NSW WormBoss Worm Control Programs
NSW WormBoss Drench Decision Guides
The Coonamble district has had amazing rain, which has seen abundant pasture growth after some very tough years. While I was predicting that barber’s pole worm would take advantage of the rain and flourish, all WormTests that I have seen from the Coonamble district have been very low or zero. This leads me to believe that the drought was just so long and horrible that even all the adult barber’s pole in the abomasum of sheep died before they could successfully reproduce and all larvae on the paddocks died! There are many sheep coming into the district as people restock. Producers are warned of drench resistance in other parts of the country and that sheep should be given a quarantine drench on arrival (with a combination of four unrelated drench actives; including one of the newest actives on the market, monepantel or derquantel). .
The long grass means that sheep are constantly wet and are suffering from sore feet (mainly foot abscess) and flystrike (especially the brisket) because they just cannot dry out. Producers are urged to look at the FlyBoss website or talk to their LLS Livestock Officer or District Vet and consider their options for treatment and prevention.
Cattle are suffering from insect worry, pinkeye and three-day sickness due to the large burden of mosquitoes and flies. Producers looking to control flies are advised to use a product that specifically targets these external pests, rather than use an unnecessary drench product if the cattle don't need it. Overuse of our precious drench active ingredients will speed up the development of resistance. The onset of the colder weather, which usually arrives in late April, should reduce this insect pressure, which will make life for animals and humans a lot more pleasant!
Worm egg count (WEC) results have been mixed throughout the Young area; ranging from 0 epg to > 500 epg. Now is the perfect time to be carrying out WECs with the recent rainfall, pasture growth and mild weather. The fact that many flocks in the region are leading up to lambing makes it even more timely. Extra care and attention should be paid to pregnant ewes’ worm burdens as their immunity temporarily declines at lambing and during lactation. Pregnant ewes should have a WEC carried out (and be drenched if indicated) prior to being moved onto their lambing paddock so that the build-up of a worm population in that paddock is delayed. With some pregnant ewe mobs returning counts of 0 epg, it is a reminder that carrying out WECs can be a money saving tool that prevents unnecessary drenching and allows informed decisions to be made. The range in results this month should encourage producers to carry out their own WECs rather than rely on general trends in the area.
The fly population is also enjoying our recent change in weather, leading to an increase in flystrike. Producers are encouraged to check sheep regularly.
Barber’s pole worms have not shut down despite the current COVID-19 pandemic!
Thankfully, rain events and mild weather are continuing around the region; however, this means we are consistently seeing the impacts of barber’s pole worm. Some producers have been caught a little by surprise with rapid increases in these worms causing clinical disease. Just another reminder to continue with regular WormTests!
By now the preparation of low worm-risk lambing paddocks is well underway for many producers. This aims to provide paddocks with minimal worm contamination at the time of lambing, when animals are particularly susceptible. This strategy is very effective on the tablelands and is ideally followed up with the preparation of low worm-risk weaning paddocks.
Worms are often blamed for all of the sheep deaths that occur on-farm, however, it is important to also consider other diseases that might also be playing a part. Northern Tablelands LLS can assist with disease investigations and are still operating and able to conduct property visits as required. So please get in touch if you need advice or assistance with animal health issues.
Around Narrabri we have had very low worm numbers for several years. With recent rainfall and the subsequent introduction of sheep from all around the country, producers are advised to be aware that worms may become a problem again in the near future. We recommend conducting a WormTest on your weaners every 6–8 weeks through the cooler months to keep an eye on worm levels, but if there is or has been some significant rain (enough to grow some green grass), WormTest mobs, including adults, 4–6 weeks afterwards. Also, ensure that all new arrivals receive a quarantine drench on arrival—we don't want to be introducing drench-resistant worms.
Introduced worms that survive an inadequate quarantine drench, and those already in your flocks, will gradually increase in number within your sheep and their eggs will contaminate your newly growing pasture. Unlike previous years, where there has been no feed on the ground to protect the eggs, this year, there is plenty of dry matter on the ground meaning that eggs are protected and will survive longer in the environment than they did during the drought. Over the coming months it will be important to manage these worm burdens in pastures, particularly when selecting paddocks for lambing and weaning. So, be alert, but not alarmed, at this stage, and conduct regular WormTests.
April is a great month for monitoring for worms and fluke. It gives us a huge amount of information for current drenching needs as well as assisting us to prepare low worm burden pastures for spring and maintain control over barber’s pole worm.
WormTests are worth doing at this time of the year as worm problems can rapidly accelerate due to ideal moisture levels and warmer day time temperatures. Where sheep have been in feedlots, and pastures underwent a hot, dry summer spelling, worm counts might be very low, especially if they are now grazing highly nutritious clover and on an increasing nutritional plane. In this case, drenching may not be required. However, if sheep have been in the paddocks, eating close to the ground and are nutritionally pushed, there may be base numbers of worms that are now rapidly multiplying. This particularly applies to barber’s pole worm, but scour worms may also be on the increase. A WEC test is the best way to monitor the worm levels in the sheep for their requirement for drenching, but you should also watch for signs of scouring, anaemia or a tucked up appearance.
Worm counts have been showing higher, relative Nematodirus counts. This is because these worms have a tough eggshell that can resist desiccation and survive long periods of time waiting for the drought-breaking rains to hatch. This worm type can particularly cause scouring in younger weaners and this can occur even before these newly ingested worms have started to lay eggs. This is a disease to watch for, particularly in your young sheep.
Autumn is a beneficial time to monitor for fluke and control if required. Many private veterinary practitioners are taking the little extra time to value add to their visit by collecting some blood samples for the fluke ELISA from cattle while doing the pregnancy testing.
By doing a pooled fluke ELISA blood sample (of 5 samples) from each mob you can do some very effective surveillance to assess your requirement for an expensive fluke drench.
Monitoring for fluke in sheep is still best done by requesting the extra fluke test on top of your regular WEC test.