New arrivals should be given a “quarantine drench” and kept from pasture for 6 to 8 hours until it has had a chance to act. This reduces the possibility of them contaminating your pasture (see below) and other sheep.
Overdosing sheep or lambs with drench or incorrect pre or post drenching management can be fatal so it is important to consider how you drench as well as 'when' and 'what with'. Key drenching principles include: Always read the product label for both dosage and safety information.
Before dosing sheep with an oral white or clear wormer, best practice is to have a 24-hour fasting period. This optimises absorption in the stomach.
Using a drench gun, they are applying an anthelmintic dose into the throat of each sheep to kill internal parasites. People sometimes confuse drenching with dipping, which involves applying a chemical solution to kill external parasites, often by getting the sheep saturated.
If the WEC is high, you should promptly drench every sheep in the mob. If the mob will not be moved to a low-worm-risk paddock after drenching, consider scheduling a second drench in six weeks.
A typical sign of a worm problem is unthrifty sheep. An unthrifty sheep is one that is not eating properly, is losing condition, tends to lag behind the mob when moved and, in severe cases, is clearly weak. A worm problem often (but not always) results in sheep scouring and becoming daggy.
Secondly, worming every three weeks may work in the short term, but it will increase the risk of resistance in the mid/long term (plus you may be doing it more often than you need, hence wasting your money and time).
Your sheep may already have a case of drench resistance and you will need to consult your vet for advice. You should conduct a follow up worm egg count between 10 and 14 days after your sheep are drenched to see if the treatment has been effective.
Goats and Sheep: 1 fl oz = 30mL (cc) per 100 lbs. body weight. Maximum of once every 8 hours, as needed. Medication: Administer Nutri-Drench 15 minutes prior to giving any medications.
Most adult sheep have low worm egg counts in early summer and a drench at that time is not warranted; delaying a drench until late March or April allows some less-resistant worms to survive.
As sheep are somewhat crepuscular, in my observation, they tend to eat in the morning, chew cud in the afternoon, and then eat again as evening falls. Unlike humans, sheep doze in small amounts throughout the day and night but don't engage in a lot of deep, long sleep.
However, evidence with sheep is less clear; one study demonstrated feeding did have an effect (1): 65% of lambings occurring within 4 h before, and 8 h after feeding – therefore feeding in the morning was recommended.
B - Keep them off pasture for 24-48 hours so that all the worm eggs have been passed.
Sheep weather alerts
High rainfall and high winds combined with temperatures below normal will cause mortalities in young animals, especially newly shorn sheep without shelter. The impact of the cold weather will depend on its duration, rainfall, wind speed and temperature—the 'wind chill' factor can double heat loss.
Symptoms of sudden collapse, convulsions, and rapid death were described when carbon tetrachloride and paraffin drenches are deliberately administered into the trachea or mouth rather than by the correct route in an attempt to provoke aspiration of some of the compound.
Dry conditions force parasites to stay at the base of the plants where they are less likely to be consumed by the livestock. Sheep (and goats) are generally not affected by the same internal parasites as cattle and horses.
Adult sheep should be wormed 2-4 times a year, more frequently if you notice your flock is thin or if you are not using an effective rotational grazing plan. What is this? I recommend rotating Ivomec with Safeguard or Cydectin. A once-annual treatment with Valbazen for tapeworms is also a good idea.
Traditionally, most flocks have wormed ewes at lambing. This practice is designed to combat the drop in immunity to worms that ewes experience from around 2 weeks before lambing to 6 weeks afterwards.
Additionally, sheep this time of year tend to have a thicker fleece and, as a result of rain and wet weather, this can become very heavy. The weight of their fleece can cause them to tip over on to their backs and makes it exceptionally difficult to get back up.
Most pour-on and injectable drenches only last 14-42 days.
A sign sometimes seen with barber's pole worm infection is the so-called 'bottle-jaw', a fluid swelling beneath the jaw. This is caused by a chronic shortage of protein in the animal's bloodstream and is associated with a number of diseases, not only haemonchosis.
SCOPS - Sustainable Control of Parasites in Sheep
- When worming sheep/lambs do not dose and move onto clean pasture: This will increase the proportion of resistant worm eggs on the pasture and therefore encourage resistance.
Worms can live in the sheep's gut for many months. Some species can live exposed on the ground for six months or longer in favourable conditions. Black scour worm is the most common type of internal parasite causing infection in Australian sheep flocks.
One of the most important times to deworm is just after lambing, when there is a sudden release of infective eggs within the ewe's intestinal tract. Treating animals at this time minimizes the exposure of larva to newborn and young lambs.