What are Ticks?
Ticks are tiny parasites that feed on the blood of their hosts. They are closely related to mites, spiders and scorpions. There are soft (argasid) ticks and hard (ixodid) ticks. Hard ticks are more common, reproduce faster and tend to cause more problems for domestic dogs. Ticks are attracted to animals by warmth, physical contact and odors. They can carry and transmit bacterial organisms that cause infectious diseases - such as Borrelia burgdorferi, which are the bacteria that cause Lyme disease. Tick bites cause irritation to the skin around the area of the bite, itchiness, head-shaking (if the tick is on the face or in the ears) and sometimes even paralysis. They also can cause a dog to suffer fever, appetite loss, pain, lethargy and depression. Some ticks carry infectious organisms that can infect people, so owners should be vigilant when they remove ticks from their dogs.
Specific Ticks That Bother Dogs
The hard (ixotid) ticks that affect domestic dogs include:
- Black-legged tick (Ixodes scapularis): The black-legged tick primarily inhabits the northeastern, southeastern and midwestern United States, although it can also be found on the Pacific coast. Ixodes scapularis is responsible for borreliosis, also called Lyme disease, as it is a vector (carrier) of Borrelia burgdorferi. Lyme disease in dogs causes arthritis, fever and sometimes neurological signs.
- American dog tick (Dermacentor variabilis): The American dog tick is found throughout North America. It is especially prevalent along the Atlantic coast, in areas of thick shrubs and long beach grass. Dermacentor variabilis is responsible for Rocky Mountain spotted fever and tick paralysis in dogs, because it is a carrier (vector) of Rhipicephalus ricketsii. Rocky Mountain spotted fever causes affected dogs to suffer from inflammation and death of the tissues of blood vessels (necrotizing vasculitis).
- Brown dog tick (Rhipicephalus sanguineus): The brown dog tick is also widely distributed throughout North America. It is a carrier of Ehrlicia canis and is associated with babesiosis, ehrlichiosis and tick paralysis in companion dogs.
The soft (argasid) ticks that affect domestic dogs include:
- The main soft (argasid) tick that affects dogs in the United States is the spinous ear tick (Otobius megnini). It is also common in South Africa, India and South America. The soft spinous ear tick causes irritation, head-shaking and overall ill-thrift.
References: Ticks & Dogs