Parasitic Arachnids: Ticks and Mites

Question 1

What parasite’s entire life cycle occurs on the host, consisting of eggs, larva, nymph, and adult stages where the adult mainly lives on the surface of skin (in the ear canal)

Answer 1

Mites

Question 2

An animal comes into the clinic with signs of head shaking, rubbing, and head shyness. You notice truncal dermatitis (mane and tail) with secondary lesions that are scaly/crusted/poorly-demarcated alopecia. You find a small parasite in the ear canal as well as the mane and tail – what parasite is this?

Answer 2

Psoroptes

Question 3

You find a parasite on the legs/abdomen/udder/base of tail of cattle and horses worldwide. The animals are itching and you see suckers on pedicles that are unsegmented. It is winter time, and this is impacting milk production. The parasites are non-burrowing surface mites – what parasite is this?

Answer 3

Chorioptes

Question 4

Puppies in a large breeding facility have walking dandruff and red/yellow crusts. You find a non-burrowing parasite feeding on the keratin of the epidermis. What parasite is this?

Answer 4

Cheyletiella

Question 5

A wild dog was found with hyoerkeratosis and alopecia. Parasites have burrowed into the skin in its ears, elbows, flank, and ventrum. What parasite is this?

Answer 5

Sarcoptes scabei

Question 6

A parasite that is often considered normal fauna is found in the hair follicles and sebaceous gland ducts of someone brought into the clinic. Deep skin scrapes were necessary to diagnose this parasite and it can often resolve itself spontaneously. What parasite is this?

Answer 6

Demodex

Question 7

What are the names of the 5 mites listed in class

Answer 7

Demodex, Sarcoptes scabei, Cheyletiella, Chorioptes, Psoroptes

Question 8

What are the life stages of ticks and how many legs do the stages have

Answer 8

Larval (6 legs), nymphal (6 legs), adult instars (8 legs)

Question 9

which arachnids are epidermal parasites

Answer 9

ticks

Question 10

which arachnids can live in skin, the respiratory system, or other organs

Answer 10

mites

Question 11

which two body regions do ticks and mites have and what two body parts are fused

Answer 11

head and body; head and thorax

Question 12

what type of flattened are ticks and mites

Answer 12

dorsoventrally flattened (belly to back flat)

Question 13

which body part bears mouthparts in ticks and mites

Answer 13

gnathostoma/capitulum

Question 14

what body part bears legs and contains internal organs

Answer 14

idiosoma

Question 15

Which types of ticks have only 1 nymphal stage and which have as many as five

Answer 15

hard ticks; soft ticks

Question 16

where does tick reproduction occur and what is the blood meal important for

Answer 16

on the host; laying eggs

Question 17

can ticks fly or jump?

Answer 17

no they can only crawl – they can quest for a host

Question 18

what does the term argasidae refer to

Answer 18

soft ticks

Question 19

what does the term ixodidae refer to

Answer 19

hard ticks

Question 20

Which ticks have long mouth parts

Answer 20

Amblyomma Ixodes

Question 21

Which ticks have short mouth parts

Answer 21

Rhipicephalus Dermacentor

Question 22

Which ticks have ornate white markings on the scutum

Answer 22

Amblyomma dermacentor

Question 23

Which ticks have inornate scutums with no white markings

Answer 23

Rhipicephalus ixodes

Question 24

What type of tick is often established indoors and kennels

Answer 24

rhipicephalus sanguineus (brown dog tick)

Question 25

what are some direct effects of ticks

Answer 25

• blood loss (anemia), inflammation, toxicosis, etc.