Do not assume Nematodirus is the only worm causing problems in lambs this spring, faecal egg count results on Parasite Watch Farms found other stomach worms to be challenging stock.
In North Wales, sheep farmer Owen Burns, Dan Y Deri, Corwen, who is one of 18 farmers involved in Parasite Watch, found his lambs had over 2,000 eggs per gram (epg) in samples taken in six-week-old lambs, none of which were Nematodirus.
Undoubtedly we are going to see a mass Nematodirus hatch as the weather warms up, and classically everyone talks about treating with a white wormer if Nematodirus is there. However, while a white wormer is good at treating Nematodirus, it may not reliably tackle other worms that are present.
What the results mean
When analysing results, 250 epg is a suggested limit for most worms, above this it is high enough to be causing production losses.
At Mr Burns’ farm, faecal egg counts taken on 9 April from lambs born at the beginning of March were found to have egg counts of 2,170epg
Samples were taken from lambs in a field near the farmhouse which is used every year to turn ewes and lambs out onto. The lambs would normally be treated before being turned out onto the mountain when they are a couple of months old, but they are now going to drench earlier
The warm and wet weather seen at the start of April when temperatures averaged 12-15C sparked worm activity on the land earlier than would be expected. There was not much scouring, if he wasn’t doing faecal egg counts undoubtedly he would have had some loss in live-weight gain.
The same worm pattern has been seen at the Chatsworth Estate in Bakewell, Derbyshire, where egg counts taken on 6 April in six-week-old lambs found levels at 285 epg.
Farm manager David Howlett had seen one or two lambs scouring and felt that they could be doing better. They have now been treated and he has seen an improvement in lambs. They will of course be checking on the success of the treatment with post drench tests.
Overall, the aim of Parasite Watch will be widespread evidence-based decisions to treat or indeed not treat. It will inform vets, SQPs and farmers if they are able to reduce treatments or whether the impact on production, given the parasite challenge, is likely to be too high a risk.
We have created an interactive website at www.parasitewatch.co.uk which allows you to get to know our Parasite Watch farms and the challenges they’re currently facing, check back regularly and follow us on Twitter @sheep_farmers and Facebook SheepfarmersUK for updates and commentary on the findings.
For further information, please see the product SPC, or contact your veterinary surgeon, SQP or Zoetis UK Ltd, Walton Oaks, Dorking Road, Walton on the Hill, Tadworth, Surrey, KT20 7NS. Customer Support 0845 3008034. www.zoetis.co.uk . Always seek the advice of your medicines provider. Use medicines responsibly (www.noah.co.uk/responsible). AH333/17
Dave is an RCVS advanced practitioner in Sheep Health and Production. He qualified from the Royal (Dick) Veterinary College in 2004, working mainly as a production animal veterinary surgeon, until joining Zoetis (previously known as Pfizer Animal Health) in 2010 as an Area Veterinary Manager. In 2015 Dave joined the Zoetis National Veterinary Manager team.
Dave’s areas of interest are the health and production of sheep and the sustainable control of parasites in farm animals. He is the chair of the NOAH anti-parasitics committee and sits on various national cross industry bodies including the sustainable control of parasites in sheep (SCOPS) board.
Dave is from a farming background and still manages his own flock of pedigree Texel and commercial mule sheep on the Welsh-Shropshire border.