NSW WormBoss Worm Control Programs
NSW WormBoss Drench Decision Guides
In the Young area and its surrounds worm egg counts have been on the lower side, with a spectrum of 0–280 epg reported from mid-late April till mid-May. Incidental findings of barber’s pole worm on property visits have also occurred, but nothing to cause production issues. Recent rain events, including this week’s predicted rain of 1 inch in the Young area, have re-iterated the need for producers to stay on top of any worm burdens that may be in their respective paddocks. Temperature fluctuations have been from -1ºC at night time to 22 or 23ºC during the day, allowing larval activity to continue during the days when temperatures hover towards the 20s. WormTests for young mobs of sheep and pregnant ewes due to lamb have been advocated with checks or re-checks conducted 4–6 weeks later.
There has been some reduction in the number of worm egg counts seen in the Wagga Wagga area over the past few months. Results we have seen indicate barber’s pole worm still accounts for high percentages of worms when a burden is seen. While we have seen one individual burden of fluke in weaner calves, there is not enough data to indicate a significant area issue.
Ewes have started lambing; however those farms lambing later in the season should be considering their pre-lambing drench. Worm Test results with egg counts greater than 100–200 epg should consider drenching 2–3 weeks prior to lambing, in conjunction with pre-lambing vaccination.
Consideration of weaning pastures and preparation should be well under way. Ewes and weaner lambs should be drenched at 12–14 weeks post-lambing and moved onto low risk pasture. Early weaning at 12–14 weeks of age is important to ensure early separation of two age classes reducing risk of egg exposure as well as nutritional competition; this has concurrent trade offs for return to joining weights in ewes.
Management of this year’s weaner pastures is particularly important with the residual high levels of barber’s pole across the area. Barber’s pole larvae survive well in cold and dry conditions. Ensure low risk grazing pastures such as stubble or forage paddocks, paddock grazed by cattle for 2–3 months of summer or 6 months for cooler months, or pasture not grazed by sheep younger than 18 months of age.
About half the worm tests done lately show a significant proportion of barber's pole worms, and the timing of the recent autumn break will ensure there are larvae on the ground through winter. Frosts do not kill barber's pole worm larvae already on pasture. This will influence your choice of pre-lambing drench. Avoid using single-active drenches, especially abamectin on its own, if barber's pole worms are present in your sheep. A worm egg count and culture is recommended if you are unsure.
If no barber's pole worms are present, many mobs of adults still have very low worm egg counts. It is a good year to give long-acting pre-lamb treatments a rest in these flocks, providing you have made some attempt to minimise worm contamination of lambing paddocks. At the same time, ‘scour worm’ burdens in young sheep are on the rise, with brown stomach worm in particular starting to reach drenching thresholds. These young sheep still look OK, but worm levels will be affecting production. They will also be contaminating pastures, so paddocks where lambs and hoggets have grazed since Christmas would not be ideal for lambing.
Liver fluke are making a come-back after several years of minimal activity in this district. Sheep and cattle tests are increasingly positive for liver fluke in stock which have grazed creeks and low-lying swampy areas over summer and early autumn. A fluke drench in late autumn is part of a routine fluke control program. Select a drench with high efficacy against immature liver fluke at this time of year.
Only a few worm tests were done in the Monaro region this month with counts ranging from around 100 eggs per gram to 900 eggs per gram. Many farmers have reported having great difficulty with barber’s pole worms, especially in their weaners, over the last month. Many of these infestations have been detected based on symptoms such as a tail in the mob, weak lambs that go down and are reluctant to move and pale to white gums, or at post mortem where large numbers of the adult worms are seen in the abomasum.
Fortunately, the colder temperatures have arrived which will slow down worm activity especially of the barber’s pole, although scour worms can still be causing problems. A worm egg count should be done now if your sheep are showing signs of worms, such as scouring or ill thrift, or one month prior to lambing.
This month has seen a decrease in the amount of worm activity reported. There have not been any reports of barber’s pole in the district this month; the last reported cases were in the east in April.
Good rain throughout March and April has lead to ideal conditions for barber's pole worm survival. Temperatures in May have been quite variable but mostly mild with warm days and cool nights. Only a couple of mild frosts so far. Worm egg counts have backed this up with many reports showing counts in the thousands. However, reports of deaths and productivity issues related to worms have been non-existent. Many a drier autumn has seen a lot more barber's pole issues arise, so producers must be doing something right or possibly just got out of sheep.
No worm tests submitted this month—very dry and people are offloading stock or feeding and/or pushing scrub.