Queensland worms, flies and lice update - March 2017

Brisbane: Maxine Murphy, Veterinary Parasitologist (maxine@paraboss.com.au)

Barber’s pole worms, especially those in undrenched sheep, usually peak in March although the peak this year is likely to be somewhat reduced due to the earlier searing temperatures (above 35°C) and dry conditions that would have decimated the number of worm eggs and larvae on pastures. The current return to conditions ideal for barber’s pole means that eggs excreted by any adult worms still alive in sheep, will now cycle into infective larvae.

Monitoring the situation with worm egg counts will track the build-up, as in many areas the grass is/soon will be green and actively growing; visual indicators for larval survival on pasture. While good feed may mitigate the effects of a worm burden in older stock, it doesn’t always in younger stock. If egg counts in drenched mobs are elevated 14 days after drenching, then it’s time to ask, ‘why’. Was it due to drench resistance or poor drenching technique?

The current availability of premixed, short-acting, multi-active combination drenches on the market makes managing drench resistance easier. One such drench back on the market and now in combination form is NAPfix®. It is a ready-to-use triple combination drench that contains naphthalophos (OP), abamectin (ML) and albendazole (BZ). Many producers are wary of the OP drenches, but this ready-to-use product should remove the earlier concerns about determining correct dose rates, and as there is no mixing required and no dust, the risk of OP exposure to farmers is reduced. Nevertheless, it is important to read the label very carefully and follow the manufacturer’s recommendations. 

Texas: Noel O’Dempsey, Sheep Veterinary Consultant (odempseyn@gmail.com)

We have had good rain over the last few days. It is easy to imagine that everyone has been as fortunate when you can hear rain on your roof. We will face increased barber’s pole activity in our sheep. Worm Egg Counting (WEC) will keep us ahead of the game and ensure that the problem does not get out of hand. For people relying on ‘keeping a close eye on the sheep’ often production losses can be significant before signs are noticed. WormBoss has a list of laboratories  providing WEC and culture facilities.