Equine, I love the pics of the Fresian, they are a beautiful breed.

Ok YLL., a couple more answers for you
A Galvayne groove is a groove in the horses tooth that helps you tell the age of the horse.
A parrot-mouth is an overbite, when the upper teeth stick out over the lower teeth, the teeth will not have a normal wear pattern making it difficult or impossible to tell the age of the horse.
That last photo is of something an Equine Dentist would use to hold the mouth open, I think it begins with an S, I can't remember the name.