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Flashcards in Arthropods Deck (61)
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What is the most prominent blood sucking dipteran?

Family Culicidae: made up of mosquitoes.


What is the life cycle of culicidae (mosquito)?

1. Eggs
2. Larvae - 1st molt in 5 - 6 days (3x total); they are filter feeders
3. Pupae - stage that lasts 2 - 3 days; non-feeding
4. Adults - lifespan 6 - 7 days; they mate once


What are the sufamilies within the culicidae family?

Anopheline: anopheles sp.
Culicine: aedes sp.
Culicine: culex sp.


What diseases are the anophelines vectors for?

Intermediate host/vector for plasmodium spp.


What diseases are the culicines vectors for?

Yellow fever, fengue fever, west nile encephalitis


How do you control for the culicidae family?

Control by implementing:
- larvivorous fish (guppies)
- 'beneficial' mosquito larvae - that feed on other mosquitoes
- sticky mustard seeds - prevent larvae from eating
- draining breeding sites


Facultative myiasis
Where do they deposit their eggs?
What can it cause?

- normally eggs are deposited in feces, rotten carrion, garbage
- occassionally they are deposited in contaminated wounds

It can cause dermatitis, numerous maggots, pungent odor, inflammation


Facultative myiasis:
What species are examples of this process?
Who are their hosts?
What type of feeders are they?

Blow flies/bottle flies
- hosts: Any mammal
- vomit-drop feeders


Obligatory myiasis
1. define
2. What is the main difference between facultative and obligatory myiasis

1. Larve MUST use animal host to complete its life cycle by laying its larvae in living tissue, uncontaminated wounds, soft tissue.

2. Obligatory myiasis must ingest LIVING tissue in order to complete their lifecycle.


Cochliomyia hominivorax
- what form of myiasis do they use?
- common name?
- are they reportable?
- who are their hosts?

- obligatory myiasis
- "primary screwworm"
- eradicated by sterile male release in US and central america
- they are reportable!!
- they affect any mammal; first fly on the scene with fresh, living tissue


Cochliomyia hominivorax
- pathogenesis
- diagnosis
- treatment

- pathogenesis: toxemia, bacterial infection, death
- diagnosis: larval ID, dermatitis, pungent odor
- treatment: remove larvae, treat secondary bacterial/fungal infections


Cuterebra spp.
- what type of myiasis do they use?
- what is their common name?
- hosts?
- what is important about adults?

- they use obligatory myiasis
- "wolves" , "warbles"
- hosts: cats, dogs, rabbits, rodents
- adults are non-parasitic


Cuterebra spp.

1. Eggs deposited near entrance to burrow/nest
2. They enter host
3. Migrate thru host
4. Subcutaneous cysts produced (sometimes nasal or oval)


Cuterebra spp.
- pathogenesis
- diagnosis
- treatment

- cysts, swellings - secondary infections
- heals slowly
- larval migrations

- larval ID

- surgically remove larvae; dont break them it will cause anaphylaxis
- no approved treatment
- ivermectin, milbemycin, selamectin may kill larvae


Class insecta: orders anoplura & mallophaga
What parasite is part of this order?
What disease process do they cause?
What is it's veterinary importance?

- lice!
- causes pediculiasis: infestation of lice
- veterinary importance: irritation to host, severe infestation can cause anemia, disease vectors, social stigma


Anoplura and mallphaga: lice

1. Females produce 1 egg (nit) at a time that is cemented to hair shaft or feather
2. Egg (nit) hatches 1 - 3 weeks - 3 nymphal stages
3. Adults within 4.5 weeks
4. They are a permanent ectoparasite and are stenoxenous (very host specific)


What is the difference (and names) of the two lice groups?

- chewing lice feeds on skin cells
- their head is wider than their thorax

- blood feeders
- head is narrower than thorax


- who is their host?
- name some examples

- mammals only

Linognathus setosus (dog)
Pediculus humanus humanus (body)
Pediculus humanus capitis (head)
Pthirus pubis (pubic)


Treatment of anoplura & mallophagia

Carbaryl shampoos, sprays, dips


Class insecta: order siphonaptera
- what parasite is part of this group?
- what do they cause?

They cause siphonapteriasis: infestation with fleas


1. Name a common flea found on dogs and cats
2. What flea carries bubonic plague?
3. What flea is found in poultry, dogs, cats, and humans and is also known as the stick-tight flea?

1. Ctenocephalides felis
2. Xenopsylla cheopis
3. Echidnophaga gallinacean


Where are most stages of the host found?

Off the host


1. Where are flea eggs laid?
2. When do they hatch?
3. How many eggs does a female flea lay?

1. Laid on host, quickly fall off
2. They hatch in 2 - 16 days
3. Females > 500 eggs


Flea larvae
1. How long is the larval stage?
2. How many molts?
3. What are they covered with?
4. What do they feed on?
5. What are they susceptible to?

1. 7 - 10 days
2. 2 molts
3. Covered in setae
4. Feed on "frass"
5. Susceptible to heat and desiccation


Flea pupae
- how long is this stage?
- what makes this stage tricky to control?

- this stage can be completed in 4 days
- what makes this stage tricky is that emergence of adults can be prolonged up to 174 days depending on environmental conditions


Flea adults
- how often do they mate?
- when do they feed after getting on host?

- they mate once
- they begin feeding


Flea allergy dermatitis
- definition
- what is severity related to?
- at what age does this disease onset in hosts?

Defined: biting fleas that introduce salivary proteins (antigens).

Severity is related to duration of feeding and amount of salivary protein introduced

3 - 5 years of age


Flea allergy dermatitis
- geography of lesions: where are they most commonly found
- what are the characteristics of these lesions?

- lumbo-sacral region, caudal thighs, proximal tail, ventral abomen

- characteristics of lesions: papules, crusts, alopecia, excoriations, erythema, hyperpigmentation.


Flea control
Combination of what?

Combo of chemical and mechanical means which target both the animal and its envionrment


What do host-targeted flea controls consist of? (2 types)

1. Insect growth regulators (IGRs)
2. Insect development inhibitors (IDIs)