NSW WormBoss Worm Control Programs
NSW WormBoss Drench Decision Guides
Four Worm Tests were submitted this month.
The first three test results showed low levels of scour worms in sheep that were still in good condition but without fresh paddocks for grazing. On these properties, producers were advised to monitor stock regularly, particularly in light of the current conditions that are ideal for larval development. Temperatures ranged from the mid-teens to mid-twenties. Intermittent light showers are continuing to top up the already moist soil, and surface water.
The fourth test result of 0 eggs per gram (epg) was from one mob of Dorpers from the Wanaaring district. This producer runs all his sheep in one mob within a rotational grazing system. These sheep had a moderately high worm burden when tested in January, and were subsequently drenched with a moxidectin product.
Quite a few producers are shearing at the moment. Prior to mustering for shearing is an ideal time to submit faeces for worm testing, so that if a drench is required, they can be done while still yarded.
Very few WormTests were performed in the Forbes area over the last month. The season is developing as ideal for internal parasites and will be particularly favourable when the weather warms up. Lambing ewes and weaners will be very susceptible to worms, so it is important that producers prepare 'low risk' paddocks for these mobs and continue to monitor by performing regular WormTests.
Lambs should be drenched at weaning with an effective combination drench.
Around 200mm of rain has fallen in the Nyngan and Warren area in the last month, and producers have been busy getting worm egg counts (and a few cultures) done. On the whole, although worm counts are around the 200 eggs per gram (epg) mark and seemingly not increasing (despite a couple of >1000 epg counts) we are in for a big spring worm burden if the current weather conditions continue. Most of the worms identified in the larval cultures have been barber’s pole, which seems very out of season, however, due to the warmth in the ground when the rain began, eggs have hatched and larvae have now turned into egg laying adults.
It is advised that all producers perform a worm egg count (WEC) to gauge worm burden levels in their sheep (there are many local same day turnaround options available—some at no cost). Those producers that received low worm egg count results should repeat test in 2–4 weeks, or earlier if they suspect higher burdens.
With the wetter weather we have had a few enquiries about worms.
In the western region around Deniliquin, we investigated a mob of sheep that had a distinct tail of poor doing, scouring sheep. Faecal samples were collected for worm testing, and whilst the average was only 156 eggs per gram (epg) strongyle type, an individual sheep had a count of 1040 epg. This high worm egg count indicated that worms were most likely the cause of the tail in this flock. Another WormTest result showed a count of 140 epg strongyle type eggs and 24 epg nematodirus type eggs, and a small amount of coccidia. A larval culture differentiation identified that 90% of the eggs were black scour worm type, 6% brown stomach worm and 4% barber’s pole worm.
In the eastern part of the area around Albury, two WormTests were submitted with an average WEC of 140 and 20 epg strongyle type respectively with small numbers of coccidia also identified.
Worm egg counts continue to reflect the presence of barber's pole worms. While some winter scour worms (black scour and brown stomach worms) are showing up, the highest counts still come from mobs that have significant levels of barber's pole. It is too cold for barber's pole eggs to hatch at present, but it is important to deal with these worms before spring. A worm egg count with culture to identify worm type is required. Make sure you only submit fresh dung samples, preferably collected while they're still warm.
Many graziers are talking about liver fluke, in both sheep and cattle. Recent tests on either blood or dung samples have shown increased liver fluke activity, and fluke have been found as the cause of poor sheep. Recent rainfall has recharged groundwater, providing habitat for fluke snails to breed in when the weather warms up. Left unchecked, a few fluke in stock could become a major problem next autumn. Removing fluke from stock in winter will help reduce the fluke load in paddocks with creeks and springs. At this time of year, most fluke will be adult stage, which allows a wider choice of effective drenches.
Above average rainfall since May, and with many rainy days each month, is interfering with lice control programs. Many winter-shorn sheep are close to lambing anyway, and rain is causing delays to shearing and subsequent lice treatment. Some pour-on applications will now not have sufficient time to work before lambs are born. Difficulties with muddy yards and access for heavy vehicles is hampering alternate treatments with portable dips. Monitor treated mobs for presence of lice, although they will be hard to find for several months.
Only a few worm egg count tests were conducted in the Yass region over the last month, with counts varying from 0–960 eggs per gram (epg). Barber’s pole and black scour worms were the two main players. Due to the unexpectedly wet environmental conditions over the past couple of months, producers have been advised to conduct WormTests and larval differentials (if warranted) to establish worm burden levels in sheep, especially as the odd slightly longer/warmer day is being experienced.
Enquiries about sheep lice have increased in the past few weeks, with some sheep starting to look ‘rubbed’. As producers are always quick to blame 'the neighbours' when they find lice, it is time to start a conversation with them to determine mutual shearing and treatment times, to establish cost sharing opportunities with contractors and/or to develop strategic biosecurity measures such as buffer paddocks (grazing with cattle on boundaries), while maintaining adequate fence lines etc.
It is fortunate that several very reliable lice chemicals are available for use off-shears. Treatment failures usually turn out to be inappropriate application or failure to treat, as not all sheep are shorn and treated at the one time.
Overall, few WormTests were submitted in the last month possibly because many producers routinely drench ewes before lambing without checking worm egg counts. Even so, some high worm egg counts have been seen, particularly in pregnant ewes.
It's important to remember that barber's pole can still be an issue over winter if pastures were contaminated in autumn (since hatched larvae are much more resilient than unhatched eggs). If in doubt, perform an egg count.