TICK INFORMATION
By Kind Permission Of
Larisa Vredevoe, Ph.D, Department of Entomology, University of California, Davis
Family Argasidae (Soft Ticks)
Ornithodorus coriaceus (the Pajahuello tick [paja = straw
colored, huello = treading])
Associated with coastal and sierra foothill habitats from San Diego to Humboldt county.
Found in and around resting places of their large mammalian hosts (primarily deer and
cattle). However, this tick will readily take blood from almost any warm blooded mammal in
the laboratory (Furman and Loomis 1984). Humans may accidentally encounter this tick when
they come in contact with host bedding sites, especially during activities such as hunting
and camping. For humans, the bite of this tick is notoriously painful, resulting in a
localized inflammatory response due to a toxic substance introduced into the bite site
during feeding .
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Various Stages of the Pajahuello Tick |
Human Reaction to Pajahuello Tick Bite |
Otobius megnini (the spinose ear tick)
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The Spinose Ear Tick |
An important pest of livestock and horses throughout the western United
States. In California, this tick is frequently found in the warm, dry regions of the
central valley down to the southern portion of the state. Rarely, these ticks have been
found on humans, dogs, cats, and sheep. Heavy infestations with this tick can result in
intense irritation, rubbing, and hair loss in livestock (Furman and Loomis 1984).
Argas sanchezi and Argas persicus (poultry ticks)
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A Poultry Tick |
These ticks are common pests of chickens and turkeys, but generally do not cause serious problems except for small flocks on farms which provide wooden housing that encourages tick establishment. Eggs are laid in crevices in the wood. All stages of these ticks remain around the roosting area of poultry, hiding in crevices during the day and generally feeding at night. Ticks can survive in empty poultry housing for years. Argas sanchezi is a common tick of chickens, turkeys, and wild birds in California and other western states. In California it is primarily found in central valley dry climates from Shasta down to Kern county, as well as the dry coastal and inland southern California regions. Argas persicus infests chickens mostly in the eastern U.S., and only rarely has been collected in California in Nevada county (Furman and Loomis 1984).
Dermacentor albipictus (the winter tick)
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Partially Fed Adult Winter Tick Removed From a Horse |
This one host tick is found throughout North America. It is widely
distributed throughout California, but populations are concentrated around the central
coastal and sierra foothill areas. It primarily feeds on horses and deer from fall through
early spring. Heavy infestations of horses may cause emaciation and anemia (Furman and
Loomis 1984). After hatching from the egg, larvae attach to a host, feed and detach,
remaining on the animal. Subsequently, they molt to the nymphal stage, resume feeding and
detach again. After they develop into adults and feed once again, they drop to the ground
and lay their eggs, where the cycle begins once again.
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Adult Pacific Coast Tick |
The Pacific Coast Tick is a three host tick which commonly feeds on rodents, especially squirrels, as subadults, and on cattle, horses, deer, and humans as adults. This is one of the most widely distributed ticks in California. It is found throughout the state except for the very dry regions of the central valley and the southeastern desert region.The only other areas it has been collected in are Oregon and Baja, Mexico (Furman and Loomis 1984).
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Adult Rocky Mountain Wood Tick |
The Rocky Mountain wood tick is a three host tick which as a subadult primarily feeds on small rodents; as adults they focus on large mammals, especially deer, humans, canids, and livestock. This tick is well known as a vector of the Rocky Mountain spotted fever rickettsia in the northwestern U.S. and Canada, the Colorado tick fever virus, and the bacteria which causes tularemia (hunter's disease). It is also commonly responsible for tick paralysis in humans, livestock, and wild mammals (Furman and Loomis 1984). However, in California, this tick poses little threat to human and animal health because of its scanty distribution in less populated areas of the state. It has been collected primarily in the upper eastern part of the state, from Modoc county down to the eastern range of the northern Sierras.
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Adult American Dog Tick |
The American dog tick is a three host tick that feeds on rodents and lagomorphs during its subadult life stages, and large mammals, frequently canids and humans, as adults. It is the most important vector of the Rocky Mountain spotted fever rickettsia in the eastern U.S. and is also able to transmit the bacteria which causes tularemia (hunter's disease). It has also been found responsible for tick paralysis in some.
PAMPERED PUPS FLEA AND TICK TREATMENT