Canine/feline mites (year 2)

Question 1

describe the morphology of mites

Answer 1

they are arachnids with no distinct body parts just a mouth and body, adults have 8 legs and larvae have 6

Question 2

what are the two groups of mites

Answer 2

burrowing and non-burrowing

Question 3

name the main burrowing mites in cats/dogs

Answer 3

Sarcoptes scabiei
Notoedres cati
Demodex

Question 4

what does Sarcoptes scabiei cause?

Answer 4

sarcoptic mange

Question 5

describe the morphology of Sarcoptes scabiei

Answer 5

0.2-0.5mm
rounded body
rounded mouthparts
4 pairs of stumpy legs that don’t extend beyond the body
scales/spine on dorsal surface
thumb print pattern from cuticle folds on dorsal surface

Question 6

how is Sarcoptes scabiei transmitted?

Answer 6

via direct contact - highly contagious

Question 7

in what layer of skin is Sarcoptes scabiei found?

Answer 7

superficial

Question 8

how long is the egg to adult lifecycle of Sarcoptes scabiei?

Answer 8

14 days

Question 9

in which species (dogs/cats) is Sarcoptes scabiei infection rare?

Answer 9

cats

Question 10

describe the lifecycle of Sarcoptes scabiei

Answer 10

adults mate on skin surface then females burrowing burrow into the stratum corneum creating tunnels in the keratin and feeding on fluid between cells. The females lay 3 eggs a day in these tunnels that hatch after 3-4 days, they exit the tunnel where they moult to a protonymph then tritonymph and finally an adult

Question 11

how many females are in each Sarcoptes scabiei tunnel and how long are these tunnels?

Answer 11

1 mite

1cm

Question 12

where on the animal does Sarcoptes scabiei first affect?

Answer 12

ears, muzzle, face, elbows

Question 13

is Sarcoptes scabiei seasonal or commensal?

Answer 13

neither seasonal or commensal

Question 14

what are the clinical signs of Sarcoptes scabiei?

Answer 14

intense pruritis, papular lesions, alopecia, crusting, self trauma, secondary bacterial infections

Question 15

how is Sarcoptes scabiei diagnosed?

Answer 15

superficial skin scrapings from margins or lesions (microscopy), serology (ELISA)

Question 16

how is Sarcoptes scabiei controlled/treated?

Answer 16

treat all affected and in contact animals with amitraz/selamectin/moxidectin/imidacloprid

Question 17

what is the usual host for Notoedres cati?

Answer 17

cats

Question 18

describe the morphology of Notoedres cati

Answer 18

rounded body
rounded mouthparts
4 pairs of stumpy legs that don’t extend beyond the body
dorsal anus
thumb print pattern from cuticle folds on dorsal surface

Question 19

how is Notoedres cati transmitted?

Answer 19

via direct contact or fomites - highly contageous

Question 20

describe the lifecycle of Notoedres cati

Answer 20

adults mate on skin surface then females burrowing burrow into the stratum corneum creating tunnels in the keratin and feeding on fluid between cells. The females lay 3 eggs a day in these tunnels that hatch after 3-4 days, they exit the tunnel where they moult to a protonymph then tritonymph and finally an adult

Question 21

how is Notoedres cati diagnosed?

Answer 21

superficial skin scrapings (microscopy), serology (ELISA)

Question 22

what part of the body does Notoedres cati infect first?

Answer 22

face, head, ears

Question 23

what are the clinical signs of Notoedres cati?

Answer 23

pruritus, alopecia, scaling, crusting, erythema, lichenification

Question 24

how is Notoedres cati treated?

Answer 24

selamectin

Question 25

what is Demodex known as, and where does it live?

Answer 25

follicle mite that lives in hair follicles and sebaceous glands of a variety of hosts

Question 26

describe the morphology of Demodex

Answer 26

long cigar shape with 4 pairs of stumpy legs

Question 27

is Demodex comensal?

Answer 27

yes - cannot survive off of host

Question 28

how long is the lifecycle of Demodex?

Answer 28

18-24 days - egg, larvae, protonymph, tritonymph, adult

Question 29

how is Demodex transmitted?

Answer 29

from bitch to pups during feeding

Question 30

when does Demodex become an issue?

Answer 30

when the host is immunosuppressed

Question 31

what are the clinical signs of Demodex?

Answer 31

erythema, pustules, crusts, pruritis, papule, alopecia

Question 32

how is Demodex diagnosed?

Answer 32

deep skin scraping (microscopy)

Question 33

name the three non-burrowing mites found in cats/dogs

Answer 33

Otodectes cynotis Cheyletiella Trombicula

Question 34

describe the morphology of Cheyletiella

Answer 34

0.5mm palp with strong curved claws round body long legs

Question 35

what is Cheyletiella known as colloquially?

Answer 35

walking dandruff

Question 36

where on the host is Cheyletiella found?

Answer 36

dorsal surface between shoulder blades

Question 37

how is Cheyletiella transmitted?

Answer 37

by direct contact and fomites

Question 38

what are the clinical signs of Cheyletiella?

Answer 38

mild pruritis and scaling

Question 39

how is Cheyletiella diagnosed?

Answer 39

grooming host and examining material microscopically

Question 40

what are the licensed treatments for Cheyletiella?

Answer 40

there are none but could use ivermectin or fipronil

Question 41

what is Otodectes cynotis known as?

Answer 41

the ear mite

Question 42

where does Otodectes cynotis infect?

Answer 42

the ear canal of cats and dogs but can spread to neck

Question 43

how long is is the lifecycle of Otodectes cynotis?

Answer 43

3 weeks

Question 44

how is Otodectes cynotis transmitted?

Answer 44

direct contact

Question 45

describe the clinical signs of Otodectes cynotis

Answer 45

brown waxy exudate from ear, itching, head shaking, secondary bacterial infection

Question 46

how is Otodectes cynotis treated?

Answer 46

permethrin ear drops, selamectin

Question 47

what is Trombicula also known as?

Answer 47

harvest mites or chiggars

Question 48

what is special about the larval stage of Trombicula?

Answer 48

they are parasitic

Question 49

when is Trombicula usually found?

Answer 49

late summer and early autumn

Question 50

how does Trombicula infect its host?

Answer 50

climb onto plants and swarm onto host when it comes close

Question 51

how are infections of Trombicula seen to the naked eye?

Answer 51

clumps of orange

Question 52

where are Trombicula lesions usually found?

Answer 52

feet, ventral body, face

Question 53

what are the clinical signs of Trombicula?

Answer 53

erythema, papule, scales, crusts, pustules, pruritis

Question 54

how is Trombicula treated?

Answer 54

fipronil, amitraz repeated treatments