Effect of 'tongue tie' use on racing performance of thoroughbreds in the United Kingdom.

Reasons For Performing Study: There is contradictory published evidence on the potential efficacy of 'tongue ties' (TTs) for treatment of intermittent dorsal displacement of the soft palate (DDSP) in racehorses.

Objectives: To evaluate the effect of TTs on racing performance in Thoroughbred racehorses in the U.K. using a retrospective cohort study.

Methods: Data on individual horses' lifetime racing performance and TT use were retrieved from the Racing Post Online Database. Exposed cases were horses that ran with a TT in randomly chosen race meetings on one of 60 randomly chosen dates from 2001-2003. Unexposed (control) horses were matched to each exposed horse. Various measures of racing performance were analysed both within and between exposed and unexposed groups. Subsets of exposed horses that ran for 3 or 5 consecutive starts wearing TTs and their matched controls were analysed separately to examine the effect of repeated TT use.

Results: The inclusion criteria were fulfilled by 108 horses. The odds ratio for 'improvement' in race earnings between exposed and unexposed horses was 1.85 for horses that ran at least once with a TT, and 3.60 and 4.24, respectively, for horses that ran in 3 or 5 consecutive races wearing a TT. After instigation of TT use, horses that ran in 3 or 5 consecutive races wearing a TT had a significant increase in earnings when they ran wearing a TT compared to their pre-TT races.

Conclusions And Potential Relevance: The use of a TT appears to have a beneficial effect on racing performance in a selected population of Thoroughbred racehorses.