-
Characteristics of arachnid larval stages
- 3 pairs of legs
- Nymphs and adults have 4 pairs of legs
- Head, thorax, abdomen are fused
- Antennae and mandibles not present
- Mouth parts are covered by a false head (capitulum)
-
This order includes ticks and mites
Order Acarina
-
This class includes spiders and scorpions
Class Arachnida
-
Non reproductive adults AKA
Nymphs
-
Sub order of ticks
Metastigmata
-
2 families of ticks
- Family Ixodidae (hard ticks) (have scutum)
- Family Argasidae (soft ticks) (no scutum)
-
Interstadially AKA
Transtadial
-
Ixodid tick characteristics
- Shield/scutum covers entire dorsal surface
- Capitulum (head) projects anteriorly
-
How many times does a Ixodid tick molt?
Twice
-
Which 2 ticks can transmit transtadial?
- Two host tick
- Three host tick
-
Ixodid one host tick
- Completes both molts without leaving the host
- EX: Boophilus annulates
-
Ixodid two host tick
Seed tick larvae will molt to nymph, nymph drops off the 1st host, molts to adult, then adult locates the 2nd host
-
Ixodid three host tick
Larvae drops off host to molt to nymph, nymph finds 2nd host, nymph drops off 2nd host to molt to adult, adult locates a 3rd host
-
Ixodid one host tick transmits how?
Transovarial
-
Transtadial transmission
Infection is acquired by a larval tick and carried through the molt to the nymph stage and then conveyed to the host, or infection acquired by a nymph who is carried through the molt to adult and conveyed to the host
-
Ixodid 3 host tick examples
- Dermacentor variabilis
- Rhipicephalus sanquinius
-
4 stages of a tick life cycle
- Egg
- Six legged larvae "seed tick"
- Eight legged larvae "nymph"
- Eight legged larvae "mature adult" (sexually mature)
Complete cycle can take up to 3 years
-
Historical importance of Texas Cattle Fever
Proved transmission of a disease by an intermediate host
-
Texas cattle fever
- Vector: Boophilus annulates
- One host tick
- Transovarial transmission
- Transmits Babesia bovis and Babesia bigemina
- 1893
- Kilbourne (vet) and Smith (MD, taught at Baylor)
-
Tick borne diseases
- Piroplasmosis/Babesiosis
- Rocky mountain spotted fever
- Coxiella
- Cowdria "Hearwater"
- Ehrlichia
-
Piroplasmosis other names
- Babesiosis
- Texas Fever
- Red Water
-
Piroplasmosis is a ___ disease
Protozoan of the order Sporozoa
-
Piroplasmosis facts
- Genus: Babesia
- Utilize RBC to parasitize and multiply by binary fission
- Lyse the RBC
- Symptoms: Anemia
-
Intermediate host of Piroplasmosis/Babesia
Boophilus annulates
-
Transmission route of Piroplasmosis/Babesia
Transovarial
-
Etiology of Canine Piroplasmosis/Babesiosis
- Babesia canis
- Babesia gibsoni (Australia/Europe)
-
Intermediate host of Canine Piroplasmosis/Baebsiosis
Rhipicephalus sanquinius
-
3 types of Piroplasmosis/Babesiosis
- Bovine Babesiosis
- Equine Babesiosis
- Canine Babesiosis
-
Rocky mountain spotted fever facts
- Rickettsia borne disease
- Etiology: Rickettsia rickettsii
- Intermediate host: Dermacentor andersoni
- Dermacentor variablis
-
Wood tick
Dermacentor andersoni
-
Coxiella facts
- Rickettsia borne disease
- Etiology: Coxiella burnetti
- "Q fever"
- Australia 1937
- Intermediate host: Dermacentor andersoni
- Dermacentor occidentalis
- Rhipicephalus sanquineus
- Otobius megnini (spider tick)
-
Equine Piroplasmosis/Babesiosis facts
- Etiology: Babesia caballi –horses, mules, and donkeys
- Babesia equi –all the above plus zebras Intermediate Host: Boophilus annulatus
-
Spider tick
Otobius megnini
-
Cowdria facts:
- Rickettsia borne disease
- Etiology: Cowdria ruminatium
- Disease Name: Hearwater
- Characteristic Lesion: Hydropericardium
- Intermediate Host: Amblyomma
-
Ehrlichia facts:
- Rickettsia borne disease
- Etiology: Ehrlichia canis
- In WBC & RBC
- Disease: Vietnam Disease
- Intermediate Host: Rhipicephalus sanquinius
-
Lone star tick
Amblyomma americanum
-
Gulf coast tick
Amblyomma maculatum
-
Idexx Tests
- Snap # DX test: HW, lyme disease, and erlichia species
- Snap 4DX test: HW, lyme disease, erlichia species and anaplasma species
-
Tick that transmits lyme disease
Ixodes dammini (Ixodes scapularis)
-
Brown dog tick
Ripicephlaus sanquinius
-
-
Mites sub order names
- Mesostigmata
- Astigmata
- Prostigmata
-
Respiratory pore in middle of mite body
Stigma
-
How many species of mites?
