The purpose of this study was to gain evidence on the prevalence of dental abnormalities in stable-kept horses in comparison
with free-living horses. It is expected that free-living horses that graze for as much as 16 h/day will have fewer dental
abnormalities than stable-kept horses. In this study, the latter group was fed a diet that was based on a relatively high-energy,
cereal-based feed. This was thought to be a representative of common practice in domesticated, stable-kept horses. Compound
diets such as this have previously been shown to increase the frequency of chewing cycles and decrease mediolateral excursion.
The occurrence of 10 named dental abnormalities present in the dentition of 60 Thoroughbred-type horses was recorded.
Half of the population was at grass all year round in New South Wales, Australia. The remainder were stabled for 24 h/day in
Gloucestershire, UK. All horses were between 5 and 15 years of age. The same, experienced, equine dental technician examined
all horses using a full-mouth speculum and produced a routine dental chart.Stable-kept horses had a significantly higher total
occurrence of abnormalities (P,0.001) than free-living horses. The stable-kept group had a significantly higher prevalence of
exaggerated transverse ridging across the occlusal surface of the cheek teeth, focal or ramped overgrowths of the cheek teeth
and periodontal disease (P,0.01 in all cases). All horses in both groups had some occurrence of sharp edges of the buccal
and lingual edges of the cheek teeth. The results are in agreement with anecdotal evidence that a fibre-based, grazed diet
results in fewer dental abnormalities. However, sharp edges may occur even with what is perceived as a ‘natural’ diet.