Parasitology Final Flashcards
Common name for Musca Autumnalis

Facefly
What type of Muscoid fly is the Facefly?
Non-biting muscoid –> sucking labia (no piercing parts)
L.C. of Musca autumnalis?
Lay eggs in cattle dung < 1 h. old
eggs hatch w/in a few hrs.
maggots emerge & feed on fecal matter
Grow to 3rd instar stage & pupate
10-20 d. later emerge as adults
M. autumalis is the IH of what?
Thelazia (cattle eye worm)

What is M. autumalis a biological vector of?

Morxella bovis
causative agent of infectious bovine keratoconjunctivitis or pink eye.
What is the habitat of M. autumnalis?
prefer cattle & horse faces
fence & vegatation
DO NOT ENTER BUILDINGS
Key characteristics of Stomoxys

biting muscoid fly
protruding bayonet-like mouthparts
males & females suck blood
checkerboard pattern
Where do Stomoxys prefer to lay their eggs?
decaying vegetative matter
What is Stomoxys the IH for?

Habronema (horse stomach worm)
cutaneous deposition of L3 Habronema can cause skin ulcers if enters broken skin
What is the common name for Stomoxys?
stable fly
What is the common name of Haematobia?

horn fly
Characterisitics of Haematobia?
Biting Muscoid fly
bayonet-like mouth parts
male & females suck blood
Habitat of Haematobia?
prefer pastures
toplines of animals (whithers) and around the horns of cattle
cattle > horses
Where do Haematobia like to lay their eggs?
fresh manure < 30 min old
What are Haematobia the IH of?
Stephanofilaria stilesi
(filarial parasite of skin of cattle)
What is the economic importance of Muscoid flies?
- decreased production
- meat, milk, hide
- allergies
- stinging
- annoyance
- blood loss
- parasite & dz vectors
What is the common name of Melophagus ovinus?

sheep ked
Characteristics of Melophagus ovinus?
Hippoboscid fly
wingless dipteran
male & females suck blood
Habitat of Melophagus ovinus?
live entire life in the wool of sheep
L.C. of Melophagus ovinus?
“Modified” complex metamorphosis
larvae develop inside female
extruded larvae pupate w/in few hrs
pupul case remains glued to wool
adult fly emerges in 3-6 wks
(temp dependent)
How do you spell Dr. P’s last name?
Pinckney
What is Facultative Myiasis?
a. k.a Secondary Myiasis
* Musca domestica*, blow flies or bottle flies
normally free-living
Under certain circumstances they may adapt themselves to a parasitic existence
What is myiasis?
parasitic infestation of a living organs or tissues by dipteran larvae
What is “Strike”?
any cutaneous myiasis in sheep
What is Obligatory Myiasis?
a.k.a Primary Myiasis
parasite is dependent upon the animal for a certain portion of its L.C.
MUST utilize a host to complete its L.C.
What is the common name of
Cochliomyia hominivorax?

Primary (American) Screwworm
Characteristics of Cochliomyia hominivorax?
any warm-blooded animal (humans!)
metallic blue, green body and reddish orange face.
mature larvae –> distinct bands of spines w/ 2 deeply pigmented breathing tubes 1/3 of their length
(looks like screw)
Is Cochliomyia hominivorax reportable if found on lifestock?
YES!!!!
How can we control & eradicate
Cochliomyia hominivorax?
sterile male release technique
females only breed once then die
Where do Cochliomyia hominivorax prefer to lay their eggs?
in clean (fresh) wounds
require living tissue
Characteristics of Complex Metamorphosis
- Developmental stage bears no resemblance to adult
- Worm like larva
- Pupa is the resting stage
- Adult emerges from pupa
Characteristics of “Modified” Complex Metamorphosis
- Female retains larvae in her body
- Eggs laid on host
- Eggs pupate shortly after being laid
What is the common name for Hypoderma**?

