Arachnids Flashcards
Describe arachnids.
-nymphs & adults = 4 pairs of legs
-larvae = 3 pairs of legs
-body = cephalo-thorax & abdomen
-no antennae
-PAMPs
Describe Family Ixodidae.
‘Hard ticks’
Time for LC to be complete depends on:
>species of tick
>environment
>availability of suitable hosts
Damaging effects to host:
>blood taken
>lesions from mouthparts predispose for other infections
>transmission of disease
>tick paralysis (reversal if removed)
Describe Ixodes spp.
‘Black legged tick/deer tick’
-host: all mammals, birds, humans zoonotic
>larvae & nymphs of some species feed on mice & adults on deer
-ID: 4mm, dark brown, no festoons, long palps, inornate scutum anal groove arch anterior to anus
-LC: 3 host tick
>requires adult females to engorge in fall, overwinter, & lay egg in spring (when adult females dont find suitable host LC takes longer up to 4 yr)
-SOI: skin (all over body) esp axilla, inguinal region, face & ears
-CS:
>paralysis in animals
>local skin reaction to bite
>transmit Lyme disease (Borrelia burgdorferi)
>granulocytic anaplasmosis
>human babesiosis (B. Microti)
-diagnosis: engorged females seen
Describe Dermacentor spp.
*Dermacentor variabilis: ‘American dog tick’
*D. Andersoni: ‘Rocky Mountain wood tick’
-hosts: (most common tick on dogs in NA)
>larvae & nymphs feed on sm rodents
>adults feed on dogs, lg host, human zoonotic
-ID: unfed 6mm/fed 15mm, rectangular basis capituli, short palps, ornate scutum, festoons
-LC: 3 host tick (complete LC take months-yr)
-SOI: skin around head/neck
-CS: transmit rock mountain spotted fever (RMSF), cytauxzoonosis, tularemia, tick paralysis
-diagnosis: ID of tick
Describe Rhipicephalus sanguineus.
‘Brown dog tick’
-host: (worldwide - most common in southern US)
>dogs & humans zoonotic
ID: hexagonal basis capituli, 5mm unfed/13mm fed, inornate scutum, short palps, festoons
-LC: 3 host tick (well adapted to indoor living)
-SOI: skin
>adults prefer between toes & ears
>larvae & nymphs at back of neck
-CS:
>transmit Babesia canis, Ehrlichia canis, RMSF
>tick paralysis
-diagnosis: ID of tick
-treatment & prevention:
>removed manually
>reg application of Acaricides
Describe Rhipicephalus (Boophilus) spp.
*Rhipicephalus spp: ‘blue tick’
*R. Annulatus: ‘cattle fever tick’
*R. Microplus: ‘tropical cattle tick’
-host: cattle, other lg host
>quarantine zone
-ID: hexagonal basis capituli, dorsal ridges, short palps
-LC: 1 host tick
>adults on ventral aspect of body
>immature stage in ears
-CS:
>B. Bigemina = bovine piroplasmosis
>Anaplasma marginale = gallsickness
-diagnosis: ID of tick
-treatment & prevention: parasiticides (diff if lactating dairy cattle)
>cattle dipping
Describe Amblyomma spp.
‘Lone star tick, gulf coast tick, tropical bont tick, bont tick’
-host: livestock, dog, cat, human zoonotic
-ID: 8mm unfed/20mm fed, long mouth part, long palps, ornate scutum, banded legs
-LC: 3 host tick
-SOI: adults on head, ears, neck
-CS: long mouthpart = deep painful bites
>Hepatozoon americanum by ingestion of A. Maculatum
>cytauzoon felis
>rickettsial
-diagnosis: ID of tick
-treatment & prevention:
>parasiticides
>diff if lactating dairy cattle
Describe Argasids (soft ticks).
-no scutum
-leathery tegument, spinose & bumpy
-mouthparts ventral
-nymphal stages in LC
Describe Otobius spp.
‘Spinose ear tick’
-host: livestock, dogs, humans zoonotic
-ID: mouthparts ventral, spines
-LC: adults not on animal & dont feed
>larvae & nymphs on host & feed
CS:
>ear canal affected
>heavy infestation = anemia
T&P: topical acaricidal in ear & treat premises
Describe Argas spp.
‘Fowl tick’
-host: domestic & wild fowl
-ID: soft tick, 5mm, leathery, textured body, lateral line/crease, genital pore lg in female
-LC: feed during night, survive arid conditions, freq feeding = transmit pathogens
-SOI: on skin (hide during day)
Describe order Acari (mites).
-burrow into host epi (sarcoptes, notoedres)
-nonburrowing = on skin surface (chorioptes, psoroptes, cheyletiella)
-restricted to area of body = Otodectes
Describe Sarcoptes scabiei.
‘Sarcoptic mange mite, itch mite, scabies mite’
-host: domestic animals & humans zoonotic
-ID: round, legs short, females larger
-LC: ELNA
-SOI: skin epi = hairless areas, lateral elbow, pinna of ear
-CS: erythema, scale & crust formation, lesion of follicular papules, areas of erythema, crust of dried serum & blood, pruritus, thickened skin, itching
-diagnosis: skin scrape
-T&P: MCLs (treatment of pet cures human too)
Describe Sarcoptes scabiei in swine.
-mode of transmission:
>sows to piglets during suckling
>boars to gilts
*piglet signs appear within 3wk of birth
-CS:
>scratching & lose condition
>lesions are wheals = erythema around eyes, snout, ears, front of hock
>scabs
>wrinkled skin, covered in crusty lesions, thickened
>lesions progress to hyperkeratosis
-diagnosis: wax in ears
>pruritus is indicator of infestation in sows & piglets
-T&P: treat sow before farrowing (birth) & MCLs
Describe sarcoptes scabiei in cattle.
-SOI: epi skin
-CS:
>most severe cattle mange
>mild infection = scaly skin
>severe infection = thickened skin
>downgrade of hide, drop in meat & milk production (economic loss)
-diagnosis: skin scrape
-T&P: MCLs & eprinomectin for lactating dairy cattle
Describe Notoedres cati.
‘Notoedric cat mite’
-host: cat, dog, rabbit
-ID: looks like smaller sarcoptes
-SOI: head
-diagnosis: skin scrape
Describe Knemidocoptes spp.
‘Scale leg/face mite’
-host: chicken, turkey, caged birds
-ID: adults spherical & look like sarcoptes
-LC: entire LC on host
-SOI: under scales of leg, comb, wattles, neck
-CS: inflammation & keratinization of skin of leg/face (beak)
>lameness
>malformation of feet
-diagnosis: ID of mite
Describe Chorioptes Bovis.
-hosts: cattle, sm ruminants, equids
-ID: rounded mouthparts, suckers at end of stalks
-LC: nonburrowing ELNA
>females lives 4-6wk & lay 90 eggs
-SOI: tailhead, udder, legs
-CS: late winter = mild condition
>damage hide
-diagnosis: skin scraping
-T&P: louse treatment & MCLs (eprinomectin) pour on in lactating dairy cattle
