2016 December

Many of the quiz questions are taken from:

• WormBoss Online Learning
• FlyBoss Online Learning
• LiceBoss Online Learning

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. Why/how does smart grazing work to prepare a low worm-risk paddock for weaners during winter in the winter rainfall regions?

2. Which Insect Growth Regulator (IGR) for flystrike prevention can only be used in a spray-on form?

3. In what situations when introducing sheep might the immediate shearing and treating for lice be the best approach?

4. When treating goats for worms, why are cattle pour-on products not suitable?

Answers

1. Why/how does smart grazing work to prepare a low worm-risk paddock for weaners during winter in the winter rainfall regions?

The intensive grazing periods:

• Reduce the amount of pasture dry matter, making the pasture less suitable for the survival of worm larvae.
• Ensure that there is no deposition of worm eggs on the pasture from the time of the first summer drench until the autumn break.
• Allow the drenched sheep to 'vacuum' up infective larvae in much the same way as cattle do when they are used in alternate grazing programs with sheep.
• Have the same cumulative stocking pressure from November to March as set-stocked paddocks grazed continuously by wethers.
• Are quite flexible. What must not be changed is the need (i) not to exceed 30 days grazing after each summer drench, and (ii) for a fully-effective product to be used at the summer drenches.

2. Which Insect Growth Regulator (IGR) for flystrike prevention can only be used in a spray-on form?

Dicyclanil can only be used as a spray-on.

Cyromazine can be used as a spray-on, for jetting and dipping, and as a flystrike dressing (though it acts slowly).

3. In what situations when introducing sheep might the immediate shearing and treating for lice be the best approach?

This option is the best option for biosecurity, but is rarely cost effective. It best suits these situations:

• When the introductions are few in number, such as purchased rams or strays collected from the neighbour.
• When the consequences of lice spreading to your existing flock are 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 completely remove any chance of lice introduction from external sources.

4. When treating goats for worms, why are cattle pour-on products not suitable?

Cattle pour-on products should not be used for worm control in goats. Pour-ons should never be used as a drench, as the liquid in which the active ingredient is dissolved is very toxic to the lining of the gut.

Goats have much less subcutaneous fat than sheep and cattle and this can affect the absorption of pour-on products, which must be applied along the back and then absorbed.