Dog louse
The dog louse is a parasitic insect that specifically infests dogs, feeding on their blood, skin secretions, and flakes. It belongs to the genus Trichodectes and is one of approximately 5,000 species of lice globally. Unlike sucking lice, which feed by drawing blood, dog lice are classified as chewing lice, utilizing their sharp jaws to bite into the dog's skin. These tiny, flat insects are characterized by their light-colored bodies and wide, oval abdomens, equipped with six short legs for gripping fur.
Dog lice can cause significant discomfort for their hosts, leading to skin irritations, itching, and even diseases. Stressed dogs may experience weight loss and, in severe cases, anemia due to blood loss. Additionally, dog lice can transmit tapeworms to their hosts, further complicating health issues. While they can survive for a few days without feeding, they remain permanently attached to their dog host throughout their lifecycle. Infestations are particularly concerning for puppies, which are more vulnerable due to their smaller blood volumes. Overall, understanding the biology and effects of dog lice can help in managing and preventing infestations in canine companions.
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Dog louse
The dog louse is a parasite, or a creature which lives on another creature. This insect species infects dogs and feeds on their blood, skin secretions, and skin flakes.
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Psocodea
Family: Trichodectidae
Genus: Trichodectes
Species: Canis
Among the animals which infect dogs and cause discomfort or illness is the dog louse. This tiny insect is only a few millimeters long, but it makes up for its small size by causing skin irritations, itching, and disease in dogs. The dog louse is one of almost 5,000 species of lice worldwide, each a parasite on people or a particular species of animal. Parasites may be plants or animals which live inside or on the outside of other plants and animals, called hosts. Parasites take their food from the hosts.
All lice have either sucking or chewing mouthparts. The dog louse and 2,650 other species are called chewing lice, while the other lice, including those which attack people, are called sucking lice. These distinctions are based on the type of mouthparts the lice have, since both kinds of lice feed on skin flakes, blood, and other bodily liquids. The dog louse has sharp, pointed jaws for biting into the dog's skin. The dog louse's diet consists of dog's blood, secretions, and flakes from the dog's skin.
The dog louse's body is light colored, possibly white or yellow. It is a small, flat insect with a wide, oval abdomen, or lower body section. The abdomen has ring-like segments. Many, tiny hairs cover the abdomen and help detect the surroundings. In front of the abdomen is the middle section of the body, called the thorax. The thorax has six, short, fat legs. Each leg has one large claw for gripping tightly the hairs of the dog. Unlike many other insect species, the louse does not have wings on its thorax. Ahead of the thorax is the small, narrow head with two short antennae and the mouthparts.
A dog louse may survive up to two or three days between meals, but it is also possible for it to die within 12 hours of not eating, depending on conditions. A louse does not leave its host unless the dog dies. Since it cannot jump or fly, it must wait for another dog to come in contact with its host if it is going to move to another dog.
The female dog louse lays her eggs, called nits, in clumps among the dog's hairs and attaches them securely with fast-drying cement from her body. After several days the nits hatch. The young hatch by making small holes in the tops of their shells and breathing in air. As their bodies release the air into the other ends of the shells, pressure builds behind their bodies and forces the young out the tops. They mature after several more days and may live up to a few months. A dog louse can live on its host for its entire lifecycle, making it a permanent parasite.
When the dog louse bites the dog, the wounds itch and cause redness and soreness in the skin. If the discomfort is great enough from a large number of dog lice, the dog may stop eating and lose weight. The dog louse may also cause another disease in the dog called tapeworm. Tapeworm (Dipylidium caninum) is a parasitic worm which infects the louse and then infects the dog when the louse bites the dog. The tapeworm parasite lives inside the dog's intestine and feeds on the dog's food. Puppies are most likely to have more negative side effects from dog louse infestations since they have smaller volumes of blood. In some severe infestation cases, the host can lose up to one-fourth of its blood, causing anemia.
Bibliography
Croft, August. “Dog Lice vs Fleas: What’s the Difference?” A-Z Animals, 30 Oct. 2023, a-z-animals.com/blog/dog-lice-vs-fleas/. Accessed 29 Apr. 2024.
Hinsperger, Brad. “Lice in Dogs: Symptoms, Treatment and Prevention.” Kingsdale Animal Hospital, 26 Apr. 2024, www.kingsdale.com/lice-in-dogs-symptoms-treatment-and-prevention#:~:text=Lice%20in%20dogs%20or%20pediculosis,they%20appear%20as%20white%20flakes. Accessed 29 Apr. 2024.
Lundgren, Becky. “Lice in Dogs and Cats.” Veterinary Information Network, 15 May. 2023, veterinarypartner.vin.com/default.aspx?pid=19239&id=4952773. Accessed 29 Apr. 2024.