30000
-
How many species of mites cause health problems
250
-
Mite in ear of cattle
Raillietia auris
-
Mite that causes yellowish nodules in the lungs of monkeys?
Pneumonyssus simicola
-
Mite in the nasal passage of dogs
Pneumonyssus caninum
-
Mite found in birds nest and chicken houses that can feed on man
Dermanyssus gallinae
-
Mite found in rodents, snakes, and birds. Remain on the host and is zoonotic
Ornithonyssus species
-
Most common mite to infect dogs and cats?
Otodectes cynotis (ear mite)
-
Sub order Astigmata includes what species?
Mange mites AKA Clasping hair mites
-
Families Psoroptidae and Sacoptidae cause what?
Scabies, signs include pruritis, alopecia, epidermal hyperpigmentation and epidermal hyperplasia
-
2 ways to identify mange mites
- Host and distribution of lesions
- Jointed (Psoroptidae) or unjointed legs (Sarcoptidae)
-
Sarcoptic mange starts where on a dog?
Margins of the ears
-
Sarcoptic mange etiology in dog
Sarcoptes scabei
-
Sarcoptic mange etiology in cats
Notoedres cati
-
Sarcoptic mange starts where on a cat?
Ears, then face and paws
-
With scraping for sarcoptic mange how must you do it?
Deep skin scrapings
-
Family Psoroptidae
- Psoroptes- sheep, cattle, rabbits and horse (starts at withers and generalizes)
- Chorioptes- horse (starts at pasterns and moves up leg)
- Otodectes- dogs, cats, pocket pets (starts at ear canal and moves to face)
-
Otodectes cynotis
- Psoroptic mite
- In dogs and cats
- Most common mange mite
- Live on surface of the skin
-
Treatment for Otodectes cynotis
Acarexx (0.01% Ivermectin)
-
Taxonomy for Demodex
- Suborder: Prostigmata
- Super family: Cheyletoidea
- Family: Demodicidae
-
Demodex lives where?
On skin and glandular ducts
-
Demodex species in dog
Demodex canis
-
2 forms of demodectic mange
- Localized demodicosis
- Generalized demodicosis
-
2 classes of demodex based on age
- Juvenile onset (3-12 months old)
- Adult onset (2-4 years old)
-
What percentage of generalized demodicosis dogs will recover without treatment?
30-50%
-
Nickname for demodicosis?
Red mange due to the concurrent staph infection
-
Where do lesions of demodicosis start?
On the face
-
Drug contraindication with demodicosis?
Corticosteroids
-
2 causes of demodex
- Mites
- Suppressed immune system
-
Drug of choice for demodicosis?
Amitraz
-
Treatments for demodicosis
- Amitraz
- Milbemycin oxime (Interceptor) (Novartis)
- Ivermectin (Ivomec) (Merial)
- Moxidectin and Imdiacloprid (Advantage multi)
- Lufenuron (Program) (Novartis)
-
Treatment regimen for Amitraz (demodex)
- 1 dip every 2 weeks for 5 treatments or at least twice after multiple skin scrapings come back negative
- 85% success
-
Treatment regimen for Interceptor (demodex)
- Monthly dose given twice a day every 30 days for 3 months
- 96% remission in 3 months
- 29% relapse in 1 year
-
Treatment regimen for Ivermectin (demodex)
- 0.6 mg/kg/day
- Can cause ataxia, coma and death
-
Treatment regimen for Advantage multi (demodex)
- Oral: 1 cc/60 lbs/day until 2 negative scrapes
- Topical: Once a week for 4 weeks
-
Failures of treatment for Demodex
- Premature suspension of treatment
- Failure to treat skin bacterial infection
- Stress within environment
- Heat cycle
- Iatrogenically induced with glucocorticoids
- Underlying concurrent disease
- Idiopathic problems
-
Demodex treatment by doctor at Cornell University
- Dr. Danny Scott
- "Scotts solution"
- 5 parts propylene glycol (antibiotic) with 1 part Ectoral (organophosphate) and applied to 1/3 of body everyday
-
Demodex species in cow
Demodex bovis
-
Demodex species in sheep
Demodex ovis
-
Demodex species in goats
Demodex caprae
-
Demodex species in pigs
Demodex phyllodides
-
Demodex species in horse
Demodex equi
-
Demodex species in cats
- Demodex cati
- Demodex gatoi
-
Family Cheyletiellidae nickname
Big claw mites
-
Walking dandruff mite in dogs
Cheyletiella yasguri
-
Cheyletiellidae mite in cats
Cheyletiella blakei
-
Cheyletiellidae mite in rabbits
Cheyletiella parasitivorax
-
Sheep itch mite
- Psorobis ovis
- Reportable disease
-
Family Trombiculidae nickname
Chiggers
-
What stage of chiggers effects man?
Larval
-
Disease caused by triggers
Trombiculiasis
|
|