Maxine Lyndall-Murphy, WormBuster Lab, Brisbane (Maxine.Lyndal-Murphy@deedi.qld.gov.au):
It's lambing time and for most producers the decision to drench or not was fairly clear: most opted for a long-acting product as worm egg counts were above 300epg, with many above 2000epg.
On those properties that experienced heavy Haemonchus (Barber’s Pole) activity last summer, monitoring with worm tests must become a priority as the weather warms. Overwintered pasture larvae and larval progenyfrom high burdens carried by lambing/lactating ewes will increase their activity as the weather warms, with a resultant increase in numbers on pastures - keep a close watch on lambs.
The main point is that you should be aware that worm activity did not stop over the cooler months, it just slowed. In most areas during winter, day temperatures were consistently above 20C.
We are currently seeing many mobs in need of drenching even though lambing has started. Wormy pastures leading into summer will be a disaster for weaners over the summer months if rainfall is above average.
First step: the drenches you use must be very effective. Testing is the only way to be sure.
Some pastoral regions are reporting a bit of fly around.