Victoria worms, flies and lice update - December 2017


Hamilton: Andrew Whale, Livestock Logic (a.whale@livestocklogic.com.au)
Livestock Logic Recommends frequent monitoring of stock in December and into January:

for lambs: monitor every 3 weeks, and 5–6 weeks post drench
for mature sheep: monitor every 4–6 weeks, and 8–10 weeks post drench

 This frequency of monitoring is required because:

weaner and hogget worm egg counts, in particular, are rising sharply post-weaning
this summer is high risk for causing large levels of pasture contamination

The long growing season in 2017 is starting to have its impact on intestinal parasite levels in the south west: we had a wonderful autumn break in March and conditions since then have been conducive to increasing the worm population. This means that pastures are now carrying very high levels of infective larvae that, when ingested in such large numbers can cause considerable worm damage in high risk sheep.
Consequently, we are now seeing the need for frequent monitoring (WormTest) of young sheep. Many weaners have had extreme egg counts as early as 5 weeks post weaning, with a number of post mortems showing intestinal worms as the cause of death in lambs 5–7 weeks after their first drench. It is unusual for us (Livestock Logic) to do so many post mortems of wormy sheep in December. In hoggets we are also seeing quite high egg counts that will be strongly reducing productivity. In adults we continue to see a huge variation in the need for a drench, with some ewes carrying significant burdens, while others have only received just one short acting drench in the last 12 months.
Producers, you must stay vigilant with worm egg counting over the next 4–6 weeks in particular. Conditions in January will dictate any further need for monitoring into February and March.