Parasite control & grazing systems for horses: The North-Western European perspective

Take home message

In temperate climates monitoring of worms through egg counts in order to keep pastures safe is a relatively new recommendation. The aim of such a Selective Anthelmintic treatment System (SAT), aimed mainly at strongyle worms, in horses:

• Is slowing down resistance development against anthelmintics (and check efficacy);
• through treatment of horses that are “high” strongyle egg shedders (not treat the others);
• targeted treatments also against specific other parasites, for example against Parascaris spp
• Anthelmintics may also burden the environment through residues, therefore treat animals only when warranted

In the Netherlands a parasite compendium was developed that integrates grazing management for several animal species. These tools we especially use for teaching veterinary students about helminth control strategies. For more information please visit: https://www.parasietenwijzer.nl/e/

[...]

References

• Becher, A. M., van Doorn, D. C. K., Pfister, K., Kaplan, R. M., Reist, M., and Nielsen, M. K., 2018. Equine parasite control and the role of national legislation - A multinational questionnaire survey. Veterinary Parasitology, 259, 6-12. https://doi.org/10.1016/j.vetpar.2018.07.001
• Boersema , J. H., Eysker, M., and Nas, J. W. M., 2002. Apparent resistance of Parascaris equorum to macrocylic lactones. Vet Record, 150 (9), 279-81. https://doi.org/10.1136/vr.150.9.279
• Döpfer , D., Kerssens, C. M., Meijer, Y. G. M., Boersema, J. H., and Eysker, M., 2004. Shedding consistency of strongyle-type eggs in Dutch boarding horses. Veterinary Parasitology, 124 (3-4), 249- 258. https://doi.org/10.1016/j.vetpar.2004.06.028
• Eysker, M., Bakker, M. J., van den Berg, M., van Doorn, D. C. K., and Ploeger, H. W., 2008. The use of age-clustered pooled faecal samples for monitoring worm control in horses. Veterinary Parasitology, 151 (2-4), 249-255. https://doi.org/10.1016/j.vetpar.2007.10.008
• Geurden, T., van Doorn, D., Claerebout, E., Kooyman, F., De Keersmaecker, S., Vercruysse, J., Besognet, B., Vanimisetti, B., Frangipanedi Regalbono, A., Beraldo, P., Di Cesare, A., and Traversa, D., 2014. Decreased strongyle egg re-appearance period after treatment with ivermectin and moxidectin in horses in Belgium, Italy and The Netherlands. Veterinary Parasitology, 204(3-4), 291- 296. https://doi.org/10.1016/j.vetpar.2014.04.013
• Lendal, S., Larsen, M. M., Bjørn, H., Craven, J., Chriél, M., and Olsen, S. N., 1998. A questionnaire survey on nematode control practices on horse farms in Denmark and the existence of risk factors for the development of anthelmintic resistance. Veterinary Parasitology, 78 (1), 49-63. https://doi.org/10.1016/S0304-4017(98)00117-4
• Pfister, K., and van Doorn, D. 2018. New Perspectives in Equine Intestinal Parasitic Disease Insights in Monitoring Helminth Infections. Veterinary Clinics of North America: Equine Practice, 34 (1), 141- 153. https://doi.org/10.1016/j.cveq.2017.11.009
• Ploeger, H. W., van Doorn, D. C. K., Nijsse, E. R., and Eysker, M., 2008. Decision trees on the web - a parasite compendium. Trends in Parasitology, 24 (5), 203- 204. https://doi.org/10.1016/j.pt.2008.02.001
• Römbke, J., Duis, K., Egeler, P., Gilberg, D., Schuh, C., Herrchen, M., Hennecke, D., Hölzle, L. E., Heilmann-Thudium, B., Wohde, M., Wagner, J., and Düring, R.A., 2019. Comparison of the environmental properties of parasiticides and harmonisation of the basis for environmental assessment at the EU level. UBA-Texte 44/2019. ISSN 1862-4804.