Diptera - Culicoides, Simulium, Gasterophilus and control Flashcards
What are the biting midges? How big are they?
Culicoides spp
What are the distinguishing features of culicoides?
Tiny (1-4mm)
Brown/black body
Mottled wings
How do culicoides feed?
Dig holes and feed on free blood
Where do culicoides lay eggs?
Damp areas (marsh land, compost)
How long is the egg to adult life cycle of culicoides?
3 weeks
How many generations of culicoides are there per year?
1-2
But in huge numbers
What do culicoides cause?
Sweet itch (allergic response to them)
Irritation, allergic dermatitis
Self-inflifcted rubbing lesions on withers, mane, tail
What disease are midges vectors of?
Equine arboviruses:
African horse sickness
Blue tongue
Schmallenberg
What is the species of black flies?
Simulium spp
What are the distinguishing features of simulium spp flies?
Small (1-4mm)
Brownish/orange stout body
Humped thorax
Clear wings
Where do simulium spp lay their eggs?
Require running water
Rivers, streams
How long does it take for a generation of simulium to form?
4 weeks
What do simulium spp cause in ducks and geese?
Leucocytozoon (arctic regions)
What is the species of the horse bot fly, in the Oestridae family?
Gasterophilus spp
What type of parasites are Gasterophilus spp? When are they active/
Obligate myiasis parasite
What are the 3 species of Gasterophilus?
G. intestinalis
G. nasalis (around teeth/nasal cavity)
G. haemorrhoidalis (retum)
What are the distinguishing features of Gasterophilus flies and eggs?
Long triangular shaped abdomen
Large barrel shaped eggs with double row of spines
How many generations of Gasterophilus intestinalis are there each year? When are the eggs laid and where?
1 generation
Eggs laid in Summer on inner legs, hock and shoulders
Describe the life cycle of G.intestanlis
Burrow in tongue Moult and exit to pharynx Moult to L2 and cluster in stomach Moult to L3 and remain to dune L3 passed into dung in June
Do Gasterophilus spp have clinical significance?
Surprisingly little - large red larvae in faeces cause alarm to owner s
How is Gasterophilus diagnosed?
Larve in faeces in Spring
Eggs on tips of hairs in Summer
How can Gasterophilus be controlled?
Removal of eggs on tips of hairs
MLs - ivermectin, moxidectin
What type of management is used for fly control?
Integrated pest management - treat accommodation, fly insecticides, habitat and husbandry, barrier methods (stripes!)
What is the main group used as fly insectidcides?
Synthetic pyrethroids (ear tags, spray on, pour on) Essential oils gain popularity
Dung removal in barns can be used to control which species of fly?
Musca domestica
Stomoxys calcitrans
How can Culicoides midges be reduced? (What can be removed)
Compost heap
