Results from a collaborative project between The Donkey Sanctuary and several leading research institutions offer a new way of ‘best practice’ for the control of small strongyles and other internal parasites in equids.

The collaboration between The Donkey Sanctuary, the University of Glasgow, the University of Copenhagen, and Moredun Research Institute has lead to some important breakthroughs in the trialling of a new tool designed to aid with worming.

The ultimate goal of this project was to manage the parasite population in co-grazed animals with minimal use of anthelmintics (standard de-worming drugs), in order to reduce the development rate of anthelmintic resistance and therefore preserve the use and efficacy of such drugs for animals presenting with clinical disease associated with internal parasites. 

Small strongyles are the most prevalent internal parasites amongst the UK donkey population, and their presence can cause clinical illness at high levels or even at low to moderate levels in a sick or otherwise unhealthy animal. Previously The Donkey Sanctuary relied upon routine monitoring of faecal worm egg count (FWEC) data and dosing of individual animals based on FWEC observations above a certain threshold.

This project has improved upon the existing system by using computer modelling to add additional data from a range of sources to be incorporated with observed FWEC. These include individual-animal risk factors, group management and climatological factors. The new system provides a proactive mechanism to prevent high levels of parasite transmission before they occur.

The tangible result of this project is a ‘dosing support tool’, which has been tried and tested over successive grazing seasons at The Donkey Sanctuary. It is anticipated that this system will lead to a reduction in both average FWEC and anthelmintic use across The Donkey Sanctuary. The design and introduction of this multi-faceted tool is the first of its kind for equids, and demonstrates the commitment of the animal welfare charity to safeguarding the efficacy of important anthelmintics for the benefit of donkeys and other equids globally.

Dr Faith Burden, director, research and operational support at The Donkey Sanctuary says: “The project has been a mammoth effort for all involved and the expertise provided by three of the world's most eminent equine parasitologists cannot be undervalued as they have guided us through the challenges of endoparasite control in donkeys.

“We are now able to target our anthelmintic treatment using the very best evidence available to us thus reducing our reliance on drugs. We have learnt more about the importance of land and bedding management and how to incorporate these actions in our normal husbandry practices, and have monitoring techniques in place to identify areas with significant issues with anthelmintic resistance.”

Dr Matthew Denwood BVMS PhD FHEA MRCVS from the University of Copenhagen says: “The unique size and high quality of the dataset gathered by The Donkey Sanctuary has allowed us to build a predictive model for future changes in FWEC based on a variety of risk factors at both animal and group level.” 

Dr Denwoods concludes: “Based on this model, we can improve the effectiveness of endoparasite control whilst maintaining the minimal use of anthelmintic drugs. The lessons we have learned from this project have important implications for control of endoparasites in donkeys and other grazing animals.”