Closely examine for signs of worms, yard or hold sheep against a fence. Catch and examine 5—10 animals.
Barber's pole worm: anaemia (pale inside eyelids and gums); 'bottle jaw' (swelling under the jaw); lagging or collapse when mustered; death.
Scour worms (black scour worm [Trichostrongylus species]; brown stomach worm [Teladorsagia circumcincta]; and others [incl. Nematodirus]): dark scours; weight loss; death.
NOTE: Other diseases can cause similar signs. Consider getting animal health advice.
NOTE: If treatment was less than 3 weeks ago and you now have a positive result, your drench may be ineffective. Seek professional advice because a DrenchTest might be required.
In the table below, find the worm egg count threshold for the average sheep condition of your mob and the condition of the pasture they will graze.
(If pasture[1] or sheep condition[2] is unknown, use a worm egg count value of 1000).
| Worm egg count (epg) thresholds for barber's pole worm | |||
| Sheep condition[2] (or growth rate for weaners) | Pasture condition[1] | ||
| Poor | Moderate | Good | |
| Poor | 600 | 800 | 1000 |
| Moderate | 800 | 1000 | 1100 |
| Good | 1000 | 1100 | 1200 |
In the table below, find the worm egg count threshold for the average sheep condition of your mob and the condition of the pasture they will graze.
(If pasture[1] or sheep condition[2] is unknown, use a worm egg count value of 500).
| Worm egg count (epg) thresholds for scour worm | |||
| Sheep condition[2] (or growth rate for weaners) | Pasture condition[1] | ||
| Poor | Moderate | Good | |
| Poor | 300 | 400 | 500 |
| Moderate | 400 | 500 | 600 |
| Good | 500 | 600 | 700 |
Region: Qld/NSW Summer Rainfall / Tablelands and Slopes
Date: %18 %Nov %2024
Treat lambing ewes with an effective short-acting drench[1] and then WormTest 1 week before lamb marking. In a well-prepared low worm-risk paddock, ewes often do not need treatment at lamb marking.
NOTE: While mid-length (some combined with vaccine) and long-acting 'mectin'/ML (macrocyclic lactone) products provide convenience, their use in this situation can increase drench resistance on your farm. It is best to reserve these treatments for the higher and longer worm-risk times later in summer and autumn. They are not required when low worm-risk paddocks are used.
Treat lambing ewes with an effective short-acting drench[1]. A WormTest 1 week before lamb marking is essential.
Consider preparing a low worm-risk lambing paddock from autumn next year.
NOTE: While mid-length (some combined with vaccine) and long-acting 'mectin'/ML (macrocyclic lactone) products provide convenience, their use in this situation can increase drench resistance on your farm. It is best to reserve these treatments for the higher and longer worm-risk times later in summer and autumn. They are not required when low worm-risk paddocks are used.
Treat weaners with an effective short-acting drench[1] and then WormTest 4 weeks later[2].
NOTE: While mid-length (some combined with vaccine) and long-acting 'mectin'/ML (macrocyclic lactone) products provide convenience, their use in this situation can increase drench resistance on your farm. It is best to reserve these treatments for the higher and longer worm-risk times later in summer and autumn. They are not required when low worm-risk paddocks are used.
Treat weaners with an effective short-acting drench[1] and then WormTest 4 weeks later[2].
However, a long-acting treatment may be warranted at weaning because low worm-risk weaning paddocks were not prepared and if the next few months are predicted to be high worm-risk weather conditions. Follow the guidelines below for long-acting drenches[1].
Treat the entire mob now with a drench[1] shown to be effective against the worms present and then WormTest 4 weeks later[2].
NOTE: Do not use an organophosphate drench on severely worm-affected or stressed sheep. Consider that other parasites/diseases cause similar signs.
Treat affected individuals now with an effective short-acting drench[1] and WormTest the mob now. Also, investigate other causes of their signs.
NOTE: Do not use an organophosphate drench on severely worm-affected or stressed sheep.
WormTest now, then return to this Drench Decision Guide to see if the worm egg count indicates the need for drenching.
Anytime that you are concerned that the treatment is not providing protection, WormTest immediately.
WormTest in 4 weeks (summer) or 6 weeks (winter) after the last treatment was given and observe sheep closely for signs of worms[1].
WormTest in another 4 weeks (summer) or 6 weeks (winter) and observe sheep closely for signs of worms[1].
This recommendation should be read with the information provided below.
Review available drenches with the WormBoss drench search
Closely examine for signs of worms, yard or hold sheep against a fence. Catch and examine 5—10 animals.
Barber's pole worm: anaemia (pale inside eyelids and gums); 'bottle jaw' (swelling under the jaw); lagging or collapse when mustered; death.
Scour worms (black scour worm [Trichostrongylus species]; brown stomach worm [Teladorsagia circumcincta]; and others [incl. Nematodirus]): dark scours; weight loss; death.
NOTE: Other diseases can cause similar signs. Consider getting animal health advice.
Sheep can sometimes be rapidly re-infected with worms, causing illness and death within 2 weeks of a drench. In these situations (i) check at least weekly for visual signs of barber's pole worm; (ii) use the Haemonchus Dipstick Test; and (iii) conduct a DrenchCheck-Day10. To reduce this risk, prepare low worm-risk pastures.
Follow the product labels. Dose to the heaviest sheep in the mob or groups. Calibrate equipment to ensure the right dose is delivered with the right procedures. Do not mix drenches unless the label states they are compatible. Check withholding periods and export slaughter intervals.
Use these 4 principles together, where possible:
For more details read the drench resistance section in the WormBoss Worm Control Program.
WormTest with a culture at 60 and 90 days after treatment.
If WormTest results are 100 epg or above, drench resistance is likely. Drench immediately with an effective short-acting drench with a different active to the long-acting treatment.
Seek professional advice on the further use of this product.
If WormTest results are less than 100 epg, then treat with an exit drench at 100 days (15 weeks) after the long-acting treatment was given (you can delay drenching if this occurs in the cold period, see next column).
Seek professional advice if WormTests are positive at or before 60 days.
These help to slow drench resistance to persistent treatments.
Protection period of persistent treatments
Mid-length: 7—28 days. Long-acting: 91—100 days.
NOTE: The protection period against susceptible black scour worm with a long-acting moxidectin injection is 49 days.
Use a primer before long-acting treatments
Primer drenches (effective short-acting treatments that do not include the active in the long-acting treatment) should be given concurrently with all long-acting treatments.
Use an exit drench after all mid-length and long-acting treatments
Delay the exit drench if the protection from the persistent treatment runs out during the cold period (average daily maximum temperatures are consistently below 18°C) and an egg count indicates drenching is not required. The exit drench can simply then be given as the next drench that is required, but not later than 3 weeks before the end of the cold period, to ensure removal of any drench-resistant worms.
Anytime that you are concerned that the persistent treatment is not providing protection, WormTest immediately and seek professional advice regarding drench resistance.
Drench Decision Guides
Management tools
Grazing management
Nutritional management
Breeding
Host immunity
The Barbervax vaccine program
Drenches
Drench resistance
Tests
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