Effect of dental correction on feed digestibility in horses

To test the hypothesis that routine dental correction (removal only of shar p hooks and points from molars and premolars) would improve digestion of a hay/grain ration whereas performance 'floats' (rounding and smoothing of th e dental arcades) would adversely affect digestion, 8 mature horses free fr om dental correction for over a year were used. Five-day digestion trials w ere conducted before and 2 and 4 weeks after correction in all horses. Alth ough all horses had sharp points and minor premolar hooks, none had severe dental abnormalities. There were no significant differences found in appare nt digestion of dry matter, crude protein, neutral detergent fibre or acid detergent fibre relative to precorrection data or controls (uncorrected hor ses on same digestion trial), Apparent digestibility of crude protein and f ibre, however, was reduced if the occlusal angle of premolar 307 was greate r than 80 degrees relative to the vertical axis (flattened), It should be r ecommended that regular dental correction be continued. However, if only sm all points and hooks are present, correction will not significantly improve digestion. Performance floating does not adversely affect digestion 2-4 we eks after the procedure is performed. Alterations in molar occlusal surface angle may affect digestibility of protein and fibre.