Nutrition: From Racehorse to Ancient Shetland

The impact of diet upon physiological systems such as the digestive tract, respiratory system and skeletal system has commonality between breeds as diverse as Thoroughbreds and Shetland ponies and also has no ageist barriers. Whilst there may be some differences in the subtle functioning of the gastrointestinal tract between ponies and Thoroughbreds, for example in terms of voluntary dry matter intake and diet digestibility (Cuddeford et al. 1995), the nutritional pitfalls remain remarkably similar.

One of the greatest limitations of the equine digestive system is the seeming ease with which the hindgut ecosystem can become disrupted by an increased influx of rapidly fermentable carbohydrate, either in the form of undigested starch (Medina et al. 2002) or grass fructan (Milinovich et al. 2008), with often severe health consequences in the form of colic, colitis or laminitis. Despite the evidence that large high starch meals, uncooked cereals and inadequate levels of forage can significantly contribute to hindgut acidosis (Medina et al. 2002; Julliand et al.2006) tradition amongst the racing and performance horse communities remains firm, adding to a heightened risk of digestive disorders. Equally, many pony owners battle against a pony’s ingrained over consumption of grass and recent evidence suggests that this ‘will to feed’ is high in these animals which can consume up to 40% of their daily dry matter intake in 4 h or less (Harris and Geor 2007). Whilst adjustments in feeding management are to be applauded in both these scenarios, other additions to the diet such as live yeast probiotics and hindgut buffers may offer some benefit. Live yeast probiotics (saccharomyces cerevisae), which should be distinguished from bacterial probiotics for which in contrast there is little supporting evidence, have been shown consistently to ameliorate the impact of a high starch diet on the hindgut environment and ecosystem (Julliand and Zehner 2008). Equally, preliminary data on encapsulated bicarbonate is interesting regarding its potential in buffering hindgut acidity (Pagan et al. 2007). [...]