Cattle Flies

Question 1

What family do cattle flies belong in?

Answer 1

Oestridae

Question 2

What is the common name for the hypoderma spp of flies and what two species infest cattle?

Answer 2

Common name- Warble flies

2 species- hypoderma bovis and hypoderma lineatum

Question 3

What is the appearance of the warble fly and when are they most active?

Answer 3

Appearance- bee-like

Active June- Sep in UK on warm days >18

Question 4

How can hypoderma bovis and lineatum eggs be distinguished?

Answer 4

Hypoderma bovis lays eggs individually lineatum lay several in a row

Question 5

Describe the life cycle of the hypoderma species

Answer 5

Eggs laid usually on legs
Hatch and migrate through connective tissue
H.Bovis toward epidural fat along spinal canal
H.Lineatum toward submucosa of oesophagus
Moult to L2 at the sites and migrate to dorsal connective tissue (jan/feb)
Moult to L3 grow and become ‘warble’
Emerge through skin drop to ground pupate to adult fly

Question 6

When do the two species of hypoderma when do they emerge?

Answer 6

H.Lineatum March/May

H.Bovis May/June

Question 7

What problems do warble flies cause?

Answer 7

Gadding cows
Perforation of hide- breathing holes
Butchers jelly

Question 8

How can warble flies be diagnosed treated and controlled?

Answer 8

Warbles are readily palpated- ELISA available
Ectoparasiticides- inject Ivermectin
Control- was notifiable, eradication programme, ELISA monitors prevalence

Question 9

What biting muscidae pester cattle?

Answer 9

Stomoxys calcitrans- stable fly
Iyperodia irritans- horn fly
Glossina spp
Trypanosoma spp

Question 10

Which non biting muscidae pester cattle?

Answer 10

Hydrotea irritans
Musca autumnalis
Musca domestica

Question 11

What are the resting sites, feeding sites, host responses, feeding frequency and potential transmission of pathogens of stomoxy calcitrans (stable fly)?

Answer 11

Resting sites- fence posts
Feeding sites- enclosed environment (stables)
Host response- gadding
Feeding frequency- frequent feeders
Vector transmission- west nile
Breed in dung mixed with straw and urine

Question 12

What problems do stomoxys calcitrans cause in cattle?

Answer 12

Loss of blood
Loss of weight gain
Milk production drops 40%
Nuisance

Question 13

Describe the appearance of lyperosia irritans (horn fly) and is it non-biting or biting?

Answer 13

Small fly with biting proboscis
Found on back of only cows
Biting

Question 14

Where are lyperosia irritans found, where do they lay eggs and what disease can they cause?

Answer 14

Found on pasture
Lay eggs in fresh dung
Can cause anaemia

Question 15

What is the common name for glossina spp and describe the appearance of the fly?

Answer 15

Tsetse fly 
Both sexes require large frequent blood meals
Yellow/dark brown
6-14mm
Wings held like scissor blades

Question 16

How does the tsetse fly produce young?

Answer 16

One egg produced at a time ‘inside mum’
Larva nourished by fluids from milk glands
Female repeatedly feeds on blood for larvae support
Full grown larva deposited on soil just prior to pupation

Question 17

What diseases does glossina spp cause?

Answer 17

Transmits T.congolense and other trypanosomes
Nagana in cattle
African sleeping sickness in humans

Question 18

What does trypanosomes cause?

Answer 18

Lymphoid enlargement/splenomegaly
Anaemia- a major feature
Lethargy, fever
Chronic and fatal if untreated

Question 19

How is tsetse fly being controlled in sub-shara Africa?

Answer 19

Aerial spraying
Stetile insect technique 
Fly traps
Trypanocidal drug treatment
Breeding trypanotolerant livestock

Question 20

What trypanosomes are transmitted in the UK and by what species of fly?

Answer 20

Trypanosome theileri is transmitted to cattle by tabanids

Question 21

How can hyrotaea irritans (head fly) be distinguished?

Answer 21

Orange wing base greenish abdomen

Question 22

What problems do hydrotaea irritans cause, where do they deposit eggs and how many generations are there a year?

Answer 22

Problems- Pests, Cause summer mastitis- mechanical transmission from several bacteria
Deposit eggs on pasture soil- one generation

Question 23

Whats the common name of musca autumnalis?

Answer 23

The face fly

Question 24

Describe the appearance of the face fly

Answer 24

Brown grey, housefly-like

Spongy proboscis

Question 25

What disease does musca autmumnalis cause?

Answer 25

Pink eye- infectious bovine keratoconjunctivits due to mortadella bovis

Question 26

How are flies controlled in the UK?

Answer 26

Use of synthetic pyrethroids on cattle- sprays, pour ons, ear tags
Treat at turn out
Treat surfaces
Barrier- tape on teats
Good husbandry, dung removal delays/reduces build up stomoxys

Question 27

What is Mallophaga and Anoplura?

Answer 27

Mallophaga- contains biting/chewing lice

Anoplura- contain the sucking lice

Question 28

What family of lice are not found on birds

Answer 28

Anoplura

Question 29

How long does a lice egg to adult cycle take?

Answer 29

3-4 weeks

Question 30

What are the 4 lice of cattle and where are they found?

Answer 30

Haematopinus eurysternus- poll, horn base, eyes nostrils
Linognathus vituli- head, neck, dewlap
Solenopotes- head, neck, dewlap
Bovicula/damalinia- forehead, shoulders, back and rump

Question 31

Which cattle lice are sucking and biting?

Answer 31

Sucking- haematopinus, linognathus, solenoptes

Biting- Bovicula

Question 32

What reasons are cattle particularly affected?

Answer 32

Temperate regions, housed cattle with thick coats

Question 33

What do heavy lice infestations cause?

Answer 33

Intense irritation, rubbing, hair loss, hide damage, anaemia, weakness

Question 34

How are cattle lice controlled?

Answer 34

Synthetic pyrethroids pour ons effective against both lice
ML- avermectin/milbemycin pour-ons
Second treatment may be needed 3-4 weeks later
Never under dose
Treat all cattle- or isolate