Page 7 - Clinical Connections- Autumn 2021

Well documented causes of colitis include signs and in many cases might determine
bacterial infections such as Salmonella the clinical progression and even outcome
and clostridial species and treatment with of intestinal and non-intestinal diseases .
[7]
antimicrobials. RVC Equine is currently
evaluating a new, rapid PCR test for Future progression
Salmonella that can be performed on site The availability of next-generation
which would significantly shorten the time it sequencing technologies and
takes to make a diagnosis. bioinformatics is providing an ever-growing
More recently, equine coronavirus amount of information on factors influencing
has been identified as a cause of fever, the equine intestinal microbiota, including
anorexia, leucopaenia and colic with or nutrition, management, treatments such
without diarrhoea in adult horses in many as antimicrobials, anthelmintics and
countries including the UK. It can occur anaesthetics, animal- and stress-related
as an outbreak or only affect individual factors and pathological conditions (colitis,
horses. Treatment is supportive and diarrhoea, colic, laminitis and equine gastric
most horses recover with only few horses ulcer syndrome) .
[8]
succumbing to the disease process [3, 4] . Research into the microbiota of the
Larval cyathostominosis has long been equine intestinal tract is still in its infancy
recognised as cause of weight loss, but will undoubtedly play a large role in the
hypoalbuminaemia and diarrhoea. The future, potentially opening the way to new
availability of serological testing has now treatment and preventive strategies. Faecal
enabled veterinarians to make a tentative microbial transplantation (the administration
diagnosis of high cyathostomin burdens, of a faecal slurry from a healthy donor
including larval stages. Subjectively, by nasogastric tube), for example, is an
cases are seen more frequently which attractive concept successfully used in
could be linked to increasing resistance of human patients with Clostridioides difficile
fenbendazole and moxidectin against early infection and an ever-increasing range of
and late stage 3 and stage 4 . In addition, other conditions, including IBD. In horses, Strangulating lesion
[5]
a decrease in egg reappearance time after our own anecdotal evidence and small-
moxidectin treatment has been noted, scale studies by other investigators are References
indicating building resistance in some encouraging and further explorations of 1. 1. Durket, E., et al., Meta-analysis of the effects of
[9]
species . this treatment option are urgently required. lidocaine on postoperative reflux in the horse', Vet
[6]
Surg, 2020. 49(1): p. 44-52.
Irrespective of the underlying cause, 2. Salem, S.E., C.J. Proudman, and D.C. Archer,
intestinal dysbiosis, defined as an 'Has intravenous lidocaine improved the outcome
imbalance in microbial organism present in in horses following surgical management of small
intestinal lesions in a UK hospital population?',
the natural microflora of the intestine, often BMC Vet Res, 2016. 12(1): p. 157.
contributes to the development of clinical 3. Berryhill, E.H., et al., 'Clinical presentation,
diagnostic findings, and outcome of adult horses
with equine coronavirus infection at a veterinary
teaching hospital: 33 cases (2012-2018)', Vet J,
2019. 248: p. 95-100.
4. Mattei, D.N., J.J. Kopper, and M.G. Sanz, 'Equine
Coronavirus-Associated Colitis in Horses: A
Retrospective Study', J Equine Vet Sci, 2020. 87:
p. 102906.
5. Bellaw, J.L., et al., 'Anthelmintic therapy of equine
cyathostomin nematodes - larvicidal efficacy, egg
reappearance period, and drug resistance', Int J
Parasitol, 2018. 48(2): p. 97-105.
6. Daniels, S.P. and C.J. 'Proudman, Shortened egg
reappearance after ivermectin or moxidectin use in
horses in the UK', Vet J, 2016. 218: p. 36-39.
7. Walshe, N., et al., 'Outbreak of acute larval
cyathostominosis - A "perfect storm" of
inflammation and dysbiosis', Equine Vet J, 2021.
53(4): p. 727-739.
8. Garber, A., P. Hastie, and J.A. Murray, 'Factors
Influencing Equine Gut Microbiota: Current
Knowledge', J Equine Vet Sci, 2020. 88: p.
102943.
9. McKinney, C.A., et al., 'The fecal microbiota of
healthy donor horses and geriatric recipients
undergoing fecal microbial transplantation for the
treatment of diarrhea', PLoS One, 2020. 15(3): p.
e0230148.

For equine referrals, please call: 01707
666297
Email:
Gastric ulcer equinehospital@rvc.ac.uk

Autumn 2021 7