Sheep Blowfly, Nasal bot and Ticks

Question 1

What is myiasis?

Answer 1

The infestation of the organs and tissues of living animals by the larvae of dipteran flies

Question 2

Which species are obligate myiasis and name the flies?

Answer 2

Family- Oestridae 
Flies- 
Hypoderma spp- cattle
Gasterophilus spp- horses
Oestrus ovis- sheep

Question 3

Which family are facultative myiasis?

Answer 3

Calliphoridae

Question 4

What is the common name for myiasis?

Answer 4

Blow fly or blowfly strike

Question 5

What fly is the primary blowfly and how can the adult and larvae be ID?

Answer 5

Lucilia sericita
Adult ID- 1cm, green metallic, dorsal bristles
Larvae- Smooth, segmented, L1- 1mm, L3- 10-14mm, anterior oral hooks, posterior spiracles

Question 6

What is an example of a secondary myiasis species?

Answer 6

Callophora vicina (blue bottle)

Question 7

Describe the life cycle of L.sericata

Answer 7

3 phases
Eggs laid on wool
Hatch
L1 wiggle down fibre
Malt to L2
Malt to L3
Drop to floor
Become pupae, adults

Question 8

Describe the pathogenesis and clinical signs of blowfly

Answer 8

Larvae feeding- digest tissue, abrade tissue
Lesions odour, bacterial infection
Secondary blowflies attracted 
Clinical signs
Nibbling
Anorexia
Loss of condition
Dull
Isolated
Increase in body temp

Question 9

What sheep body sites are at risk of blow fly?

Answer 9

Breech- scouring
Body
Tail- scouring
Poll- rams from fighting
Penile shaft
Foot (foot rot)

Question 10

What are some environmental and host risk factors of blowfly strike?

Answer 10

Host- wool length, scouring, skin folds, tail length, wounds

Environmental- warm weather, summer rain, abundance of flies, breeding sites

Question 11

How is blowfly treated?

Answer 11

Separate sheep
Clip wool around lesion
Remove larvae
Dress wound with insecticide

Question 12

How is blowfly controlled?

Answer 12

OP dips (diazinon)
SP pour on preparations (cypermethrin)
Insect growth regulators
Shearing, docking tails, dagging/crutching, GI nematode and coccidia control, wound treatments, foot rot management, carcass disposal

Question 13

How is blow fly strike in rabbits prevented and managed?

Answer 13

Prevention- cyromazine- 10 weeks, permethrin 2 weeks

Integrated management- hygiene and space, clipping

Question 14

What is the common name for oestrus ovis?

Answer 14

Sheep nasal bot

Question 15

What is the family of oestrus ovis, how long is its life cycle?

Answer 15

Oestridae
1 year life cycle
Obligate parasite

Question 16

Describe the life cycle of oestrus ovis?

Answer 16

L1 squirted into nose by adult female
L1 moults to L2 in nasal pasage
L2 moult to L3 in frontal sinuses
Mature L3 move to nostrils
Sneezed out
Pupate in soil
Adult fly 3-8 weeks later

Question 17

How is oestrus ovis diagnosed and controlled?

Answer 17

Diagnosed based on clinical signs

Control- ivermectin, moxidectin

Question 18

What three diseases can sheep get from ticks?

Answer 18

Anaplasma phagoctophilium
Louping ill virus
Tick pyaemia