Lice on Dogs: Signs, Symptoms, and Treatments

Understanding Lice on Dogs

If your dog or someone in your family has lice, you might worry about how this parasite

spreads. Here’s some reassuring news: humans cannot get lice from dogs, and dogs cannot

pick up lice from humans. Lice are species-specific, meaning the lice that feed on your

dog’s blood won’t switch to humans, and vice versa.

However, lice infestations in dogs can still cause significant discomfort and health issues.

Like fleas, lice can lead to itching, pain, inflammation, and hair loss. In severe cases, they

may result in more serious health problems. Recognizing and addressing lice infestations

promptly is crucial for your dog’s well-being.

What Are Dog Lice?

Dog lice are tiny, flat, wingless insects with six legs, which cling to the hair shafts of

mammals and birds using hook-like claws. These claws are specifically adapted to the size

of the host’s hair or feathers, making lice species-specific. Dog lice feed on skin debris,

sebaceous secretions, feathers, or blood, depending on the type.

There are two types of lice that affect dogs:

1. Chewing Lice

 -Feed on skin debris and surface secretions.

 -Have a blunt, flat head.

 -Two species commonly affect dogs:

 -Trichodectes canis: Found worldwide; typically lives on a host for 30

days.

 -Heterodoxus spiniger: Found mostly in tropical regions; rarely seen on

dogs in North America but observed on wild canids like coyotes and

foxes.

2. Sucking Lice

 -Feed on blood and have sharp, pointed mouthparts.

 -The species affecting dogs is Linognathus setosus.

 -Common in tropical and subtropical regions across North and South America, Africa, India, and Asia.

Signs Your Dog Has Lice

Adult lice are visible to the naked eye and are about the size of a sesame seed (2-4

millimeters). They range in color from yellow to tan or medium brown. You can spot them

by parting your dog’s hair and examining the hair shafts. Unlike fleas, which appear dark

and almost black, lice are lighter in color.

Chewing lice tend to move around more than sucking lice, which embed their mouthparts

into the skin like ticks. To confirm an infestation, use a flea comb to inspect your dog’s

coat.

Dog owners often mistake lice eggs (nits) for dandruff. To differentiate, shake the hair

removed from your dog: dandruff flakes will fall off, while lice eggs will cling stubbornly to

the hair.

Additional signs of lice infestations include:

 -Intense scratching and itching.

 -A rough, dry, or matted coat.

 -Hair loss, especially around the ears, neck, shoulders, groin, and rectal areas.

 -Small wounds or bacterial infections caused by sucking lice bites.

 -Restlessness or discomfort.

 -Anemia in severe cases, particularly in small dogs or puppies.

 -Secondary infections such as tapeworms or other parasites spread by lice.

How Do Dogs Get Lice?

Lice have limited mobility; they cannot jump, hop, or fly. They crawl and usually spread

through direct contact with an infested animal. Contaminated bedding, collars, or

grooming tools can also transmit lice. Dogs in communal settings like daycare centers,

kennels, or parks are at higher risk.

The louse life cycle consists of three stages: egg, nymph, and adult.

 -Female lice lay tiny yellow or white eggs at the base of hair shafts, gluing them

firmly in place.

 -Eggs hatch into immature lice (nymphs) within a week.

 -Nymphs mature into adults in about another week, completing the cycle in 3-4

weeks.

How to Treat Dog Lice

Lice infestations are rare among well-cared-for dogs due to the widespread use of monthly

flea and tick preventives. However, they are more common in stray, feral, or neglected

animals.

For severe infestations:

 -Clip matted hair where lice and eggs are attached.

- Use a flea comb to remove live and dead lice from the rest of the coat. Afterward,

immerse the comb in water mixed with flea shampoo or insecticide for at least 10

minutes.

Topical insecticides, including permethrin, are effective against lice. Always consult your

veterinarian to choose the safest treatment for your dog, considering their age, breed, and

health. Be cautious if you own cats, as some dog treatments can be toxic to felines.