Paul Nilon, Nilon Farm Health, Tasmania (firstname.lastname@example.org):
Most of Tasmania received a good rain in mid March. While it was insufficient to guarantee an autumn, it was enough to kick-start the worms. WECs have risen dramatically in the last two weeks after a long and welcome hiatus. This correspondent has fielded questions from several clients about the wisdom of an autumn drench as an alternative to a second summer. The answer has been yes: it just shows that with global warming Tas is rapidly emulating WA.
Many dry sheep are still on permanent pastures, doing crop clean-up duty, or having a holiday in Siberia (the bush). These animals should not need an autumn drench unless returning to permanent pastures with a decent egg output (say, greater than 300 epg). Weaners on permanent pastures are most at risk from emerging worm challenges and have great potential to contaminate pastures.
Finishing lambs on irrigated pastures may now be facing considerable challenge. Suggest they be monitored every 3 weeks with a trigger of around 200 epg, being mindful withholding periods and ESIs for any drenches.