A team of researchers led by Tim Mair, CVS equine veterinary director and specialist in both equine internal medicine and equine soft tissue surgery at Bell Equine Veterinary Clinic, aims to investigate and document the clinical and clinicopathological features, treatments and outcomes of colitis in UK adult horses.
There is very little published data on the underlying causes and outcomes of colitis in adult horses in the UK. Most published studies originate from North America. It is recognised that the causes of colitis vary in different geographical locations, and some of the diseases causing colitis in North America are not present in the UK.
Colitis is a serious and life-threatening disease in horses. Affected animals present with diarrhoea and can rapidly become dehydrated and toxic, resulting in severe shock, multi-organ failure and death. Reports from North America suggest that about 50 percent of affected horses will die of the disease, despite attempted treatments.
There are many potential causes, including a variety of different bacterial and viral infections, parasites and toxicities. Unfortunately, the clinical signs of colitis (diarrhoea and signs of hypovolaemia/endotoxaemia) are often similar regardless of the cause.
Diagnosis of the underlying cause depends on laboratory testing, but in many cases (around 50 percent), no precise cause will be established. This limits the ability to provide specific treatment. In addition, the cost of laboratory testing prevents many owners from undertaking the full range of diagnostic tests.
The new study will review 100 cases of colitis in adult horses and 100 controls referred to seven equine veterinary hospitals in the UK: five CVS equine veterinary hospitals as well as Rossdales Equine Hospital and the University of Liverpool’s equine hospital.
A set of diagnostic tests on blood and faeces will be performed in these horses. The laboratory tests will include small redworm serology, culture and PCR of faeces for Salmonella spp, PCR of faeces for Clostridioides difficile and Clostridium perfringens, ELISA of faeces for toxins of C.difficile and C.perfringens and PCR of faeces for coronavirus. The clinical features, laboratory results, treatments and outcomes will also be recorded.
Tim Mair said: “Acute colitis accounts for around 5 percent of admissions to referral hospitals. Of those who are referred to it, half will not survive, but there is very limited evidence available. So it’s vital that we build our evidence base of this life-threatening condition. We hope that the outcomes of our new study will lead to a greater understanding of the causes and better inform veterinary treatment of colitis in UK adult horses.”
The Colitis in Adult Horses study is supported by a research grant from CVS, and funding for the small redworm ELISA will be given from Austin Davis Biologics. The study started at the beginning of 2024 and the first horses have been recruited. The results of the study are expected to be published in 2025.
CVS Equine provides a complete range of industry-leading veterinary services to patients and clients in over 22 sites across the UK. Its ambulatory veterinary surgeons are supported by a team of over 20 recognised veterinary specialists in fields including medicine, surgery, dentistry and diagnostic imaging. Based within a network of referral centres, the specialist team provides a first class service to referring vets and a multi-disciplined approach to the treatment of all equines, from donkeys and pleasure horses to elite athletes. Through an unrivalled commitment to investment in equipment, facilities and research, all of its practices are able to offer the latest veterinary treatments, diagnostic services, advice, standards and support. For more information about CVS Equine visit the website.