Back to State Outlooks

Tasmania worm update - June 2013

Paul Nilon, Nilon Farm Health, Tasmania (

You know how footy commentators work:  they espouse a theory, find a single example, and then bang on endlessly about it as if it were immutable.  Well, my new theory is that Moxidectin resistance is emerging rapidly in Tasmania.  I have had four cases in two months (which makes me an oracle).  Thus we've gone from 1/2 Mectin to Abamectin and Moxidectin in our drench tests in about two years. The interesting thing is that in all four cases Abamectin still works at close to 100%.  This is consistent with findings in other parts of the country and suggests that the resistance mechanism for mox is more complicated than for aba and ivo.  The take home message is to use Moxidectin wisely to preserve the long-acting version.

Most sheep areas have a pleasing carpet of green dust.  It has been a mild Winter but there is insufficient moisture to really get things going.  As with last month, egg counts have remained low.  Because of the good worm status some brave souls will forego the pre-lambing drench.  This should not be a universal practice.  Many producers are too distracted by cropping in the Spring to closely monitor lambing ewes for worms.  For those that omit a pre-lambing drench the fallback position is a lamb marking drench.  If all goes well they will get through to the first Summer drench at weaning.

Two good news stories:  The first is a new client who contacted me for parasite advice.  It emerged that his Merino ewe flock only gets drenched about once every three years.  After lambing they go straight to stubbles, and then to the bush.  Makes you wonder why he needed advice.

The second is NSW's monumental win in the SoO 1.  Carn' the cockroaches!!!

For June 2013 state outlooks, please follow the links below:
Back to State Outlooks