Welfare Implications of Racehorse Feeding Regimes
Although the racing industry is often criticised for poor welfare, an often-overlooked aspect of this is the way in which the animals are fed. The horse is by nature a trickle-feeder, with a digestive system designed to receive small quantities of forage continuously throughout the day, and would naturally graze for up to 16 hours a day (Longland & Colyer, 2002).
A prevalent health condition in racing thoroughbreds is equine gastric ulcers syndrome (EGUS), which has been found to be present in 86% of racehorses (Begg & O’Sullivan, 2003). Gastric ulcers are believed to be the result of exposure to hydrochloric acid in the stomach (Andrews et al. 2005). There can be multiple causes for this exposure:
“The gastric ulcers in horses are caused by many factors including, anatomy of the stomach, diet, restricted feed intake, exercise, stress (stall or transport), and the use of non-steroidal anti-inflammatory agents”
(Andrews et al. 2005.)
Many of these factors are present in the day-to-day management of the racehorse. Many performance horses, including racing thoroughbreds, are fed on a high energy, concentrate diet with very little forage or bulk, which can increase the likelihood of gastric ulcers (Andrews et al. 2005). This is largely because rather than eating continuously, they have large, infrequent meals. The alkaline saliva produced when grazing continuously helps neutralise the acidity of the stomach. Spending such long periods of the day without swallowing could lead to a lower stomach pH, and therefore a more acidic environment in the stomach. Intermittent feeding and feed deprivation has been shown to increase the risk of gastric ulcers, as described by Murray & Schusser (1993); Murray (1994); Feige et al. (2002), cited by Andrews et al. (2005). Racehorses are also subjected to strenuous exercise, further heightening the risk of gastric ulcers, as exercise has been shown to cause gastric compression. This in turn pushes the acidic stomach contents towards the proximal, squamous lined region of the stomach, which is the area most vulnerable to gastric ulcers (Lorenzo-Figueras & Merritt, 2002).
Although treatable, gastric ulceration remains highly common in racehorses. It has shown correlation with abdominal pain: “Gastric ulceration in mature horses has been associated with clinical evidence of abdominal discomfort (Murray et al. 1989, cited by Vatistas et al. 1999). This violates the “five freedoms” as set out by the RSPCA, notably: “Freedom from pain, injury and disease”. Although the “five freedoms” are considered aspirational, the RSPCA states that “animal keepers should always aim to provide the five freedoms to their animals as far as possible” (RSPCA, no date).
In conclusion, having examined the evidence, as there are treatments and management options available to cure and minimise ulcers, yet still such a prevalence of the condition in racehorses, it is a widespread welfare issue which needs to be addressed better than it currently is.
Reference List
Andrews, F.M., Buchanan, B.R., Elliot, S.B., Clariday, N.A. and Edwards, L.H., 2005. Gastric ulcers in horses. Journal of Animal Science,83(13_suppl), pp.E18-E21.
Begg, L.M. and O'sullivan, C.B., 2003. The prevalence and distribution of gastric ulceration in 345 racehorses. Australian veterinary journal, 81(4), pp.199-201.
Feige, K., Fürst, A. and Eser, M.W., 2002. [Effects of housing, feeding and use on equine health with emphasis on respiratory and gastrointestinal diseases]. Schweizer Archiv fur Tierheilkunde, 144(7), pp.348-355.
Longland, A.C. and Colyer, M.M., 2002. Health foods for horses. Iger Innovations, 6, pp.54-57.
Lorenzo-Figueras, M. and Merritt, A.M., 2002. Effects of exercise on gastric volume and pH in the proximal portion of the stomach of horses. American journal of veterinary research, 63(11), pp.1481-1487.
Murray, M.J., 1994. Equine model of inducing ulceration in alimentary squamous epithelial mucosa. Digestive diseases and sciences, 39(12), pp.2530-2535.
Murray, M.J., Grodinsky, C., Anderson, C.W., Radue, P.F. and Schmidt, G.R., 1989. Gastric ulcers in horses: a comparison of endoscopic findings in horses with and without clinical signs. Equine Veterinary Journal (United Kingdom).
Murray, M.J. and Schusser, G.F., 1993. Measurement of 24‐h gastric pH using an indwelling pH electrode in horses unfed, fed and treated with ranitidine. Equine veterinary journal, 25(5), pp.417-421.
Vatistas, N.J., Sifferman, R.L., Holste, J., Cox, J.L., Pinalto, G. and Schultz, K.T., 1999. Induction and maintenance of gastric ulceration in horses in simulated race training. Equine Veterinary Journal, 31(S29), pp.40-44.
RSPCA, The Five Freedoms [www document] www.rspca.org.uk/ImageLocator/LocateAsset?asset=document&assetId=1232720840053&mode=stg (Accessed 21 October 2016)
