Parasitology - Exam 1 - lecture 8 (Ticks)

Question 1

What are the main classes of ticks

Answer 1

• Ixodid (hard ticks)
• Argasid (soft ticks)

Question 2

Discuss hard ticks vs soft ticlks

Answer 2

Question 3

Regharding Hard ticks (ixodae), discuss morphology (for LAB EXAM ONLY< NOT LECTURE EXAM)

Answer 3

Question 4

Regarding Ixodae ticks, discuss the tick mouthparts

Answer 4

• Chelicerae: cut into skin
• ## Hypostome: used to sucl blood/insert salivary proteins barbed for firm attachment to flesh

Question 5

Discuss enogrged vs unengorged ticks

Answer 5

Engorged vs unegorged female ticks
attached female ticks get larger over the course of sveral days as they feed on bloood

Question 6

Discuss the life cycle of hard ticks

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Answer 6

• Larva, nymph, and adults all require a blood meal
• Female lay eggs in the envionrment
• Larval ticks (sed ticks) hatch out and “quest” for a host and hop on
• :arval ticks get a blood meal from their hst and are then able to molt into nymphs
• Nynphs take a blood meal from their host and molt into adults
• adults take a blood meal - female becomes massively enorged and falls off host

Question 7

What are the two different tyopes of lifecycles for hard ticks?

Answer 7

• One host ticks
• ## three host ticks

Question 8

Discuss the one host ticks lifecycle

Answer 8

One host ticks: once the larval tick finds a host, the tick remians on the host through all the life cyclke stages until the female falls off to lay her eggs

Question 9

Discuss the three host tick lifecycle

Answer 9

Three host ticks –> mosy species of ticks in the US are this
- each life cycle finds a new host to take a meal from
- Molting and egg klaying occur in the enivonrment

Question 10

q

Discuss the effects on host of hard ticks

Answer 10

• Direct effects:tick paralysis; anemia
• Indirect effects –> disease transmission

Question 11

Discuss tick paraklysis in relation to hard ticks

Answer 11

Tick paraltysis:
- Tick saliva can contain a neurotioxin that causes an ASCENDING parallysis
- Dose dependent: the larger the naimnal the more tick are needed to result in paralysis

Hindwuarter incoordination (ascending parlysis begins here) –> hindwuarter parlysis –> foelimb paralysis –> repsiratory muyscle paRALYSIS

Question 12

Discuss the twi different types of disease transmission when considering hard ticks

Answer 12

• Transtadial transmission: one life cycle stage picks up the disease from an infected host and transmit the diseasse to the next host after molting
• Transovarial transmission: adult tick transmits pathogens to her eggs, and the disease is mainatoned between generations

Question 13

Discuss the different species of Ixodes ticks (hard ticks)

Answer 13

• Blacklegged tick:
• ixodes scapularis
• ixodes pacificus

Question 14

Discuss disease transmission and the life cycle for Hard ticks: Ixodes species

Answer 14

• Life cycle: 3 host tick –> ;arva and nymphs prefer mice; deer hist adults. Note that Mice are the reservoir host for Lyme disease
• disease transmission: Both ixodes species transmit: Borrrelia burgdoferi (lyme disease) and anaplasma phagocytophilum

Question 15

Wjhat does the Rhipicephalus species of tick look like and discuss the basics of it

Answer 15

Rhipicephalus sanguineus –> Brown dog tick
- Life cycle: 3 host tick (all stages prefer dogs, meaning the nymph, larva, and adult stage all prefer the dog)
- Disease transmission: Erhlicia Canis; babesia canis

Question 16

What species of hard icks infect cattle?

Answer 16

• ## Rhipicephalus annulata/R. microplus are c attle ticks

Question 16

What does the Dermacentor tick look like?

Answer 16

• Beutifally ornamented with small moutharts
• Have festoons

Question 16

Regarding Hard ticks, discuss the Dermacentor spp and its life cycle yada yada yada

Answer 16

Dermacentor sp:
- **Dermacentor veriabilis ** - American dog tick
- dermacentor andersoni - Rocky mountain wood tick

Life cycle: 3 host tick –> very broad host range

Disease transmission:
Ricketsiaa ricketsiaa –> rocky mountain spotted fever
Tulremia
Anaplasma marginale

Question 16

Conaisering tick (hard ticks), which one most commonly cuases tick paralysis in the US?

Answer 16

• D andersoni

-

Question 16

Discuss Dermacenot spp (dermacenot albipictus)

Answer 16

• Dermacentor albipictus –> winter tick, ghost tick, moose tick

Life cycle: 1 host tick: moose deer, elk, beavers, bears, horses, and dogs
Causes extreme ahir loss in mooose –> can lead to death from exposure

Question 17

Discuss the Amblyomma spp of hard ticks

Answer 17

• amyblomma americanum
• amblyomma maculatam

Question 18

Discuss the life cycle, disease transmission and distiurbutioon of the Lone star tick

Answer 18

The Lone star tick is the amyblomma americanum
Life cycle: 3 host tick –> hosts (host ramnge is very broad)
Disease transission: 1) cytazauxzoon felis; 2) tularemia 3) Southern tick associated rash illness

Bobcats are the reservoir host and theyre not affected by it

Question 19

Discuss the Amyblomma maculatum species of tick

Answer 19

• “The gulf coast tick”
• Life cycle: 3 host tick –> host rnage is very broad
• Disturbution: gulf coast
• Disease transmission: Hepatazoon americanum

Note that the reseveoir host is a beaver while the disease is transmitted by the tick that affects dogs; its a protozoan supposedly

Question 20

Which tick is the asain longorned tick

Answer 20

Asian long horned tick –> Haemaphysalis longicornis

• Note that it ois very invasive
• Capable of transmitting theirleria orientalis –> pathogenic to cattle –> causes bovine infectious anemia
• reproduces pathogenetically (no males required)

Question 21

Discuss the control and prevention for hard ticks

Answer 21

• small animals: selamectin is probably the best macrocyclic lactone to use for this
• also can use: fipronil; flumethrin; isoxazolines

Large animnals:
- pyrethroids
- organophosphates
- macrocyclic lactones

Question 22

Regarding soift ticks, dicsuss the basics of Argasidae

Answer 22

Soft ticks: Otobius sp –> “Spinose Ear ticks”
- Life cycle: 1 host
- Adult are free living
- female lay eggs in the soil
- larvae get on animal and into the ear
- larvae molt to nymphs and remian in the ear
- When ready to molt, bymohs drop to the griound and molt to aduklts
- Broad host range –> deer, sheep, cattle, horses, dogs and humans
-

Question 23

Regarding soft ticks, discuss Otobius spp in terms of clinical signs, disease transmission and treatment

Answer 23

Clinical signs and effects on host:
- irritation: Bites are painful > loss of ocndition
- Secondary infections> Otitis media, otitis interna > Encephalitis
- Disease tranmision: Q fever –> Coxiella Burnetti
- Tretment: Any acaride, applied to the ear

Question 24

Regarding soft ticks, discuss Ornithodoros spp

Answer 24

Pajarello tick –> Ornithoros spp
Prefers cattle and deer
Transmits bacteria that causesnepizootic bovine abortion (foothilll abortion)