Parasitology: Arthropods Flashcards
What are the general characteristics of order insecta?
Adults have 6 legs and 3 body segments
What are the 3 body segments of insecta?
Heady, thorax, abdomen
What is the life cycle of insecta?
Metamorphosis
What is a simple or complete metamorphosis?
immature stages look like small adults
What is a complex or complete metamorphosis?
marked differenced in morphology & structure between adults and immature stages
What are the general characteristics of Siphanoptera?
Macroscopic, usually brown
Wingless
Laterally compressed
Complex metamorphosis
What are Siphanoptera?
Fleas
What are the hosts for Ctenophalides felis
Dog, cat, ferrets, but many others
Where is Ctenophalides felis found?
Worldwide
What type of metamorphosis do fleas under go?
Complete
At what stage are fleas parasitic?
Adults only
What are immature stages of fleas called?
larvae
What happens to eggs of fleas once they have been laid?
Fall off of host in to the environment
What are Siphonaptera legs adapted for?
Jumping and running
What do the immature stages of Ctenocephalides felis prefer in an environment?
High humidity and warm temperatures
What are the stages of the Siphonaptera life cycle?
Adult, egg, first stage larva, second stage larvae, third stage larvae, and pupa
How long can adults stay with in the pupa?
up tp 6 months
How long does it take flea eggs to hatch usually?
2 days
How long does it take the larvae to mature into the pupa form?
6 days
Hoe long does it normally take under the right conditions for pupa to hatch into adults?
6 days
Do female Siphonaptera need a blood meal before they can lay eggs?
Yes they need at least one blood meal before they can lay eggs
What is the toughest stage of Ctenocephalides felis?
Pupa and they are not easily killed by pesticides
How big are Ctenocephalides felis larvae and what do they require for nutrients?
2-5 mm and flea feces
How do you diagnose Ctenocephalides felis
Observation of flea dirt, adult fleas on patient, and patient scratching
What is the clinical importance of Ctenocephalides felis?
Cause hypersensitivity reaction to flea allergy dermatitis and can range from pruritus to hair loss, cause hotspots
What is Ctenocephalides felis a vevctor of?
Tapeworms: Diplidium caninum
Acanthocheilonema roconditum
Bartonella henselae: cat scratch fever
Are fleas generally species specific?
No
What is the name of the rodent flea vector of Yersinia pestis?
Echidinophaga gallinacea (rodent fleas or sticktight flea)
What is the name of the rodent flea vector of Yersinia pestis?
Echidinophaga gallinacea (rodent fleas or sticktight flea)
What are the characteristics of Siphonaptera?
Macroscopic, usually brown
Wingless
Laterally compressed
Complex metamorphosis
What are the general characteristics of Phthiraptera?
Small
Wingless
dorso ventrally falttened
White/grey & some are brown
What are Phthiraptera?
Lice
What are the 2 types of Phthiraptera?
Anoplura: Sucking lice in mammals only
Mallophaga: Chewing, biting lice- mammals & birds
Are lice generally species specific?
Yes
Where are Phthiraptera found?
Worldwide
What is the life cycle of Phthiraptera?
Incomplete/simple
What are the stages of Phthiraptera in the life cycle?
egg, 1st nympth, 2nd nymph, a3rd nymph, adult
What happens tp eggs of lice once they have been laid?
stuck in hairs and feathers
What are Phthiraptera legs adapted for?
grasping and walking
At what stage are Phthiraptera parasitic?
all stages
What are the immature stages of Phthiraptera called?
nymph
How are Phthiraptera diagnosed
observation of live or eggs,
predilection sites
Presence of clinical signs
What are the clinical signs of Phthiraptera infestations?
Pruritis
Hair loss/ poor hair coat
& in severe cases anemia, debilitation
What is the clinical importance of Phthiraptera?
infestation not common in healthy animals especially small animals
uncommon in horses but easily introduced & spread
Very common in large animals
Wild birds: common but not seen in pet birds more common in poultry
Wild mammals: commin
What are the forms of transmission for Phthiraptera?
direct contact or fomites and carrier animals
Who are more susceptible to heavy louse burdens?
Stressed animals are more susceptible to heavy louse burdens
What time of year are animals more likely to have lice?
In the winter months because the host is warm and keep slice warm and is a food supply
About how long is the Phthiraptera life cycle?
About 4 weeks
What is the treatment of Phthiraptera?
Physical removal: self grooming, social grooming, other grooming. On the host adults are easy to kill but the eggs are not killed by drugs. Clean potential fomites as possible from the environment
What does the human louse transmit?
Typhus
What are the two lice that humans can have?
Pediculus: head & body louse
Phthirus: pubic louse
What are diptera?
flies
What are the general characteristics of diptera?
adults have 1 pair of membranous wings
complex/complete metamorphosis
most do not have a parasitic stage
Why do we dislike flies so much?
Fly worry
Flie bites, fly bite dermititis
skin damage
disease transmission
Some larvae are obligate prasites while others are facultative
What species are falls under nonbiting flies?
Musca domestic (house fly)
Musca autumnalis (face fly)
What are the general characteristics of musca domestic?
not parasitic
annoyance can interfere with normal behavior
can serve as a mechanical disease vector
eggs often laid in decaying organic material
short generation times
What are the general characteristics of Musca autumnalis?
females eat secretions (especially tears) for protein
eggs laid in fresh manure
primarilly affects ruminants and horses
What are the importance of Musca autumnalis?
Fly worry
irritation of the eye mucosa leading to inflammation & tearing
What does Musca autumnalis transmit?
Moraxella bovis (causes bovine pink eye)
What species fall under biting flies
Haematobia irritans (horn fly)
Stomoxys calcitrans (stable fly)
Familt Tabanidae (horse/deer fly)
Culicidae (mosquitoes)
Stimuliidae (simulium)
Culicoides spp. ( no-see-ums, midges)
Hippoboscidae
What are the general characteristics of Haematobia irritans (horn fly)?
small flies found on dorsum usually unless it is hot then they are on ventrum
Found on cattle mostly and horses some
adults are resident parasites
eggs laid in fresh manure
Complete life cycle in 10-12 days
What are the importance of Haematobia irritans (horn fly)?
Fly worry
fly bite dermatitis
may carry bacterium causing mastitits
What is the most important external parasite of cattle in the U.S.
Haematobia irritans (horn fly)