- Cattle Grub
- Cattle Heel Fly
- Ox Warble
- Warble Fly
What is the characteristics of Hypoderma?
- Complex Metamorphosis
- Obligatory Myiasis
- Bumble bee- like appearance
- NO fxning mouth parts
When do you treat Hypoderma?
Summer or Early Autumn
(will get esophagitis, bloat or spinal canal lesions if TX during winter)
Which Hypoderma stages cause pathogenesis in cattle?
Adults - fright b/c look like bumblebees
Young- “Gadding” (severe damage to hide)
What happens if you rupture the larva of Hypoderma?
Localized inflammation & abscess formation
What species are affected by Oestrus?

Sheep & Goats
Characteristics of Oestrus?
- No fxning mouth parts
- Active during summer months
- Modified Complex Metamorphosis
- Obligatory Myiasis
- RARELY parasitize humans & other domestic animals
What is “False Gid”?
when Oestrus larvae penetrate the cribiform plate & mirgrate to the brain
What is the common name of Gasterophilus?
Horse Stomach Bot Fly
Characteristics of Gasterophilus?
- Honeybee like appearance
- No fxning mouthparts
- Complex Metamorphosis
- Obligatory Myiasis
- Long prepatent period (10-12 mo)
- No issues unless purfurate the stomach
L.C. of Gasterophilus?
- Females lay eggs on legs, nostrils or lips of horses
- larva migrate to stomach & mature
- Larva crawl back up esophagus & expelled
- Larvae pupaute in ground
- Emerge as adults
What is the common name for Cuterebra?

Wolves worms
Warbles
Characteristics of Cuterebra?
- Black & white looking honeybee
- No fxning mouth parts
- Mature larva are black w/ spines
- Complex Metamorphosis
- Obligatory Myiasis
What is the L.C. of Cuterebra?
- Lay eggs near rodent borrows
- Larva catch rides on passing rodents
- Larva enter through physiological orifices
- Larva migrate in SQ tissue & generate large inflammed cysts
- Drog out & pupate on ground
What can Cuterebra cause in cats, dogs & humans?
- CNS signs b/c moving through cribiform plate
What are all maggots?
BUTT BREATHERS!!!!!
(ewwww)
Characteristics of fleas?
- Not host specific
- Both sexes are bloodsuckers
- ONLY adults are parasitic
- Larvae are “maggot like” & eat flea dirt
Which flea commonly infects Poultry?
Echidnophaga
Common name for Echidnophaga?
Stick-tight fleas
What flea transmits the Plague?
Xenopsylla
What are some C.S. of Echidnophaga in birds?
Lesions on comb & wattles
What insect is the culprit of a “Bubo”?
Xenopsylla
What is the difference between Sucking & Chewing lice?
Chewing lice have big, fat heads that are wider than their thorax
What type of lice is Trichodectes? Who does it affect?
Chewing louse of the Dog
(remember it’s an insect- has 6 legs!)
What type of lice do birds get?
Chewing Lice ONLY
What species are affected by Linognathus?
- sheep & goats
- dog, cattle & horses (via Dr. P)
Characteristic of Linognathus?
1st pair of tarsal claws in smaller than the other pairs
What type of lice to cats get? Characteristics?
- ONLY chewing lice - Felicola
- triangular head
What species does Damilinia infect?

Chewing louse of horse
(can do rumis too)
What is the sucking louse that infects horses?
Haematopinus
Characteristic of Haematopinus?
All tarsal claws are equal size
Which species of lice is the “Hog Louse”?
Haematopinus suis
Solenopotes only infect what animal?
moo cows!!
What is the common name for Pthirus?

HUMAN crab louse
What is prevalence of bed bugs?
resurgence
Characteristics of bed bugs?
- no wings
- switch-blade proboscis
- can survive for more than a yr w/o a blood meal
What is this???

Pentastome
What is this?

Pentastome
What is this?

Pentastome
What family does this egg belong to?

Pentastome
What is this a larvae of?

Pentastome
What is this a nymph of?

