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Western Australia worms, flies and lice update - August 2015

WA WormBoss Worm Control Programs

WA WormBoss Drench Decision Guides


Esperance: Nicole Swan, Swan’s Veterinary Services (nicole@swansvet.com)

The majority of faecal worm egg counts have been low, with only a couple of mobs requiring drenching. Some mobs that are scouring are otherwise well and this is most likely a nutritional scours due to the lush feed.

We are now getting close to weaning. Weaning is an ideal time to conduct a Drench Resistance Test (DRT) to determine the resistance status of drenches on the farm. This test requires using undrenched weaners. If you feel that conducting a DRT is appropriate on your property then contact your veterinarian. The DRT can be tailored to best suit the history of your farm. Previous test results will influence which groups are tested. If you have not conducted a DRT then the drenches you have been using will be considered when organising the test groups.

Remember it is important that the test sheep do not have any Barbers Pole as this will affect the test results. 

Editor’s notes:
The issue of using previously undrenched lambs at weaning for a Drench Resistance Test is currently being discussed in the ParaBoss Technical Forum, as there is some concern that maternal (ewe) effects on the lambs may affect the results. Watch for an update in a coming edition of ParaBoss News.

Drench Resistance Tests can be carried out when both barber’s pole and scour worms are present, by also conducting a larval culture on each test group. The benefit is that the drench efficacies can be calculated for each worm for each drench. It is quite common that one worm species on a farm has quite a different level of drench resistance to a particular drench active than another worm species on that same farm.