< Back to Quick Quiz Listing

The quiz questions are taken from:

The online learning pages focus on the important topics within worms, flies and lice and offer two approaches to learning: structured reading and question and answer.

We also welcome suggested questions for the quiz, (either reply on the ParaBoss News email if you are subscribed or use Contact Us, at the bottom of the web page).

Answers and links to further information are provided below the image.

Questions

1. What weather conditions would indicate that Nematodirus (the thin-necked intestinal worm) could be a cause of scouring in young stock?

2.  Would you give a routine pre-kidding drench to does in the WormBoss East Coast Zone if kidding is to be spread out over many months?

3. ‘Shear and treat immediately’ is just one option to control lice on ‘introductions’. This option gives good biosecurity, but it may result in high chemical residues. Name 3 situations when it is the best option.

4.  Name two non-chemical flystrike control strategies and describe why they delay the development of insecticide resistance in flies?


 ‘Shear and treat immediately’ is just one option to control lice on ‘introductions’. Image: Viper Pour-on, courtesy Bayer Animal Health.
‘Shear and treat immediately’ is just one option to control lice on ‘introductions’. Image: Viper Pour-on, courtesy Bayer Animal Health.

Answers

1. What weather conditions would indicate that Nematodirus (the thin-necked intestinal worm) could be a cause of scouring in young stock?

Nematodirus is usually present in cooler-inland dry climates.

The typical series of events that produce outbreaks of Nematodirus infections are a period of dry, followed by reasonable rains that produce short, green feed. Serious problems tend to be seen in young sheep grazing close to the ground.

Immature worms damage the small intestinal wall during feeding and can cause severe productivity losses in young stock well before any worms have had time to develop into adults. 

The larvae of Nematodirus, unlike most other gastro-intestinal nematodes, retain their eggshell after hatching and this extra layer of wrapping acts as an insulator against hostile dry weather conditions enabling them to better survive when other worm larvae would die.

2.  Would you give a routine pre-kidding drench to does in the WormBoss East Coast Zone if kidding is to be spread out over many months? 

Yes, when kidding is spread out over many months, and the herd is run as one group, give the routine pre-kidding drench as usual to each individual doe, 4 weeks before kidding.

However, this pre-kidding drench will not be as effective as drenching the doe and moving her to a low worm-risk paddock.

3. ‘Shear and treat immediately’ is just one option to control lice on ‘introductions’. This option gives good biosecurity, but it may result in high chemical residues. Name 3 situations when it is the best option.

  • When the introductions are few, such as purchased rams or strays collected from the neighbour.
  • When the consequence of lice spreading to your existing flock will be more serious than just the cost of fleece damage and treating the flock next shearing. For example, a stud breeder may have a reputation to protect.
  • When the introduced sheep are obviously lousy, and your ability to isolate them from the existing flock is poor.
  • When your sheep have been lice-free for many years, and you want to remove any chance of lice introduction from external sources.

4. Name two non-chemical flystrike control strategies and describe why they delay the development of insecticide resistance in flies?

Non-chemical strategies include (1) genetic selection for flystrike-resistant sheep, (2) timing of shearing and crutching, (3) docking tails to correct length, and (4) breech modification, and are part of an integrated pest management program. These non-chemical strategies reduce reliance on chemicals allowing chemicals to be used less and giving more opportunities for chemicals to be rotated. Insecticides are advised only when necessary.