Improving the predictability of performance by prerace detection of dorsalmetacarpal disease in Thoroughbred racehorses

Objective To determine the prevalence of dorsal metacarpal disease in 2-yea r-old Thoroughbred horses by prerace inspection and to evaluate the effecti veness of a dorsal metacarpal disease detection program on the predictabili ty of race performance (finishing in the order predicted by punters) and th e distance between the first- and last-placed horse in a field. Design A retrospective study using client-owned horses. Methods A program of prerace detection of dorsal metacarpal disease using d igital palpation of the dorsal aspect of the third metacarpal bone of both forelimbs of 2-year-oid Thoroughbreds racing at Ascot racecourse was instit uted by the Western Australian Turf Club in December 1995. Horses that had significant pain reaction to digital palpation were considered to have pain due to dorsal metacarpal disease, withdrawn from that day's race and not p ermitted to race for 6 weeks. The race records of all 2-year-old Thoroughbr eds racing at Ascot racecourse from December 1993 until December 1995 were compared with the race results from December 1995 until March 1997, after i nitiation of the dorsal metacarpal disease detection program. Results After initiation of the program, horses were racing more predictabl y over 1100 m (P = 2.09) and 1200 m (P = 3.48). These horses finished close r to the winner over 1100 m (P = 3.39) and over 1200 m (P = 3.13). In 1000 m races, the trend for horses to race more predictably (P = 1.07) and for t here to be less distance between first and last (P = 1.72) was not statisti cally significant. Conclusions The program of prerace digital palpation for dorsal metacarpal disease was considered to be beneficial in 2-year-old Thoroughbreds racing over 1100 m and 1200 m, in that they raced more predictably.