Week 2 - Fleas - COMPLETE **** Flashcards
Define Parasite
an organism that obtains nourishment and shelter in or on another organism
Define Ectoparasite
a organism that spends some or all of their lives parasitising and usually live on or burrow into the surface of the hosts skin
How does the Binomial system work to name an organism?
the first part of the name is the genus
the second part of the name is the species
Anatomy: State the 3 main structural parts of an Insect (flea)
head
thorax
abdomen
Anatomy: What is the exoskeleton made from?
- What is its main function?
- What does the exoskeleton limit and how? 2
a polysaccharide called chitin
it is hard to provide protection
it limits the absolute size of the organism because the exoskeleton is the site of internal muscle attachment
so their body would collapse in on itself if the muscles get any bigger
Anatomy: How do insects grow?
they moult their exoskeleton and must grow before the new exoskeleton hardens
Anatomy: How do they obtain oxygen?
- What are the other functions of this structure and how does it do it? 2
through spiracles in the exoskeleton
a filter at the opening keeps dust out
oils repel water
Anatomy: Digestive System
- How do fleas and mosquitos eat?
- How do flies eat?
they have spikily mouthparts to puncture the hosts skin
they have spongey mouthparts and secrete saliva to digest food and then suck it up
State the names of the 2 different insect life cycles
holometabola and hemimetabola
Life Cycle: Which insects have holometabola life cycles?
- Which have Hemimetabola life cycles?
fleas and flies
lice
Life cycle: Describe the holometabola life cycle 4
eggs
larval stages
pupa
adult
Life cycle: Describe the Hemimetabola life cycle 3
egg
nymph stages
adult
State the name for fleas
siphonaptera
State the physical adaptations for a Flea 5
tube-like mouthparts
laterally flattened with hard exoskeleton
wingless
backwards pointing spines and bristles for attachment to host
enlarged hindlimbs for lumping
Fleas: What do Adult males and female eat and why?
- How do they cause disease in the host? 4
blood because they are obligate blood sucking parasites
irritation
allergy
blood loss
spread of infections
Name: Dog flea
ctenocephalides canis
Name: Cat flea
ctenocephalides felis
Name: Hen flea
ceratophyllus gallinae
Name: Rabbit flea
spilopsyllus cuniculi
Flea Lifecycle: How long can the eggs take to hatch?
- How many larval stages of development are there?
- How long does it take to go through all stages of larval development?
- What is the pupa/cocoon made from?
- How long will it remain in the cocoon once fully developed?
1.5-6 days depending on temperature
3
5-11 days
environmental debris
until it senses the appropriate stimuli
Direct Effects: Why can a severe infestation of young or old animals be dangerous? 2
because the adult female cat flea can suck 13.6 micro litres blood per day
so a severe infestation can lead to anaemia
Direct Affects: How can fleas cause irritation?
- What clinical signs would you see?
some substances in flea saliva act as allergens and can cause a severe allergic response
inflammation
pruritus
Direct effects: Flea Allergic Dermatitis
- What is FAD?
- Which animals have the greatest reaction?
- Which animals will have the smallest reaction?
a common hypersensitivity reaction in cats and dogs
sensitised animals who are intermittently exposed to fleas
sensitised animals who are constantly exposed to fleas
Indirect effects: How can fleas have indirect effects on a host?
- Give 3 examples and information about them
by acting as a vector or host for a range of pathogens
myxomatosis in rabbits caused by a poxvirus
cat scratch disease caused by bartonella henselae
feline infectious anaemia caused by mycoplasma haemofelis
Indirect effects: Cat dog and human fleas can act as intermediate hosts for a specific tapeworm, what is it?
dipylidum caninum which is the dog tapeworm
Indirect effects: Explain how fleas can infect hosts with the dog tapeworm 5
tapeworm eggs pass out in the faeces of the vertebrate host
the faeces are consumed by flea larvae
the tapeworm eggs hatch and the tapeworm develops within the fleas body cavity
the tapeworm larvae form an infective cysticercoid in the adult flea
the adult flea is consumed by the vertebrate host during grooming
Control: What is the most effective non-chemical method for controlling fleas?
- what does this involve?
mechanical removal
removing flea eggs, larvae and organic debris by washing blankets, rugs, pet carrier and vacuuming pet sleeping areas
Control: Give 3 examples of adulticide chemicals and explain how each works
- Give 2 examples of environmental chemicals
organophosphates - they overstimulate nicotinic synapses killing and repelling fleas
pyrethroids - they depolarise neurone via sodium channels killing and repelling fleas
fipronil - they interfere with GABA neurotransmission killing but not repelling fleas
organophosphates
pyrethroids
Control: Give examples of products containing these chemical substances? 5
shampoos
sprays
collars
spot-ons
oral medication
Control: Name 2 examples of insect growth regulators
- How does the first one work?
- Why might this be better for the environment?
lufenuron
methoprene
it interferes with chitin synthesis so strops the development of larvae in eggs and their ability to moult later on
it is stored in body fat and taken up by the adult fleas so does not go into the environment
