Lice are small, flightless insects that live in the hair or feathers of animals and people. There are 2 basic types of lice. Biting or chewing lice (order Mallophaga) infest both birds and mammals. They feed mostly on skin debris and the secretions of their hosts. Blood-sucking lice (order Anoplura) are skin parasites of mammals only. Typically, lice are species specific; that is, they do not readily transfer from one animal species to another.
Pruritus is defined as an unpleasant sensation within the skin that provokes the desire to scratch. Itching is a sign, not a diagnosis or specific disease. The most common causes of itching are parasites, infections, and allergies. There are many skin diseases that do not initially cause itching. Itching may develop because of secondary bacterial or yeast infections. It is possible that by the time itching develops the initial cause is long gone.
Hyperpigmentation is a darkening and thickening of the skin seen in dogs. It is not a specific disease but a reaction of a dog’s body to certain conditions.
Hyperpigmentation appears as light-brown-to-black, velvety, rough areas of thickened, often hairless skin. The usual sites are in the legs and groin area. It can be primary or secondary. Primary diseases that cause hyperpigmentation can occur in any breed but especially Dachshunds. Signs are
A hygroma is a fluid-filled sac that develops over bony prominences and pressure points, especially in large breeds of dogs. Repeated trauma from lying on hard surfaces leads to inflammation. This results in a dense-walled, fluid-filled cavity. A soft, flexible, fluid-filled, painless swelling develops over pressure points, especially the elbow. If long lasting, severe inflammation may develop, with ulcers, infection, abscesses, granulomas (masses of inf
Hives or skin rashes (urticaria) are localized patches of red, swollen, usually itchy, skin. They often develop and disappear suddenly. Hives are relatively uncommon in dogs. The most frequent causes are insect bites or stings, shampoos, and medications. Other causes include contact with toxic plants or chemicals. Friction, sunlight, heat, exercise, stress, and genetic abnormalities may cause or intensify the rash. Hives may develop after inhaling or consuming allerg
Alopecia is the partial or complete lack of hairs in areas where they are normally present. Hair loss is a sign and its underlying cause must be determined for the condition to be successfully treated. If a dog has hair loss and is also scratching the area excessively, the itching should be investigated first.
There are many causes of hair loss, which can be congenital (the animal is born with the condition)
Flies are winged insects that are usually just an annoyance, but they can transmit disease and cause problems in animals. They belong to a large, complex order of insects called Diptera. Flies vary greatly in size, food preference, development, and habits. As adults, flies may feed on blood, saliva, tears, or mucus. They also spread bacteria, viruses, and parasites. The order Diptera includes not only the common house fly and many other insects we commonly call flies
Fleas are small wingless insects that feed on animal blood. In addition to being a nuisance, they can also transmit diseases and cause allergies or anemia. There are more than 2,200 species of fleas recognized worldwide. In North America, only a few species commonly infest house pets. Two common species of flea are the cat flea (Ctenocephalides felis) and the dog flea (Ctenocephalides canis). However,
Eosinophilic granuloma complex is rare in dogs. It is recognized more commonly in cats and horses. When seen in the dog, this disorder is associated with unusual reactions to insect bites or other hypersensitivity reactions. They will often appear as bumps or nodules, in the mouth, on the lips, or anywhere on the body. Over time, these may become ulcerated or crusted. Any breed may be affected, but Siberian Huskies and Cavalier King Charles Spaniels may be at greater
This disease is seen worldwide but is more common in the tropics. It is known by a number of names, including “strawberry footrot.” Among companion animals, it is seen most frequently in horses. Dogs and cats rarely have this disease. The few reported human cases have usually been associated with handling diseased animals.
The disease is caused by Dermatophilus congolensis bacteria. It is possible that the bacteri