25/04/2026
‼️Nematodirus Alert‼️
Timing is very important when it comes to treating Nematodirus infestation in lambs. Dosing them too early or too late can reduce how effective your treatment will be. A mass hatch of nematodirus eggs can occur rapidly and your lambs can show scour, poor growth and sometimes death. The damage is done by the worm larvae, not adult worms, so egg counts are not a reliable measure of infestation. Severe signs can occur before any eggs are passed in the dung. Due to this, you need to predict the risk of the hatch on your farm to determine the best time to dose your lambs.
This prediction is done by looking at your risk factors:
➡️Lambs eating significant amounts of grass 🌱(usually >6 weeks old but lambs from ewes with less milk will graze more from 4 weeks old).
➡️Lambs grazing pasture that was grazed by lambs last year.🐑
➡️The highest risk weather pattern is a cold spell of weather followed by a mean day/night temp of over 10 degrees.☀️
➡️South facing fields can carry greater risk of early, mass hatching as they warm up faster.🪱
➡️Lower altitudes will generally hatch earlier than higher altitudes with every 100m of elevation 🏔️ resulting in a 7-day delay to hatching.
Currently, in the Lockerbie area, hatching is generally forecast as imminent (within the next week for low altitude farms) meaning a worm dose (usually a white drench is most appropriate) should be given to your lambs in about 2-3 weeks’ time. However, some farms with warmer, heavily contaminated fields will have already hatched and should dose within the next 1-2 weeks.
Predicting your risk - The SCOPS Nematodirus Forecast is an incredible tool and should be used, but you must interpret it using your knowledge of your own specific farm conditions.
https://www.scops.org.uk/forecasts/nematodirus-forecast/
