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Two types of mites
- Sarcoptiform
- Nonsaroptiform
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Two types of ticks
- Argasid (Soft)
- Ixodid (Hard)
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Four developmental stages of mites and ticks
- egg
- larva - six legged
- nymph - eight-legged
- adult - eight-legged
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Acariasis
infestation with mites or ticks
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Sarcoptidae
- A family or mites
- Mites that burrow or tunnel within the epidermis, causing pruitus
- spread by direct contact
- REPORTABLE IN CATTLE
- disease called SCABIES
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Psoroptidae
- a family of mites
- mites that reside ont he surface of the skin or ear canals
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Genera in Sarcoptidae
- Sarcoptes
- Notoedres
- Cnemidocoptes
- Trixacarus
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Physical description of Sarcoptidae
- very tiny
- round in shape
- legs have "stalks" (pedicels) with long suckers
- legs can be short or long, straight or jointed
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- Sarcoptes scabei variety canis
- Canine scabies mite
- long, unjointed pedicel
- suckers on some of the pedicels
- terminal anal opening
- zoonotic potential
- presents as "crusts" on body
- zoonotic
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- Notoedres cati
- Felin scabies mite
- smaller than Sarcoptes spps.
- dorsal subterminal anal opening
- host specific, can be seen on rabbits
- zoonotic
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- Demodex sp.
- commensal
- burrowing - lives in hair follicles
- host specific
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Demodex canis pathogenesis
- normal commensal causes disease when predisposition present.
- usually kept in check by healthy body but causes secondary problems.
- may be generalized or local
- alopecia with no or mild puritis.
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Family Psoroptidae
- live on surface of skin
- long, jointed pedicels
- (P)Soroptes have Segments
- multiple species - Psoroptes ovis, bovis, equi, cuniculi
- Large animal Psoroptes sp. REPORTABLE to USDA except P. cuniculi
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Psoroptes spp. lifecycle
- confined to skin surface
- eat by siphoning serous exudate
- adutls lay over 100 eggs
- life cycle complete in 10 days
- live for 1 month
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- Psoroptes cuniculi
- ear canker mite of ribbits
- may also infest goats, horse -- less severe
- direct contact
- long jointed pedicels with suckers
- mites live in ceruminous discharge
- "corn flake" appearance of ears
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- Chorioptic Mange
- less pathogenic, usually subclinical
- superficial, mildly puritic, flaky dermatitis around tail and hind legs
- usually self limiting in mobile cattle
- causes "scalding" of legs and scrotum on rams and sheep
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- Psoroptidae
- Otodectes cynotis
- ear ites, short, unjointed pedicels with suckers
- external ear canal of dogs, cats and ferrets
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3 Genus within Family Psoroptidae
- Psoroptes
- Chorioptes
- Otodectes
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- Family Psoroptidae
- Otodectes cynotis
- can cause otitis externa
- extremely puritic
- spread by direct contact, extremely contagious
- classic "coffee ground" apperance of otic debris
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- Family Cheyletiellidae
- Cheyletiella parasitivorax
- Walking dandruff
- live on the skin surface of cats, rabbits, dogs
- hook-like mouthparts and comb structures on legs
- bell pepper shaped body, doesn't burrow
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- Family Cheyletiellidae
- Cheyletiella parasitivorax
- diagnosed by visualizing moving dandruff along dorsal midline
- find with flea comb or clear cellophane tape
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- Chorioptes spp
- surface mites of ruminants and horses
- most strains = C. bovis
- look very similar to Psoroptes
- short, unjointed pedicels with suckers
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How to differentiate mites
- Sacroptes and Notoedres - long, unsegmetned pedicels
- Psoroptes - long, segmented pedicels
- Otodectes - short, unsegmented pedicels
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Family Ixodidae
Hard ticks
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Questing
crawl to the tips of plants with front legs extended in order to reach a potential host
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- Ixodes scapularis
- Deer Tick
- adults on horses, dogs, deer and humans
- eastern united states
- Vector for: tularemia, Babesia sp., Borrelia burgdorferi (Lyme disease)
- tick paralysis
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- Ixodes pacificus
- Western black-legged tick
- only tick in california that transmits Lyme disease
- more common in the humid northwestern coastal area and western slope of the northern Sierra Nevada mountains
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- Amblyomma americanum
- Lone star tick
- 3 host tick
- wide rangs of mammal hosts, humans
- longer mouthparts
- warmer climates - south, midwest, east coast of US
- Vector for tularemia, RMSF and can cause tick paralysis
- White spot on scutum
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- Ambylomma maculatum
- Gulf Coast Tick
- 3 host tick
- adults on cattle, sheep, dogs, humans
- east coast and gulf coast of US
- tick paralysis
- Ornate scutum - silvery markings
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- Rhipicephalus sanguinous
- Brown dog tick
- dogs, sometimes humans
- throughout NA
- Vector for Babesia canis, Anaplasma sp., Ehrlichia sp., Borrelia sp., Mycoplasma sp., and tick paralysis in humans
- Lateral projections on side of head
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- Rhipicephalus annulatus
- Texas Cattle Fever or North American Tick
- formerly Boophilus annulatus
- 1 host- cattle
- Eradicated in US
- REPORTABLE TO USDA
- Vector for Babesia bigemina -- bovine piroplasmosis
- 40-100mil spent on keeping tick at bay
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- Dermacentor variabilis
- American Dog Tick or Wood Tick
- 3 hosts
- small mammals, dogs, humans
- throughout the US
- vector for RMSF, tularemia, causes tick paralysis
- ornate scutum
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- Dermacentor andersoni
- Rocky Mountain Wood Tick
- adults on dogs, horses, cattle, goats, sheep and humans
- rocky mountains manly
- Vector for Rocky mountain spotted fever, tularemia, colorado tick fever, Q-fever and tick paralysis
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Soft ticks
- Argas spp.
- mostly attacks birds, but will attack humans
- no scutum
- mouthparts not seen from above
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- Argas persicus
- foul or poultry tick
- production losses
- flaccid paralysis of young chickens
- all life stages can be collected from bird or its envrionment
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- Otobius megnini
- Spinose ear tick
- only larval and nymph stages are parasitic
- adult stages are free living
- larvae and nymphs can feed on horses, cattle, sheep, goats, dogs
- Southwestern USA
- occur in large numbers, invade the external ear canal
- cause pruitus, ulceration of ears
- visualized with otoscope
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