Equine mites and lice Flashcards
What class of ectoparasites are mites? What order?
Arachnids
Acarina
What are the two types of mites? Which cause mange?
Non-burrowing
Burrowing
Both cause mange and dermatitis
Describe the morphology of all mites
Cephalothorax
8 legs in adult/nymph
No distinct abdomen
What mites are found in cattle, sheep and goats?
Chorioptes bovis
Psorpotes ovis
What mite is found in dogs?
Sarcoptes scabeii
What is the only mite (we need to know) in horses? Is it burrowing or non-burrowing
Chorioptes bovis
Non-burrowing
What do Chorioptes bovis mites feed on? How is their mouth adapted for this?
Scales/skin
Round mouthpart
In what season does Chorioptes bovis affect horses? What part of the body do they affect?
Winter Lower limbs (particularly feathered animals)
Describe the morphology of Chorioptes bovis
Round head and mouthpart
Thumb print on body
Very short pedicles at front with cup shaped suckers
How log is the life cycle of chorioptes bovis?
3 weeks
What signs do horses show in response to Chorioptes bovis infestation?
Stamping legs
Papules
Crusty lesions
Hair loss
What is used to treat Chorioptes bovis?
No licensed product - fipronil
Apart from fipronil, how can Chorioptes bovis infestation be reduced?
Clip feathers
Clean rugs/clippers
Use antiseptic cream and hibiscrub on scabs
What class and order are lice?
Arachnid Phthiraptera
Lice are obligatory parasites. What does this mean?
Die within days without host
What are the 2 suborders of lice?
Mallophaga - biting/chewing, feed on skin/scales
Anoplura - sucking, feed on blood
Do lice have wings? Describe their morphology
Flat wingless insects
Stout legs
Claws to cling onto fur/feathers/hair
What is the lifespan of of adult lice? How many eggs can they lay during this time?
1 month
Hundreds
How long does it take for a lice nymph to hatch from the egg? What is a louse egg called?
1-2 weeks
Nit
How long is the lifecycle of a louse?
2-3 wks
What is the word for lice infestation? What does it cause?
Pediculosis
Irritation, pruritis, dermatitis, lack of weight gain
What can be used to treat lice in horses?
Synthetic pyrethroids (permethrin, cypermethrin - also used for equine flies)
What are the advantages of SP for treatment of flies and lice? What should you be aware of?
Slowly metabolised and eliminated
Low mammalian toxicity
Dangerous to fish/crustaceans - careful disposal
Toxic to cats!
Give an example of a Mallophaga (chewing) and an Anoplura (sucking) louse found on horses
Mallophaga - Bovicola equi
Anoplura - Haematopinus asini
Describe the morphology of Haematopinus asini
Sucking mouthpart (long) Large mite (5mm) Yellow/brown with dark margins on abdomen - dragon fruit
Describe the morphology of Bovicola equi
Brown/grey
Striped abdomen
Flat head - chewing mouthpart
Where are equine lice most commonly found?
Base of tail and mane (hair
When are equine lice usually seen?
Winter/Spring - thick coats or wearing a rug
Populations diminish as shed Winter coat and more light
What IPM can be done for equine lice management?
Clean rugs and blankets
