WHAT’S NEW in the veterinary world?
Peter Green MRCVS reviews the latest research into bits
BITS have been used to control and steer horses for around 6,000 years, and the majority of horses still wear bits in their mouths for riding, driving and working. Modern bits vary in severity and, thankfully, few horses are fitted with the horrendously long curb arms or sharp twisted mouthpieces worn by battle horses in times gone by.
Riders and governing bodies are much more aware that bits – or, more accurately, the incorrect use of bits – can cause damage to the horse’s mouth. Most riders would now be concerned if they were told that they were inflicting suffering on their horse because of the bit.
The balance is tricky, because bits and bridles work by exerting pressure on a part of the horse’s head. It may be pressure on the bars of the jaw and corners of the mouth through a snaffle, pressure on the bars and chin through a curb chain, or pressure on the nose through the noseband; even pressure on the poll through a gag. But pressure should not cause injury.
Researchers in Denmark examined every one of the
342 horses and ponies taking part in the Danish national championship competitions before they competed in the 2020/21 season. These were elite eventing, dressage and showjumping horses and ponies.
They were all vet-checked before the competitions, including a careful examination of their mouths. The presence of scarring, ulcers and fissures on the bars, in the mouth and on the corners of the lips were recorded, together with the condition of the teeth. Details of rider, trainer and competition record were noted.
CAUSE FOR CONCERN
THE results were sobering: 30% of the horses and ponies had scarring or active injury to their mouths. The most common site of a problem was the corners of the mouth, where ulcers were discovered on either the outside or inside of the lips. If an ulcer was found on one side of the mouth, the results showed that there was likely to be an ulcer on the other side as well.
The researchers were surprised to find no correlation between ulcers in the corners of the mouth and sharp hooks on the first upper premolar teeth.
In racehorses this is a recognised problem, which is thought to be because they race with their heads straight out to maximise air intake – pressure on the jointed racing snaffle pushes the sides of the mouth against the teeth. Dressage, eventing and showjumping horses compete with their heads lower, so the pressure is different.
There were two other significant findings in the Danish study. When just the records of the 100 ponies were studied, the prevalence of mouth injuries was linked to the size and success of the pony and the age of the rider. In the under-16 148cm (14.2hh) pony dressage classes, 26% of the ponies had bit ulcers in 2020, compared with 0% in the under-13 130cm (12.2hh) class. The older riders on the bigger, more successful ponies were causing more mouth injuries than the younger riders on the smaller ponies.
The presence of these mouth ulcers was linked to certain trainers, with some individual trainers having more ponies under them with bit injuries than others, suggesting issues with the training regime.
The federation was firm about the problem, and every pony discovered with a bit injury before competing in 2020 was sent home. In 2021 many of the same ponies made it to the national championships again and, guess what? Only one pony had a current bit injury!
Ulcers, fissures and sores caused by the bit are not inevitable. Changes in riding technique, more sensitive use of the hands and more careful instruction by trainers can make a big difference.