arthropods - arachnids - ticks

Question 1

what are the 2 families of ticks

Answer 1

ixodidae (hard ticks)
argasidae (soft ticks)

Question 2

tick morphology

Answer 2

adults: four pairs of legs
fuses body segments: head + thorax + abdomen

Question 3

ixodid: identifying characteristics

Answer 3

mouthparts: projects cranially
scutum: present
females vs males:
-scutum is smaller in females

Question 4

argasid: identifying characterisitics

Answer 4

mouthparts: not visible from dorsal side
scutum: none
leathery, wrinkled
some have spines

Question 5

general tick life cycle

Answer 5

-eggs
-larve: 6 legs
-nymph: 8 legs
-adults
-ixodid: 1-3 years, argasid: 1 month to years

Question 6

tick life cycle: one-host tick

Answer 6

egg: laid on ground
hatches
larva: finds host and feeds
molts on host
nymph: feeds on same host
drops to ground OR molts on host
adult: nonparasitic or feeds on same host
non-parasitic on ground OR mates and drops to ground
egg: laid on ground

Question 7

tick life cycle: three-host tick

Answer 7

egg: laid on ground
hatches
larva: finds host #1 - feeds and drops off
molts
nymph: finds host #2 - feeds and drops off
molts
adult: finds host #3 - feeds, mates, and drops off
female lays eggs
egg: laid on ground

Question 8

basic tick pathology and clinical disease

Answer 8

-usually few clinical signs
-bite wounds
-annoyance
-blood loss: anemia if many ticks
-vectors: many disease transmitted by ticks
-tick paralysis: toxic substance in saliva of some ticks; neurological signs - weakness, paralysis

Question 9

disease tramission between ticks

Answer 9

interstadial transmission:
-disease organism acquired from host by larval or nymph tick
-organism carried through molt to nymph or adult tick

transovarian transmission:
-disease organism passed from adult female tick to eggs via ovaries
-only way one-host tick can serve as vector

Question 10

tick treatment

Answer 10

-tick removal
-gently cleanse patient skin and wash hands
-NOT mineral oil, petroleum jelly
-goal = remove as soon as possible

Question 11

tick prevention

Answer 11

-avoid tick habitats
-tick checks
-drugs –> ascaricides: act by prevention tick nervous system function

Question 12

ixodid tick feed behavior

Answer 12

-3 host tick
-each stage feeds in one large meal
-then spends time off host

Question 13

ixodes host

Answer 13

many

Question 14

ixodes characteristics

Answer 14

tiny
inornate
no festoons
anal groove

Question 15

ixodes scapularis patho

Answer 15

-vector or intermediate host:
bacterial disease = Lyme = borrelia burgdorferi, anaplasma, ehrlichia
protozoal disaces = babesia spp.

-tick paralysis

Question 16

dermacentor species host

Answer 16

many - dogs, cattle, horses, wildlife, people

Question 17

dermacentor characterisitcs

Answer 17

3-host tick
ornate
festoons
rectangular basis capitulum

Question 18

dermacentor patho

Answer 18

-tick paralys: main cause
-vector/intermediate host: bacterial diseases - anaplasma, ehrlich, rickettsia ; protozoal disease - babesia spp.

Question 19

rhipicephalus sanguineus host

Answer 19

dogs, people

Question 20

rhipicephalus sanguineus other name

Answer 20

brown dog tick

Question 21

rhipicephalus sanguineus characteristics

Answer 21

3-host tick
inornate
festoons
hexagonal basis capitulum

Question 22

rhipicephalus sanguineus patho

Answer 22

-vector/intermediate host: bacterial disease - rickettsia rickettsi, ehrlichia Canis ; protozoal diseases - babesisa canis

Question 23

rhipicephalus annulatus host

Answer 23

cattle

Question 24

rhipicephalus annulatus characteristics

Answer 24

1-host tick
inornate
no festoons
hexagonal basis capitulum

Question 25

rhipicephalus annulatus patho

Answer 25

vector: protozoal disease - babesia bigemina

Question 26

amblyomma host

Answer 26

many - domestic animals, reptiles, people

Question 27

amblyomma characteristics

Answer 27

ornate - female has a white spot on scutum
festoons
very long mouthparts

Question 28

amblyomma patho

Answer 28

-tick paralysis
-vector/intermediate host: bacterial disease - anaplasma phagocytophilum, rickettsia rickettsii, franscisella tularensis, some borrelia species

Question 29

argasid feeding behavior

Answer 29

-much time spent off host (in host bedding, nesting materials, cracks and crevices, housing)
-feed often and for short periods
-most species rarely found on host
-active at night

Question 30

otobius species host

Answer 30

cattle
also reported in horses, sheep, dogs, people

Question 31

otobius characteristics

Answer 31

one-host tick
soft tick features
violin shape
cuticle covered in spines

Question 32

otobius patho

Answer 32

-decreased production: due to annoyance
-otitis externa: larvae and nymphs live in ear canals
-disease vector: suspected vector for bacterial disease Q fever