arthropods - mites - prostigmatids

Question 1

progstigamatid mites characteristics

Answer 1

stigmata in front of legs
palpal claws
body shape - cigar shapes

Question 2

mesostigmatid mites characteristics

Answer 2

stigmata located mid-body
peritreme: breathing tube, opens at stigma and runs anteriorly
legs: all originate from anterior 1/2 of body; tarsal claws at ends of legs

Question 3

astigmatid mites charcterisitcs

Answer 3

no stigmata
legs: 2 anterior pairs, 2 posterior pairs, tarsal suckers on pedicels

Question 4

mite life cycle

Answer 4

egg
larva - 3 pairs of legs
nymphs - some species have >1 nymph stage
adult

-PPP = 2 to 4 weeks
-adults live 2wks to 2 months
-adult females lay 1-5 eggs per day after mating
-most mites live entire life ON host

Question 5

mite transmission

Answer 5

-direct contact: animal to animal; close, skin to skin

Question 6

mite patho

Answer 6

-most mites invade skin
-some invade ear canal, nasal cavity, lungs
-patho results from mite activity:

mites burrowing and biting
depositing eggs
hypersensitivity reaction to mites

Question 7

clinical signs for skin mites

Answer 7

-dermatitis: “mange”
skin inflammation – erythema (redness)
may be pruritus (itchiness)

Question 8

clinical signs for skin mites

Answer 8

-dermatitis: “mange”
skin inflammation – erythema (redness)
may be pruritus (itchiness)
self trauma due to scratching
alopecia
crust/scabs
-secondary skin infections common

Question 9

other clinical signs

Answer 9

ear canals: ear pruritus, dark/dry/crusted debris

nasal cavity: sneezing, head shaking, rhinitis, pawing at ease, epistaxis

lungs: parasitic pneumonitis, cough, dyspnea

Question 10

skin mite diagnosis

Answer 10

1. skin scraping: deep scrape for demoted; superficial for sarcoptes and others
2. hair pluck = trichogram
3. acetate tape prep: superficial mites
4. fecal float: may see mites ingested with grooming
5. skin cytology

Question 11

ear mite diagnosis

Answer 11

-otoscope: may visualize mites moving
-microscope exam of ear debris; macerate ear debris in mineral oil and cover slip

Question 12

mite treatment and control

Answer 12

-topical and systemic options
-consider life cycle: often need >1 treatment, re-treat in 2-4 weeks

Question 13

demodex host - prostigamatid mite

Answer 13

many mammals
SA: dogs, cats
LA too host specific

Question 14

demodex site

Answer 14

skin: hair follicles, sebaceous glands
often head, limbs

Question 15

demodex clinical signs

Answer 15

demodicosis, demodectic mange

alopecia, often not itchy
LA: nodules
secondary skin infection common - may be itchy then

Question 16

demodex diagnosis

Answer 16

-deep skin scraping, hair pluck, fecal float
-long, cigar, shape
-4 pairs of stubby legs

Question 17

cheyletiella mite host - prostigmatid

Answer 17

cats, rabbits, dogs

Question 18

cheyletiella site

Answer 18

skin, haircoat

Question 19

cheyletiella clinical signs

Answer 19

walking dnadruff
mild pruuritus
often starts on dorsum

Question 20

cheyletiella diagnosis

Answer 20

examine haircoat
acetate tape preparation
fecal float

Question 21

cheyletiella treatment

Answer 21

can live off host several days
treat host + environemnt

Question 22

sarcoptes mite host - astigmatid

Answer 22

many: host-adapted species
SA: dogs, cats, rabbits, ferrets
LA: horses, cattle, pigs

people – zoonotic

Question 23

sarcoptes site

Answer 23

skin
distribution: ear margins, lateral tarsi and elbows

Question 24

sarcoptes clinical signs

Answer 24

sarcoptic mange:

intense pruritus, alopecia, crust, erythema

Question 25

sarcoptes diagnosis

Answer 25

superficial skin scraping
-difficult to find
-globose body
-pedicels: long, unsegmented
-anus located terminally

Question 26

psoroptes host - astigmatid

Answer 26

cattle, horses, sheep, goats
special species: rabbits

Question 27

psoroptes site

Answer 27

LA - skin; especially tail region, shoulders
rabbits - skin: ears (pinnae)

Question 28

psoroptes clinical signs

Answer 28

psoroptic mange
-pruritus
-dermatitis: alopecia, crusting, erythema

Question 29

psoroptes diagnosis

Answer 29

skin scraping
-pedicels: long
-segmented: 3 segments

Question 30

octodectes host - astigmatid

Answer 30

cats, dogs, ferrets, foxes

Question 31

octodectes site

Answer 31

ear canals

Question 32

octodectes clinical signs

Answer 32

ear pruritus
otitis externa: otic debris dark and try

Question 33

octodectes diagnosis

Answer 33

microscope exam of ear debris in mineral oil
-mites and eggs
-pedicels: short, unsegmented

Question 34

chorioptes host - astigmatid

Answer 34

LA: cattle, horses, sheep, goats
special species: rabbits

Question 35

chorioptes site

Answer 35

LA: skin; especially tail, legs
rabbits: skin – ears (pinnae)

Question 36

chorioptes clinical signs

Answer 36

chorioptic mange
-pruritus (variable)
-dermatitis: alopecia, crusts, erythema

Question 37

chorioptes diagnosis

Answer 37

skin scraping
-pedicels: short, unsegmented

Question 38

knemidokoptes host - astigmatid

Answer 38

birds

Question 39

knemidokoptes site

Answer 39

skin: face, legs

Question 40

knemidokoptes clinical signs

Answer 40

-proliferative, crusted lesions
-legs, base of beak, vent
-characteristic lesions

Question 41

knemidokoptes diagnosis

Answer 41

-microscopic exam of skin crusts
-skin scraping
-mites have globose shape
-pedicels: females - none, males - long, unsegmented

Question 42

notoedres host - astigmatid

Answer 42

cats, rabbits, rats

Question 43

notoedres site

Answer 43

skin - ears, face, distal extremities

Question 44

notoedres clinical signs

Answer 44

intense pruritus
crusting
alopecia

Question 45

notoedres diagnosis

Answer 45

skin scraping
-pedicels: long, unsegmented
-anus located dorsally