Mites Flashcards
What hosts do dermanyssidae and macronyssidae mites parasitize
Birds and rodents, people in buildings when their normal hosts are removed (i.e. Rats exterminated or fledglings leave nest)
Which families of mites are considered mesostigmatid, and what does that imply?
Dermanyssidae, Macronyssidae, Halarachnidia
Mesostigmata - stigma in between legs 3 and 4
What hosts can Ornithonyces be found on
Birds - chickens and people who handle chickens
When would you likely find Dermanyssus on their avian hosts? Why?
Found on host at night - feed at night, hide during the day
Liponyssoides sangineus
Host
Associated Diseases
Host is house mouse
VEctor of rickettsial pox in humans
Which species have long and slender chelicerae with minute chelae
Liponyssoides
Dermanyssus
Ornithonyssus
Physical characteristics
Common species and their hosts
Associated diseases
Type of people affected
Chelicerae much stouter than those of dermanyssidae, readily visible chelae under ordinary magnification
O. Sylvarium - northern fowl mite
O. Bursa - tropical fowl mite
O. Bacoti - tropical rat mite - important in lab mice, intermediate host of ??????????
Stay on chickens and may feed on people handling chicken eggs
Ophionyssus natricis
Host
Treatment
Snakes
Ivermectin
Pneumonyssoides
Family
Host
Associated disease
Halarachnidia
Nasal and paranasal sinuses of dogs
P. caninum - chronic sneezing and epistaxis
Orthohalarachne
Family
Host
Halarachnidia
Respiratory tract of seals
Varroa destructor
Family
Host
Importance
Halarachnidia
Honey bee
Threat to US agriculture - honey production, pollination
What is the defining feature of astigmatids? What types of motes are astigmatids?
No breathing holes, breath through the skin.
Mange mites, some hair-clasping mites, 2 internal parasites of chickens and grain mites
What families are included in group, mange mites and what diseases are associated with them?
Sarcoptide, knemidocoptidae, Psoroptidae
Mange or scabies
Scabies - dermatitis characterized by pruritus, alopecia, and epidermal hyperplasia with desquamation. Rubbing and scratching may lead to oozing serum and blood.
Sarcoptes scabiei
Pretarsi characteristics
Associated disease and animals affected
Pretarsi with long unsegmented pedicels
Sarcoptic mange or scabies in humans, dogs, foxes, horses, cattle (reportable) and others.
Host specificity - when interspecific transmission occurs, resulting dermatitis is atypical and transient
Notoedres
Hosts
Pretarsi characteristics
Associated disease
Parasites of cats, rats, rabbits, occasionally and temporarily humans
Pretarsi have long unsegmented pedicels
Face mange in cats (Notoedres cati) starts on medial edge of pinna and spread to face, paws and hindquarters - alopecia, hyperkeratosis
Knemidokoptes
Species and their associated diseases
Animals affected
Knemidokoptes mutans - scaly leg in chickens, turkeys, pheasants and other galliinaceons birds - mites burrow in epidermis causing scales to lift and loosen, legs thickened and deformed
K. Pilae and K. Jamaicensis - mange od the legs, base of beak, vent area of parakeets, and back of canaries
Psoroptes
Pretarsi characteristics
Species, associated diseases and affected animals
Pretarsi have long, 3 segmented pedicels
Psoroptes ovis - psoroptic mange (reportable) in cattle, sheep and horses
Psoroptes cuniculi - ear canker in rabbits, less severe form of otis acariasis in goats and horses
Where on the skin does Psoroptes ovis live?
Does not burrow, but remains at base of hairs - pierce skin with stylet-like chelicerae
Resulting exudate on of serum hardens to form a scab
What are the Pretarsi characteristics of Chorioptes bovis?
Short unsegmented pedicels on first, second and fourth pairs of legs of the female and all the legs of the male
Chorioptes bovis
Hosts
Where on the host does this mite prefer to feed?
What do they eat?
Superficially dwelling
Preference for tail, escutcheon and legs of cattle, usually inflate winter, mildly pruritic
May be found on tail and legs of horses, sheep, and goats and in the ear canal of rabbits
What is the scientific name for ear mites?
Pretarsi characteristics
Hosts
Otodectes cynotis
Short unsegmented pedicels on first and second legs of the female and all legs of the male
Infests external ear canal and adjacent skin of dogs, cats, foxes, and ferrets causing intense irritation
Lynxacarus radovskyi
Family
Common name
Hosts
Geographic distribution
Astigmata
Hair-clasping mites
Domestic cats (cling to hairs imparting a scruffy appearance
Florida, Puerto Rico, Hawaii, Australia, Fiji
Demodex
Family
Physical characteristics
Prostigmata
Tiny worm-like mites with short, stubby legs
Name two species of demodex that live in the skin of the human face?
What portion the skin
Demodex folliculorum - hair follicles in human face
Demodex brevis - sebaceous glands in human face
Canine Demodex
Host
Transmission
Disease
Clinical signs
Comparison
Demodex canis: Present in small numbers on the skin of most normal dogs in hair follicle
Transferred from dams to puppies during nursing
Demodactic mange in immunodeficient puppies 3-6mo old
Circumscribed areas of erythema and alopecia around the eyes, mouth and over bony projections on the extremities. No evidence of pruritis.
D. injai: about twice the length of D. Canis
Mainly found in sebaceous glands
Dorsal seborrheic dermatitis
D. cornei: shorter and. Stouter than D. canis
Lives in stratum corneum
Signs similar to D. canis
Demodex cati
Disease severity and localization
Rarely noticed
Head and ear canals
Demodex gatoi
comparison to demodex cati
More superficially dwelling than D. cati, found in stratum corneum of cats.
Shorter and broader than D. cati
Demodex bovis
Host
Associated disease
Usually normal fauna of bovine skin: eyelids, vulva, scrotum
Can cause pinhead to egg sized nodules on neck and forequarters
Demodex phylloides
Host
Lesion
Localization
Pigs
Nodules around eyes and on snouts, later spread to underside of body
Demodex caprae
Host
Lesion
Milk goats
Nodular dermatitis
Chelyletiella
Species and their preferential host and associated disease
Cheyletiella yasguri: dogs, walking dandruff
Ch. blakei: cats
Ch. parasitivorax: rabbits
Humans may serve as accidental or transitory host
Psorogates
Family
Hosts and associated lesion
Prostigmata
Mice and primates
May cause mange-like condition
Myobiidae
Distinguishing features
Species and preferred host
Clinical signs
Causes of outbreak
first pair of legs modified for clasping hair
Myobia musculi - lab mice
Radfordia ensifera - lab rats
Alopecia and erythema of dorsal neck region, self inflicted damage in severe cases
Stress and overcrowding
Harpyrhynchidae
Hosts
Lesion and localization
Birds
Burrow in feather follicles or form large crusted cysts in skin
Syringophilidae
Host
Localization
Associated disease
Birds
Lumen of feather quills
Nonpathogenic
Trombiculidae
Larvae
Host and localization
Larvae called chiggers, only parasitic life stage
On skin or in ears of cats or dogs, or on faces or pasterns of ungulates, or under wings and around vents of birds
Tarsonemidae
Important species and it’s host
Acarapis woodi - tracheal mite of honeybees
Pneumonyssus
Family
Host
Associated disease
Halarachnidia
Lung parenchyma of most (or all) Macaca mulatta monkeys (Pneumonyssus simicola)
Pulmonary acariasis - pinhead (or >) sized lesions with a whitish or yellow foci that have soft or empty centers and contain mites and a black pigment in the center
