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Published on: September 19, 2011
Preliminary study of jointed snaffle vs. crossunder bitless bridles: quantified comparison of behaviour in four
1Cummings School of Veterinary Medicine, Tufts University, 200 Westboro Road, North Grafton, Massachusetts 01536, USA.
Abstract:
The study tested the null hypothesis that if a horse is ridden in a snaffle bridle and then a crossunder bitless bridle, there will be no change in its behaviour. It was predicted that there would be change and that behaviour would improve when bitless. Four horses, none of which had ever been ridden in a crossunder bitless bridle, were ridden through two 4 min, exercise tests, first bitted then bitless. An independent judge marked the 27 phases of each test on a 10 point scale and comments and scores were recorded on a video soundtrack. The results refuted the null hypothesis and upheld the predictions. Mean score, when bitted, was 37%; and through the first 4 min of being bitless, 64%. A binomial probability distribution suggested that the results were significantly different from random effects. All 4 horses accepted the crossunder bitless bridle without hesitation. Further studies are warranted and it is hoped that others will build on this new field of investigation. The authors are of the opinion that the bit can be a welfare and safety problem for both horse and horseman. Equestrian organisations that currently mandate use of the bit for competitions are urged to review their rules.

