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Solutions for
Sheep Parasites


Solutions for Sheep Parasites

To prevent significant production losses and death from occurring, sheep should be routinely monitored to assess worm burdens, to establish infection trends, and to assist with the selection of the most effective treatment.

Management decisions

Using the most effective drench
Pasture management to minimise worm burdens
Spell pastures and/or full tillage to reduce worm burdens
Add a grazing cycle to reduce worm burdens in most circumstances

Genetic selection for worm resistant bloodline
Graze younger stock on cleaner pastures (also lambing ewes)
Faecal Egg Counts (FEC) to determine if a drench is required
Larval culture to determine the most appropriate drench

Understanding the mob’s drench resistance status is imperative to ensure a selected drench is effective – the most expensive drench is the ineffective drench.

Sheep Internal Parasites & Best Practice Worm Monitoring

Zoetis Internal Parasite Solutions

Short Acting Highly Effective Combination Drench

Startect Oral Drench


  • With its proactive dual drench technology, it's the first new class of drench to be released in combination to "Protect", "Prolong" and "Progress"

  • It's such a great sheep drench

Contains the newest active ingredient with a unique mode of action (Derquantel) in combination with highly effective ML, Abamectin1
Startect is the first drench in history with Pro-Active Dual Drench Technology: built-in protection against worm resistance2
Proven to be over 99% effective in over 200 Australian farm trials, even killing multi-resistant worms3
14 day Meat WHP & 28 day ESI (Export Slaughter Interval) provides speed to market and trading flexibility1
Delivers a new level of confidence when it comes to drenching and staying a step ahead of resistance

Startect Drench Applicator Instructional Video

Short Acting Drench

Sheepguard SE Oral

Sheepguard SE

A high-quality broad-spectrum drench that controls roundworms, nasal bot and itch mite in sheep
Contains the powerful second-generation ML, Moxidectin

#we recommend you know your moxidectin drench resistance status with a FECRT.

14 day persistent activity against barbers pole and small brown stomach worms
Short 7 day meat WHP and ESI
Effective against benzimidazole/levamisole resistant roundworms and ivermectin resistant roundworms
Added selenium for improved lamb survival, lamb growth and wool production

Long Acting Drench

Sheepguard Long Acting Injection Drench

Sheep Guard

The long-acting injection that controls roundworms, nasal bot and Itchmite in sheep
  • protects against severe challenge by Haemonchus (barber’s pole worm) for up to 4 months
  • use in ewes pre-lambing where extended protection is required
Contains the powerful second-generation ML, Moxidectin
  • we recommend you know your moxidectin drench resistance status with a FECRT
Effective against benzimidazole/levamisole resistant roundworms and ivermectin resistant roundworms

Use long acting drenches responsibly to maximise their longevity of efficacy
  • use an effective ‘primer’ drench
  • FEC during period of protection
  • use an effective ‘tail cutter’ short acting drench

Best Practice Use of Long Acting (LA) Injection Drench

Conditions where LA treatments make sense
No clean paddocks are available i.e. those with minimal worm burdens

With pre-lambing ewes towards the end of pregnancy to avoid handling

    • interventions need to be limited to avoid stress and not closer than 2 weeks to lambing
    • reduced handling will lower the risk of pregnancy toxaemia in late pre-lambing ewes and mis-mothering if lambs are already on the ground
If long-acting drenches are being used, it is vital they are used responsibly.

Note: Capsules play a very similar role to LA drenches and they should also be used responsibly.

Consequences if LA Drenches are not used responsibly
The irresponsible use of LA products may render that class of actives ineffective on that property.  This means that not only the moxidectin in Sheepguard LA will be at risk, but also the other MLs

With a longer protection period expected, an ineffective drench can result in:
    • dead sheep
    • lost productivity
    • no value for money
    • sheep seeding paddocks with resistant worms
Accelerated drench resistance emerging due to sub-lethal levels of the LA active in the sheep


1. Priming drench (given at the same time as the long-acting product):
Use an effective short-acting drench, preferably a combination, which includes an active from a different class (group) to the long-acting product
It clears the sheep of any worms including those that are resistant to the long-acting drench.

Startect® with its new class of active in combination is an effective priming drench.

Startect is the only drench to contain a Spiroindole class (SI) of active in Derquantel making it a good priming partner with LA drenches.

2. Pooled worm egg count tests at the 30, 60 & 90 day mark following the LA treatment:
Testing at these times will give an accurate measure of the efficacy of the program in use
Any eggs indicate the end of the long-acting pay-out period and the need to schedule the tail-cutter drench
Gives greater certainty as to when the treatment is becoming ineffective.

3. Tail-cutter or exit drench is used two weeks after the end of the actual protection period:
Use an effective short-acting treatment, preferably a combination, which is from a different class to the long-acting product
Ideally done 2 weeks after the long-acting protection period expires
Kills larvae that have survived the persistent treatment and developed into breeding adult worms.


Responsible use will result in

Greater productivity, increased sustainability and overall better value-for-money
A longer and more sustainable use of the more fragile single active ML (mectin) drenches
Opportunities to add value by informing and promoting best practice
Being able to continue using LA treatments into the future.

Sheepguard Long Acting Injector Instructional Video


1. Zoetis Data on File
2. Leathwick DM. Modelling the benefits of a new class of anthelmintic in combination. Vet Parasitol 2012; 186: 93–100.
3. Overall efficacy – GM, Zoetis Data on File

Further Reading

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