Published online by Cambridge University Press: 23 November 2017
Laminitis is often recognised as one of the most common causes of lameness in horses. This painful condition has obvious far-reaching implications for the welfare of affected animals, yet, despite the prevalence and seriousness of laminitis, the exact aetiology of the disease has still to be unanimously identified. It is generally accepted that acidosis within the hind gut of the horse is a predisposing factor to the onset of laminitis (Bailey et al., 2003). Fast digestive transit times and low production rates of α-amylase, result in the horse being relatively inefficient at the breakdown of starch within the small intestine. Rapid fermentation of cereal starch in the caecum and dorsal colon will ultimately yield lactic acid and can culminate in changes to the caecal bacterial populations (Bailey et al, 2003). Rising lactic acid levels, coupled with a drop in pH will result in the development of acidosis. It is believed that a window of opportunity exists between the occurrence of acidosis and the development of the symptoms associated with laminitis (Al Jassim, 2005) in which changes to diet could be made, thus preventing the eventual onset of the disease. It has been established that faecal pH is intrinsically linked to caecal pH, and studies reporting diet-induced pH changes in both horses (McLean et al., 2000) and pigs (Cahn et al., 1998), have shown close correlation between faecal and caecal pH. It is therefore postulated that faecal pH may be an indication of acidotic conditions within the hindgut of the horse and a faecal test to indicate acidotic status would obviously be of benefit. The aim of this study was to investigate optimal collection times of faecal samples destined for pH analysis, and to establish whether time of feeding significantly altered faecal pH, thus enabling further work to be carried out on the development of a faecal test for acidosis.