Horse owners in North Wales have been advised to be on alert for small redworm after several cases of high small redworm burden were reported in the area.
Small redworms, or cyathostomins, are the most common worms found in horses and ponies in Wales. If left untreated, they can cause severe illness and even death.
Vet Patrick Scott of Milfeddygon Dolgellau Cyf is urging owners to get their horses tested for small redworm. If treated early, the animal is less likely to require hospitalisation and antimicrobial treatment.
Reducing the need for such treatment is also an important part of the fight against antimicrobial resistance (AMR), an issue that is vital for animal and human health.
Patrick said:
“Small redworms reside in the horse or pony’s large intestine. Adult worms lay eggs, which are passed on to the faeces. The eggs hatch on the pasture and develop into larval stages, which pass back into the horse or pony as they graze. During the life cycle, the small redworm larva burrows into the gut lining, where they re-emerge as adults, and the life cycle starts again.
“However, during autumn and winter months, these larvae will hibernate in the gut instead of developing into adults – a process known as encysted red worms/encysted cyathostomins.”
A horse with a high adult worm count may present clinical signs such as weight loss, dull coat, and soft faeces. While a high adult worm count can be confirmed through faecal egg counting (FEC), at this stage of the life cycle, small redworms can only be detected by taking a blood sample.
This allows target worming using the correct product, at the right time of year to the horse that requires it. It is no longer acceptable to randomly blanket treat horses/ponies for worms. A more thorough and accurate approach improves health and welfare and helps to reduce the occurrence of anthelmintic resistance which is a growing problem
Patrick said:
“The encysted stages of redworms are much more dangerous when in higher numbers when compared to a high adult worm count. An ‘en-masse’ emergence of larvae can lead to severe watery diarrhoea, weight loss, colic, and colitis/ endotoxaemia, with up to 50 % mortality.
“Therefore, a routine blood sample at this time of year is vital to establish a worm burden level and ensure good health.”
Patrick has undertaken equine health clinics for Milfeddygon Dolgellau Cyf clients as part of the Arwain DGC (Defnydd Gwrthficrobaidd Cyfrifol / Responsible Antimicrobial Use) programme.
Funded by the Welsh Government, the award-winning Arwain DGC programme helps vets, farmers, and horse owners in Wales to reduce the risk of AMR by promoting animal health and productivity, training, the application of new technology, data gathering, and research.
AMR is classed as a ‘One Health’ challenge – as antibiotic resistance threatens the health of humans and animals. The World Health Organisation has warned that AMR is an issue where “without urgent action, we are heading for a post-antibiotic era, in which common infections and minor injuries can once again kill.”
Patrick said:
“Horses with high burden of small redworm often require hospitalisation, thus requiring anti-microbial treatment. It is paramount that if we are to reduce this anti-microbial usage, especially the use of critically important antibiotics that often have to be used due to the increased presence of resistant antibiotics, there is a combination of good husbandry and monitoring.
For example, low stocking density and faecal removal from pasture, FECs throughout summer months, and annual blood testing at critical points in the year to reduce the morbidity of this disease.”
Katy Hurley, Arwain DGC marketing and equine events officer, said:
“We would like to echo Patrick’s message and encourage horse owners to be pro-active in all aspects of their horse’s health.
“Prevention is always better than cure so make sure you speak to your vet to discuss the right testing for your animals and how to keep them in top condition. Arwain DGC recently held a webinar for horse owners which gave some great advice on keeping horses healthy, and a recording of the webinar is available to view on our website.”
https://rhaglenni.mentera.cymru/arwaindgc/en/arwain-dgc-videos/
