Online learning—Susceptibility

This section describes flies, where they strike and under what conditions. 

Structured reading

For those who like to see all the information and simply read through it in order. Each heading is a link to a page of information—the dot point provides a summary of the page.

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Susceptibility
Factors that determine the susceptibility of sheep to flystrike.

Breech strike
Issues associated with breech strike.

Body strike
Issues associated with body strike.

Other types of strike
Strike, other than breech and body strike.

Blowfly biology
About flies, including their lifecycle.

Blowfly identification
NSW DPI information sheet on identifying blowflies.

Seasonal conditions and geography
Conditions and geography under which flies are more active

 

Question and answer

For those who prefer a problem based approach to learning, answer the following questions.
Each of the questions below links further down the page to the answers.

Questions:

  1. What are the two most important factors for susceptibility to breech strike?
  2. What is the most important factor for susceptibility to body strike?
  3. Aside from breech and body strike, what are the other common places sheep get struck?
  4. Which fly initiates most strikes in Australia?
  5. Under what conditions will flies strike sheep?
  6. Are there particular paddocks or areas where flystrike occurs more often?

Answers:

You can also click on each question below to go to FlyBoss pages with related information.

1. What are the two most important factors for susceptibility to breech strike?

Research over many years has shown that the two most important factors affecting breech strike risk are breech wrinkle and dag.

2. What is the most important factor for susceptibility to body strike?

Research over many years has shown that the most important factor affecting the risk of body strike is the presence of fleece rot.

3. Aside from breech and body strike, what are the other common places sheep get struck?

  • Poll or head
  • Pizzle
  • Wound

4. Which fly initiates most strikes in Australia?

The Australian sheep blowfly, Lucilia cuprina, initiates over 90% of all flystrike in the Australian flock. Other fly species will strike sheep but only in small numbers and do not escalate into fly waves.

5. Under what conditions will flies strike sheep?

Ideal conditions for the blowfly involve warm (17ºC–38ºC), humid weather. They do not like;

  • cool weather (less than 17°C)
  • excessive heat (greater than 38°C)
  • dry climates
  • wind (greater than 30 km per hour)

6. Are there particular paddocks or areas where flystrike occurs more often?

In general, paddocks that are more exposed to wind, with less ground cover, timber and wet spots, will have less flystrike risk , making them more suitable for high risk mobs of sheep, such as marked lambs, daggy sheep and lambing ewes.

 


Links to the other FlyBoss online learning topics

  1. Susceptibility (you are currently on this page)
  2. Breeding and selection
  3. Management
  4. Treatment
  5. FlyBoss Tools