Q: We are considering
purchasing a pony who is perfect in every way, aside from her parrot mouth. We
have been told that this occurred due to an accident when she was a foal, but
others have since said that this condition can only be caused by genetic
factors. What are its implications, both in terms of management and ridden
issues? We were thinking of breeding from her, but could this condition be
handed down to her offspring?
A: A 'parrot mouth' describes a horse whose lower jaw
is shorter than the upper jaw. In a severe parrot mouth, the upper incisors (teeth
at the very front of the mouth) will overhang the lower jaw, becoming
increasingly longer as they continue to erupt, with nothing
opposing them to wear them down. In turn, the lower incisors will grow up into the
hard palate (roof of the mouth) and start to rub, causing discomfort. A
horse with a severe parrot
mouth may have difficulty grazing on short grass because the front incisors will
reach the ground first, preventing the bottom ones from cropping the grass.
A parrot mouth can also affect a horse's cheek teeth, as the upper cheek teeth may sit further forward than the lower ones. If it is not corrected, this misalignment can lead to a painful hook forming on either the upper or lower teeth, which will eventually prevent normal movement of the mouth during eating. In a less severe parrot mouth, although the upper jaw still protrudes over the lower, the incisors and cheek teeth have a greater degree of contact, leading to fewer problems.
Parrot mouths are commonly considered genetic defects that are present at birth, and for this reason it is usually inadvisable to breed from horses with this condition.
For all forms of parrot mouths, regular dental attention is the key to ensuring that it does not cause the horse any problems. Your equine dental technician can reduce the unworn teeth, preventing them from becoming excessively long and causing the problems outlined above. This will allow the horse to lead a normal life. If this horse receives regular dental care - and I cannot stress enough how important that is for a horse with this condition - there is no reason why it should effect your riding in any way.