Worm Heat Map – October Edition

September has seen a rise in worm egg counts. This spring rise in worm egg counts coincides with the start of lambing and warmer weather conditions. Monitoring WECs during spring is essential to stop worm numbers getting out of control during the summer and autumn months. Lambing onto low worm risk pastures, prepared in the autumn, is a critical management strategy to keep worm burdens under control at this time. Worm risk is greatest on the eastern side of the tablelands, with an average WEC of 649 epg. This has increased since July but remains below last year's level. 

Monitoring at this time of year should be a routine management strategy. In more pastoral regions, monitoring should be performed a few weeks after any rainfall activity.

In the east, worm egg counts have increased this month but the region remains in the same risk category, shown as yellow on the map. In the west, worm egg counts have jumped and the region joins the same risk category as the east. Both regions have seen several WEC samples return results above 750 epg, with more than 10% of results in the eastern zone greater than 1000 epg. 

With lambing well under way, monitoring ewe WECs at lamb marking and pre-weaning provides information about the effectiveness of worm control management. Weaning lambs onto lower risk pastures will assist with worm management during spring and summer. 

In the south, worm burdens remain at similar levels to August. Compared to last month, worm challenge is a marginally lower in the west, with an average WEC of 347 epg. However, this count is higher than in the eastern zone where the average WEC is 194 epg. 

While the majority of results from both these regions are below 250 epg, multiple samples have returned counts above 500 epg, which is very high for this region. This variation in results is a good reminder to test your own flocks rather than rely on regional averages.

The increase in WECs seen in eastern Victoria last month has not persisted, and the current low WECs have resulted in this area being classified as green and considered low risk. Rainfall seen in some parts during September may see a late spring rise in WECs, so monitoring of young sheep will remain important.

Western Victoria has experienced a rise in WECs, with the Gippsland region appearing orange on the map and reporting an average WEC of 416 epg. Surprisingly for this region and time of year, 30% of samples had very high WECs above 1000 epg. Similar trends are visible in the north-east region, but of a lower magnitude.

Worm activity remains very low in the south-east of the state, which remains categorised as green. Although worm numbers are currently low, the high sample submissions indicate farmers are staying alert in tough conditions. Despite the low worm challenge, the large number of samples submitted shows that farmers remain vigilant against rising worm numbers in challenging conditions.

In Western Australia, the southern region is experiencing a sustained  moderate worm challenge (shown as yellow, with average WEC 344 epg). In the south-west and central regions, worm challenge remains low. Some good rainfall in the south-west may see worm numbers increase in October.