Acari 1 Flashcards
Arachnids
-identification
- nymphs and adults: four pairs of legs
- larvae: 3 pairs of legs
- body: cephalo-thorax and abdomen
- no antennae
- palps
Ixodidae
hard ticks
Ixodid
-LC
-time taken to complete its LC depends on species of tick, environmental conditions, availability of suitable hosts
Ixodids
-damaging effects
- suck blood
- lesions from mouthparts predispose for other infections
- transmission of dz
- tick paralysis
Ixodes
- common name
- hosts
- Black-legged tick or deer tick
- all mammals & birds & HUMANS. Larvae and nymphs of some species feed on mice and adults on deer
Ixodes
-indentification
-small dark brown, no festoons, long palps, inornate scutum. Anal groove forms an arch anterior to anus
Ixodes
-LC
- Three host tick
- requires adult females to engorge in fall, overwinter and lay eggs in spring. However, when adult females do not find suitable host, LC will take longer to complete
- when same delays occur w/ other tick stages, development will also take longer, up to 4 yrs
Ixodes
-site of infection
-skin. all over body; especially axilla inguinal region, face and ears
Ixodes
-pathogenesis & lesions.CL
- paralysis in animals
- local skin rxns to bites
- transmits Borrelia burgdorferi (Lyme Dz), granulocytic anaplasmosis and human babesiosis
Ixodes
-Dx
engorged females seen easily
Dermacentor
- common names
- Dermacentor variabilis
- D. andersoni
- D. variabilis: american dog tick
- D. andersoni: rocky mt. wood tick
- D. albipictus: winter or elk tick
- D. nitens: tropical horse tick
Dermacentor
-Hosts
-larvae and nymphs feed on small rodents. adults feed on dogs, large hosts, humans. Most common tick on dogs in North America
Dermacentor
-identification
-rectangular basis capituli, short palps, ornate scutum, festoons
Dermacentor
-LC
- 3 host tick
- to complete LC several take months-years
Dermacentor
-site of infestation
skin around head and neck
Dermacentor
-pathogenesis & lesions/CS
-transmits Rocky Mt Spotted Fever (RMSF), sytauxzoonosis, tularemia, tick paralysis
Rhipicephalus sanguineus
- common name
- host
- brown dog tick or kennel tick
- dogs and humans. most common in southern US
Rhipicephalus sanguineus
-ID
-hexagonal basis capituli, inornate scutum, short palps, festoons
Rhipicephalus sanguineus
-LC
-3 host tick. tick has adapted extremely well to indoor living
Rhipicephalus sanguineus
-site of infestation
- skin
- adults prefer skin b/t toes and ears, larvae and nymphs often at the back of neck
Rhipicephalus sanguineus
-pathogenesis & lesions/CS
-transmits babesia and ehrlichia canis, transmits many infectious organisms and RMSF
Ticks in dogs and cats:
Tx & prevention
- ticks can be removed manually
- regular application of acaricides
Rhipicephalus (Boophilus)
- common name
- host
- Rhipicephalus: blue tick
- R. annulatus: cattle fever tick
- R. microplus: tropical cattle tick
- cattle & other large hosts
Rhipicephalus (Boophilus)
- identification
- LC
- site of infestation
- hexagonal basis capituli, prominent dorsal ridges, short palps
- LC: 1 host tick
- adults on ventral aspects of body, immature in ears
