flea shampoo or insecticide for at least 10 minutes.

3. Use a prescription insecticide medication (topical or oral). Be careful about these products if you have cats, as they may be toxic to them. Ask your vet if they are safe to use on your dog, considering its health, breed, and age.

4. Fur shaving. In severe cases, it may help to completely shave your dog to expose the skin and lice eggs to the topical insecticide.

5. Repeat treatment at regular intervals for one month. You will also need to treat every dog in your household.

6. Wash all bedding, clothing, leashes, and collars. Use hot water and clean all areas where dogs spend time to prevent a reinfestation.

7. It is advised to replace all grooming tools since it can be difficult to remove the eggs from combs and brushes.

Read more:

Symptoms and Treatment of Mites in Dogs

Are ticks dangerous to dogs?

Common Skin Parasites in Dogs

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Published: 9/22/2021

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