Healthy Pet Series: Vancouver Vets about Skin Diseases in Dogs

Skin disease is one of the most common reasons for which dog owners visit our Vancouver Animal Hospital. On average more than 20 per cent of all veterinary cases are dermatological and the majority of the patients are dogs.

Skin diseases are challenging yet frustrating for both dog owners and our Vancouver vets. The clinical manifestations of many different skin problems are very similar and may require a wide range of laboratory tests and trail therapy in order to reach a diagnosis. In some cases this may take several months. On rare occasions the underlying cause of an animal’s skin problems is never discovered and life-long symptomatic therapy is required. Dermatological therapy depends heavily on medicated shampoos and treatments applied directly to the skin itself and consequently involves considerable investment of time and effort by the owners of affected dogs.

Fleas are probably the most common cause of skin disease in dogs. The usual species of flea found on dogs is the ear flea. The life cycle of the flea varies between three weeks and two years depending on climatic conditions. The greater part of the life cycle (about 90 percent) is spent off the host animal in the environment, with adult fleas jumping on to the host to obtain a blood meal. They may also feed on humans. Typically skin disease is seasonal, coinciding with a peak in flea activity in late summer and early autumn, although with the widespread use of central heating it has become an all-year round problem. It is likely that skin disease occurs as a result of an allergic reaction to flea saliva injected when the flea feeds, which leads to a sensation of itchiness (pruritus) and causes the dog to scratch and chew.

The degree of pruritus varies. Some dogs may tolerate large numbers of fleas on the skin with few clinical signs whilst others may be extremely itchy (pruritic) for many days after just a single flea bite. Affected dogs may be generally itchy, but often are particularly so at the base of the tail in the posterior portion of the back. In multi-pet households cats are often symptomless carriers of fleas and introduce them into the house. Vancouver vets at our Vancouver Animal Hospital clinic often initially recommends a strict flea eradication programme when confronted with an itchy dog in order to rule out this diagnosis at an early stage, even if no fleas have actually been seen.