WormBoss worm control program

South Australian winter rainfall

Program Summary

The WormBoss worm control program for the South Australian winter rainfall region has five components that are most effective when used in combination.

A summary of the components is below (click on the headings below for more information):

1. Use grazing management to create low worm-risk paddocks

• Prepare weaning and hogget paddocks using rotational grazing with sheep; a non-sheep use in at least the 6–8 weeks prior to introducing weaners or hoggets (grazing paddocks with cattle, cropping, haymaking, new pasture establishment); grazing with adult sheep that have a tested low worm egg count (less than 50 epg); or grazing with sheep only in the 30 days after they have received an effective drench.
• Choose the least contaminated lambing paddocks for the most susceptible lambing ewes (maidens, oldest ewes and earlier lambing ewes).

2. Breed and feed for worm-resistant sheep

• Use rams with better than average worm egg count (WEC ASBVs¹) and, if applicable to your area, less dagginess (DAG ASBVs); choose the more negative values for both.
• Maintain good nutrition to enhance the sheep’s immunity to worms.

3. WormTest at recommended times

South-East

• Lambs 4–weekly from 12 weeks to turnoff if they are still on their mothers.
• Weaners 4 weeks post-weaning then 4–6 weekly until the end of their second (hogget) winter.
• Ewes pre-lambing, pre-marking and pre-weaning/6–8 wks after marking if weaning is at turnoff.
• Ewes 6–8 weeks after the ‘summer drench’ then 8–weekly until pre-lambing.

Higher Rainfall Mediterranean

• Lambs 4–weekly from 12 weeks to turnoff if they are still on their mothers.
• Weaners 4 weeks post-weaning then 4–6 weekly until the end of their second (hogget) winter.
• Ewes pre-lambing, pre-marking and pre-weaning/6–8 wks after marking if weaning is at turnoff.
• Ewes 8–weekly from when the feed is drying off until pre-lambing.

Lower Rainfall Mediterranean

• Lambs just before weaning.
• Weaners 6 weeks post-weaning then 6-weekly on green pasture, 8-weekly on dry pasture or 10-weekly on crop stubbles until the end of their second (hogget) winter.
• Ewes pre-lambing.
• Ewes pre-weaning only if more than 10% of ewes are scouring.
• Ewes just before harvest then in a further 10 weeks (on pastures) or when they come off stubble.

And at other non-routine times as described in the Drench Decision Guide.

4. Drench² at recommended times:

• Lambs at weaning (only South-East and Higher Rainfall Mediterranean zones).
• Working rams pre-joining.
• The ‘summer drench’ in late November/December 3 weeks after feed dries off (only South-East zone and Higher Rainfall Mediterranean zones).
• Quarantine drench all introduced sheep with an effective drench that provides four actives³.
• At other times, use the Drench Decision Guide and WormTest results to make drenching decisions.

5. Manage drench resistance

• Conduct DrenchTests every 2–3 years. Use DrenchCheck-Day10s between DrenchTests.
• Avoid unnecessary drenching.
• Use effective drenches and multi-active³ combinations where possible (those shown to be highly effective on your property).
• In general, use short-acting treatments and restrict the use of long-acting products only for specific purposes or high worm-risk times.
• Rotate among all effective drench groups³ for each mob (and each paddock where possible).
• Calibrate your drench guns, dose to the heaviest sheep and follow label instructions.

¹ ASBVs=Australian Sheep Breeding Values.
² Drench refers to worm treatments regardless of route of administration.
³ Drench groups are the chemical family to which an ‘active’ belongs. An ‘active’ is the chemical in a drench responsible for killing worms. Some drenches contain more than one active and are called ‘multi-active’ or ‘combination’ drenches. See Drench groups and actives.

This is an up-to-date, integrated regional worm control program for sheep in the South Australian winter rainfall region. It builds upon earlier programs and accumulated knowledge, including from the former Department of Agriculture WormCheck program and the experience of researchers, consultants and advisers, as well as new information from the Integrated Parasite Management in Sheep project, funded by Australian Wool Innovation and ‘Parasite control in southern prime lamb production systems’, funded by Meat and Livestock Australia.

The program aims to improve the profitability and welfare of your sheep through:

• fewer deaths and illness from worms
• fewer drenches, particularly long-acting drenches
• improved productivity
• prolonged life of drenches

Acknowledgement

Authors:
Deborah Maxwell (Sheep CRC), Ian Carmichael (SARDI), Colin Trengove (University of Adelaide), Greg Johnsson (Kangaroo Island Veterinary Clinic), Simon Ellis (Ellis Farm Consultancy).

Acknowledgement:
Sheep CRC wish to acknowledge that the basis of this program is from the research performed by scientists from the former Department of Agriculture WormCheck program and the experience of researchers, consultants and advisers, as well as new information from the ‘Integrated Parasite Management in Sheep’ project, funded by Australian Wool Innovation and ‘Parasite control in southern prime lamb production systems’, funded by Meat and Livestock Australia.

Published:
June 2012

Disclaimer:
Each regional ‘WormBoss worm control program’ has been developed from local research results and experience proven to be relevant and successful for most farms in the region. Sheep CRC acknowledge that this is not the only method of worm control in the region and more refined programs can be developed in consultation with your worm management advisor/veterinarian using information and knowledge specific to your property and sheep.

Future events cannot reliably be predicted accurately. Sheep CRC makes no statement, representations or warranties about the accuracy or completeness of, and you should not rely on any information relating to the ‘WormBoss worm control program’ (‘Information’). The Sheep CRC disclaims all responsibility for the Information and all liability (including without limitation liability and negligence) for all expenses, costs, losses and damages you may incur as a result of the Information being inaccurate or incomplete in any way for any reason.

No part of this publication is to be reproduced without the permission of Sheep CRC Ltd.

© Sheep CRC Ltd 2012 (ABN: 12 125 726 847)