Ticks

Question 1

Ticks are ________ parasites

Answer 1

Obligate blood-sucking parasites

Question 2

T/F: cat’s can’t get ticks because they are good groomers

Answer 2

False

- can still get ticks and tick borne diseases

Question 3

Body parts of ticks

Answer 3

• cephalothorax
• abdomen
  OR, completely fused

Question 4

How many legs do ticks have?

Answer 4

4 pairs = 8 total

Question 5

Do ticks have antennae?

Answer 5

No

Question 6

Do ticks have wings?

Answer 6

No

Question 7

What body parts do ticks not have?

Answer 7

• antennae
• mandibles
• wings

Question 8

What do ticks do have?

Answer 8

• capitulum (mouth parts)
• idiosoma (body)
• legs

Question 9

Capitulum

Answer 9

Composed of: hypostome, palps, and chelicerae

Question 10

What parts of a tick actually enter the host?

Answer 10

Hypostome and chelicerae

Question 11

What does tick saliva contain?

Answer 11

Anticoagulatory factors and anti inflammatory factors to allow for a smooth, clean blood meal

Question 12

What are the 2 main families in the class Arachnida?

Answer 12

Argasidae
- soft (argasid) ticks
Ixodidae
- hard (ixodid) ticks

Question 13

Argasid morphology

Answer 13

• cannot see mouthparts sticking out from a dorsal view
• no scutum due to small blood meals
• leathery integument
• males and females look the same

Question 14

Argasid life cycle

Answer 14

Each stage may use multiple hosts for multiple, quick feedings

• larva, nymph (multiple instars), adult
• females lay multiple small egg batches after each feeding

Question 15

Ixodid tick morphology

Answer 15

• mouthparts seen dorsally and ventrally (seen in larval, nymphal, and adult stages)
• female has partial scutum, male has full scutum
• sexually dimorphic

Question 16

Ixodid life cycle

Answer 16

Each life stage feeds on one host for a single feeding, usually taking about a week

• 1, 2, 3 host life cycles
• larva, nymph, adult
• females lay single large egg batch

Question 17

_____ and _____ stages of Ixodid have a partial scutum

Answer 17

Nymphal and larval

Question 18

All adult ______ ixodid ticks require a warm blood meal

Answer 18

Female

• males do not require blood meal in adult stage
• make egg batch after feeding (20,000 eggs) –> most offspring survive
• will die after making one batch

Question 19

Number of nymphal stages

Answer 19

• > 2 for soft ticks

- 1 for hard ticks

Question 20

Habitat preference of soft ticks

Answer 20

Nidicolous

- tolerate arid environments

Question 21

Habitat preference of hard ticks

Answer 21

Non-nidicolous

- prefer humid environments

Question 22

Argasidae genera

Answer 22

• argas
• ornithodoros
• otobius

Question 23

Ixodidae genera

Answer 23

• ixodes
• amblyomma
• dermacentor
• rhicephalus

Question 24

Argasidae - Argas spp

Answer 24

Hosts include birds and bats

• leathery cuticle, flat body margin (suture line)
• Argas persicus: fowl tick (blue bug) of eastern US

Question 25

Argasidae - Ornithodoros spp.

Answer 25

Hosts include mammals

• leathery cuticle
• rounder margin
• no suture line

Question 26

Argasidae - Otobius megnini

Answer 26

1 host soft tick (cattle, horses)

• larva, 2 nymphal stages feed in same ear
• adult stages do not feed!
• nymphal tegument spiny (spinose ear tick)

Question 27

Which stages of Otobius megnini are parasitic?

Answer 27

Larval and nymphal

Question 28

Passive method of host finding

Answer 28

Ambush/questing

• ticks sit and wait for host, then wave forelegs frantically when sense cues
• requires direct contact!

Question 29

Active method of host finding

Answer 29

Hunting

- leave resting environment to attach (run/walk to) hosts when sense cues

Question 30

What tick is both a hunter and a quester?

Answer 30

Lone star tick (Amblyomma americanum)

Question 31

Ixodes scapularis

Answer 31

3-host tick

• immature: rodents, birds, lizards
• adults: white tailed deer, livestock
• adult stages active in cool weather

Question 32

What tick appears similar to I. scapularis?

Answer 32

Ixodes pacificus

- occurs in western US

Question 33

Black legged tick

Answer 33

Ixodes scapularis

• 2 year life cycle that is important for maintenance of Lyme disease
• life cycle in southern US may be complete in 1 year

Question 34

Location of ______ is key morphological difference between Ixodes vs other hard tick genera

Answer 34

Anal groove

- anal groove of Ixodes encircles anus anteriorly

Question 35

Amblyomma americanum

Answer 35

3 host tick

• all stages: wide host range (prefer white tailed deer)
• high tolerance for warm, humid climates
• very aggressive
• most common tick in southern US

Question 36

Amblyomma maculatum

Answer 36

Gulf coast tick

• markings on scutum similar to Dermacentor variabilis
• A. maculatum has longer moutparts

Question 37

Dermacentor variabilis

Answer 37

American dog tick - 3 host tick

• immature: prefer rodents
• adult: prefer canine hosts

Question 38

Dermacentor andersoni

Answer 38

Rocky Mountain wood tick - 3 host tick

• immature tick: prefer rodents
• adult tick: deer, sheep, cattle, etc

Question 39

Are D. variabilis and D. andersoni found in the same region?

Answer 39

No

Question 40

Rhipicephalus sanguineus

Answer 40

Brown dog tick - 3 host tick

• all stages: narrow host range (found wherever dogs are)
• does not tolerate cold
• infests kennels, houses, etc

Question 41

R. (Boophilus) annulatus

Answer 41

1 host ticks

• prefer cattle
• cattle tick, cattle fever tick

Question 42

R. (Boophilus) microplus

Answer 42

1 host ticks

• wider host range
• southern cattle fever tick

Question 43

______ and _____ eradicated from US

Answer 43

R. annulatus and R. microplus

- reportable!

Question 44

Goals of tick prevention

Answer 44

• kill existing ticks on animal
• repel new ticks/prevent bites
• provide residual activity
• reduce/eliminate stages in environment