Ectoparasites of Horses Flashcards
How are equine lice classified?
Class= insecta Order = Phthiraptera Suborders = Mallophaga + Anopleura
What is the difference b/w Mallophaga + Anopleura suborders?
Mallophaga = biting/ chewing lice Anopleura = sucking lice
Describe the morphology of lice
- small wingless insects
- dorsoventrally flattened
- stout legs + claws
- head + mouthpart adapted for feeding
How does the anatomical features differ b/w mallophaga + anopleura suborders
Both = head, antenna, thorax, tibia, claws, abdomen Mallophaga = + paratergal plate Anopleura = + spiracles
Describe the life cycle of equine lice
- Hemimetabolous
- eggs glued on to hair hatch in 1-2wks
- Life cycle = 2-3wks
- 20-200 eggs/female/mth
What is pediculosis?
Infestation of eggs, larvae + adult lice
What can large infestations of lice cause?
irritation, inflammation, pruritis, dermatitis, weight loss
Name 2 species of equine lice
- Haematopinus asini
- Bovicola equi
Describe the seasonality of lice
usually seen in winter- early spring, populations decrease in spring
How can equine lice be controlled?
- permethrin + cypermethrin (doesn’t affect eggs = retreat after 14 days)
- grooming, clipping, washing rugs/ equipment
How are equine flies classified?
Class = insecta Order = diptera
What are species of non-biting flies called?
Muscidae
What are the suborders of biting flies?
Tabanidae, Culicoides, Simulium
What is the suborder of myiasis flies called?
Oestridae
Name the 4 major species of muscidae flies
- Hydrotaea irritans
- Musca autmnalis
- Musca domestica
- Stomoxys calcitrans
Describe the lifecycle of ‘Hydrotaea irritans’
- Holometabolous (complete metamorphosis)
- 1 generation per yr
- eggs/ larvae/ pupae in soil
- adults usually seen in summer
Which features make Hydrotaea irritans distinguishable?
olive green abdomen w/ orange wing base
What are the risk factors associated with H. irritans?
- exophilic- don’t like buildings
- wooded pasture
- adults most active on warm, overcast, humid days
Describe the life cycle of M. autumnalis
- holometabolous
- multiple generations per yr
- eggs/ larvae/ pupae in dung
What are the risk factors associated with M. autumnalis infestation?
Exophilic, dung on pasture, population build up- most abundant late autumn
What conditions do M. autumnalis acts as vectors for?
- IBK in cattle (infectious bovine keratoconjuctivitis)- similar eye problem in horses
- eye worm- cattle + horses
How does stomoxys calcitrans differ from other muscidae flies?
they are blood sucking- have a large, piercing proboscis
Describe the life cycle of stomoxys calcitrans?
- multiple generations per yr
- eggs/ larvae/ pupae inside liveries/ barns/ stable in soiled bedding
- rest on warm surfaces
What risk factors are associated with stomoxys calcitrans?
soiled bedding, populations build up- most abundant late autumn