Pentastome
Characteristics of Pentastome?
- Tongue Worm
- Parasites have one mouth & 4 hooked claws
- Zoonotic
- Humans are accidental hosts & can get infected by ingesting undercooked meat w/ nymphal stages
A client brings you his pet snake & dog. Both animals show respiratory signs. What should be on your DDX for parasites?
- Mite pneumonsoides
- Pentastome
What type of LC does Pentastome have?
Indirect LC
What Pentastome is found in the nasal/paranasal sinuses of dogs & cats?
Linguatula serrata
What is this?

Pthirus pubis
General characteristics of Hard Ticks.
- mouthparts
- bodies
- Females’ scutum ONLY covers the anterior part of the dorsum (just behind capitulum
- Males don’t get as large b/c scutum covers entire dorsum
A client calls you out to her farm b/c her horse is acting weird. When you get there, you notice the horse has muscle fasciculations & sweating. What should you supsect?
Otobius
Check horse’s ear for larval or 2 nymphal stages
What is the common name for Ixodes?

“Black-legged” deer tick
Characteristics of Ixodes?
- ANAL GROOVE
- Inornate
- No festoons (butt ridges)

Which 2 hard ticks are ornate w/ festoons?
- Dermacenter
- Amblyomma
Which tick borne disease can be transmitted sexually?
Lyme Dz caused by Borrelia burgdorferi
How are the following diseases of Ixodes transmitted?
- Borrelia burgdorferi = Interstadial
- Anaplasma = Interstadial
- Babesia = Transovarian (except Babesia equii)
The Powassan Virus is transmitted to humans via what tick vector? (2)
- Ixodes*
- Dermacentor*
Why is Powassan Virus such a big concern?
Majority of people infected w/ this virus die rapidly
What can you expect to happen if a mare is infected w/ Babesia?
Abortion
Why are Babesia bovis & B. bigemina such a problem?
Out of control b/c have adapted their life cycle to wild ruminants (white tail deer)
Characteristics of Dermacentor?
- Ornate
- Festoons
- Short to medium palps

Ticks that cause “tick paralysis”
- Ixodes
- Dermacentor
- Amblyomma
Which 2 ticks can transmit Powassan Virus?
- Ixodes
- Dermacentor
What can Dermacentor transmit?
- POWV
- RMSF
- Tick paralysis
- Cytauxzoon felis
- Tularemia
- Anaplasma marginale
- Q fever
Which protozoa causes fatal disease in cats (w/in 48 hrs)?
Cytauxzoon felis
(come in dead & you see piroplasts)
What are the target cells of C. felis? What C.Ss do they cause?
- Macrophages - Vasculitis
- RBCs - Hemolytic anemia
Reservoir for C. felis?
bobcats
Owner brings you in their dead dog. You see piroplasts, macrophages full of protozoan, & hemorrhage? What is it?
Hepatozoon americanum
What tick in Grenada is implicated in the transmission of Ehrlichia?
Rhipicephalus

How does Boophilus transmit Babesia to cattle? What other animal does it like?
- Transovarian
- White Tailed deer
Characteristics of Amblyomma?

- ornate
- festoons
- mouthparts are longer than the basis capituli
- PAINFUL BITE
Which hard tick is reportable?
Boophilus

Why can you not import wild African Leopard Tortoises?

B/c they can harbor Amblyomma larvae and nypmhs which can transmit Ehrlichia ruminatum (Heartwater Dz)
Dog comes in with periosteal proliferation. What’s the next step? DDX?
Biopsy
Hepatozoon americanum transmitted by Amblyomma
If a person has a red meat allergy what tick were they likely bitten by?
Amblyomma
(allergen has been identified as a carbohydrate called Alpha-Galactose, commonly known as alpha gal.)
Which species of Amblyomma is this? (Lone star Tick)

Amblyomma americanum
Which species of Amblyomma is this?

