Cat Flea vs Dog Flea

Fleas can make a dog’s life miserable. If he has an infestation, it can make the owner’s life very difficult, too!

Fleas are parasites that feed on the blood of animals including cats, dogs, and humans. Cat fleas and dog fleas are different. While dog fleas can only feed on dogs, cat fleas can feed on either cats or dogs. In fact, most dogs in the United States suffering from fleas have cat fleas.

The Cat Fleas

Cat fleas (Ctenocephalides felis) are a different species from dog fleas but they can only be distinguished by observing them with a microscope. The fleas are brown and their eggs are white. The body of this flea is about 0.5 millimeters with a gently curved head. It has combs on the head around the mouth, called genal combs, and behind the head (pronotal combs). These allow it to anchor securely to an animal so that it can feed. The compressed body lets it move quickly on an animal.

Cats like to eat fleas, so you may not recognize a flea problem with them as easily as you would with a dog. That doesn’t mean they have no fleas! You may see fleas on your cat or you may just notice your cat nibbling and licking himself. Cats are well known for grooming themselves, so they may remove the fleas well enough that you don’t notice them.

However, cat flea populations grow extremely quickly. The adult female lays as many as 20 eggs a day, and fleas live for up to one year if they have enough blood to feed on. They nest on the host animal in its usual resting place.

Cat fleas don’t cause dermatitis as severe as dog fleas but can transmit dangerous diseases.

The Dog Fleas

The dog fleas (Ctenocephalides canis) are very rare in North America but have spread in Europe. The fleas are reddish brown with a sharply curved head. They are larger than cat fleas. They have stiff hair-like structures on their back legs. Their bodies are about 2 millimeters long but can grow up to 5 millimeters. They can cause severe dermatitis in animals.

Female dog fleas can produce 4000 eggs during their life. They jump from one host animal to another and can also infest yards and gardens.

Dog fleas can cause worms in dogs. If a flea is infected and the dog picks the flea off and swallows it, he may become infected and develop worms.

Adult fleas usually represent only five percent of the flea population. This makes eliminating them difficult because you have to kill not only the fleas but the eggs too.

During the process of evolution, fleas lost their wings but developed very strong hind legs that allow it to jump as much as 200 times their body length. This lets them easily jump from the animal to another surface.

Fleas can and will bite humans but do not cause an infestation.


There are many reasons that fleas cause a problem. They can carry disease. They definitely irritate the host animal causing itching and discomfort. They can also infest yards or homes. In homes, they generally nest in dog or cat beds and in carpets.

Good pet grooming is imperative. Natural or chemical remedies are often needed too. It is best to prevent fleas since they are very hard to get rid of.

So, inspect your pet today. Look for fleas or eggs on the animal. Even if you do not see any, groom the pet well and look for scratching, licking, and nibbling. If you see this activity, start immediately to remedy the situation!