Parasitic Skin Diseases II Flashcards
What is a simple/ incomplete insect lifecycle?
The nymph emerges from an egg and looks like an adult
It then grows and moults several times before becoming an adult
What are Insect bodies divided into?
Head, Thorax and the abdomen
What is an ‘instar’
The technical name for an insect lifecycle stage that follows a moult
What is a complex/ complete insect life cycle?
The larva emerges from the egg looking different to the adult, it feeds/ moults several times
The outer cuticle then hardens to form pupa and an adult emerges
What is the meaning of fleas being an ‘almost permanent’ parasite ?
Once they become adults they dont survive very long off of the host
What are the two most common types of fleas?
- Ctenocephalides felis or cat flea
- C.canis or dog flea
How does the flea lifecyccle go
Eggs -> Larvae -> Pupae -> Adult
How long do adult fleas live for?
7-10 days
What percentage of the total flea population is made up of adults?
around 5%
What can fleas cause?
- Host itching/ Irritation
- Skin lesions if they bite humans
- Flea saliva can trigger allergic responses
- Can cause Anemia in heavy infestations
How can you diagnose a flea infestation?
- Clinical signs such as itching/ biting
- ‘Flea Dirt’ Brown flecks which appear to melt into the background
What is the meaning of lice being permanent ectoparasites
They spend their entire life cycle on the same animal
What is pedicuolosis?
A lice Infestation
What are the two different types of lice?
- Chewing Lice (Mallophaga)
- Sucking lice (Anoplura)
What are the characteristics of chewing lice?
- Yellow
- Chewing mouthparts
- Rounded head that is broader than the thorax
- they tend to be mobile and easy to remove
What are the characteristics of sucking lice?
- Tend to be either grey or red depending on how much blood they have taken
- Piercing mouthparts
- Pointed head that is narrower than the thorax
- They tend to remain attached to the animal
Where are chewing lice or mallophaga usually found?
- Usually found on mammals or birds
- they eat skin surface debris, skin flakes, scabs, feathers
What are some key features of sucking lice?
- They are only found on mammals
- They have specialised mouthparts for piercing skin and feeding on blood/tissue fluids
- They have larger claws than chewing lice
- They dont really effect dogs or cats
What is another name for lice eggs?
Nits, they are cemented individually onto hairs
What three categories are flies split into?
- Biting flies or blood feeders
- Non-biting or nuisance flies
- Myiasis causing flies
What is another name for horse flies?
Tabanids
What are three key features about the pathogenesis of horse flies?
- Painful bites, that are irritating to the animal
- They violently abrade the skin to create a pool of blood
- They can also transmit a number of pathogens