Amblyomma maculatum
What is the prognosis of a dog infected with Hepatozoon americanum?
Guarded b/c more severe
How do dogs get Hepatozoon?
Ingest an Amblyomma tick containing sporulated oocysts of Hepatozoon.
Characteristics of Soft Ticks
- mouthparts not visible from dorsal view
- lack a dorsal shield or scutum
- hard to tell sexes apart unless engorged
- Skin = leathery, wrinkled, granulated, mammillated or covered w/ bumps/spines (EXCEPT LARVAE)
What is the common name for Argas?
Fowl tick
You find Argas on your young chickens. What C.S. will you also suspect to see?

flaccid paralysis
What is the common name of Otobius?
Spine nose ear tick
Which Soft Tick is rarely zoonotic?
Otobius
Does adult Otobius feed?
No way jose
Characteristics of Mesostigmata (mites)
- blood sucking mites of birds, rodents & reptiles
- legs confined to anterior ½ of body
- stigmata is between 3rd & 4th coxae
- Peritreme
- Chelicerae (piercing mouthparts)
- Berlese technique
- -ZOONOTIC if definitive host is not around
What is the blood sucking mite of reptiles?

Ophionyssus
BEWARE could be ZOONOTIC
How would you DX Ophionyssus in snakes?
- put snake bedding in Berlese Funnel
- snake not properly shedding its skin
What is the blood sucking nasal & paranasal respiratory mite of dogs?

Pneumonyssoides
What is the C.S. seen in dogs w/ Pneumonyssoides?
- sneezing
- epistasis
- coughing
Characteristics of Pneumonyssoides.
- Ovoviviparous (Larvae in egg) females
- No nymphal stage
- Transmission: direct transfer of 6 legged larvae from dog to dog
How can you DX Pneumonyssoides?
- rhinoscopy
- nasal swabbing
- nasal flushing of sinuses
In what large animal is Sarcoptes not reportable?
Swine
(oink, oink)
Characteristics of Sarcoptes.
- big & round
- long stalk
- no segmentation
- burrow deep into skin

My guinea pig is flipping out!!! What could it be doc?
(PE= seizures from scratching skin, self trauma, hyperkeratosis, alopecia, & intense pruritis)
Trixacarus mite
What is the rare form of mange w/ lots of hair loss but no pruritis affects seen in immunocompromised dogs?
Norweign scabies
What causes Scaley leg in chickens, canaries, turkeys & pheasants?
Knemidokoptes
Where will you find Knemidokoptes?
burrowing in the epidermis around legs, beak, back & vent
Which animals are Psoeptes reporatble in?
Large animals
Characteristics of Psoroptes?
- Don’t burrow
- intense pruritis with scabs & crusting
- long 3 segmented pedicles
- “Scab mite”
- External ear canal of rabbits
- Rhasta sheep
A hedgehog comes in & has lost all its quills. What do you suspect?
Chorioptes
Characteristics of Chorioptes
- don’t burrow
- short, unsegmented pedicles
- cause hair loss on back, mane, fetlock & tail head
Dog, cat, kitten, puppy, fox or ferret comes in w/ black stuff in their ear. See a mite w/ short stalk & caruncles. What is it?
Otodectes
What is Cheyletiella?
causative agent of “walking dandruff” (scaling & mild pruritis)
What are the hosts of Cheyletiella?
Dogs, cats, rabbits & humans
ZOONOTIC
Highly contangious
What is unquie about Demodex infections?
very host specific, every mammal has its own kind
How does Demodex present in large animals?
large nodules
must lance & examine debris to DX
What is the common name for Demodex?
Red Mange
When can Demodex be severe?
if have sqaumous or pustule form
What is a common way that Demodex is transmitted in dogs?
Common transmission from dam to pup during sucking from skin not milk signs <7mths
Characteristics of Chiggers
- Hosts: dogs, cats, rabbits, all large animals & man
- Parasitic larvae (nymphs & adults non parasitic)
- Immonogenic saliva
- Zoonotic
Puppy comes in w/ localized hair loss that becomes generalized what does this indicate?
T-cell autosommal recessive issue (compromised immune system)
Demodex is normal flora
Going to be difficult to control b/c of immune issues
What can cause adult onset of Demodex?
Estrus or other immunocompromissing events
What life stages of Chiggers are parastitic?

Just larvae