I know how to do this, but there is no 100% accurate way...at best aging is a guestimate.
What sort of info are you looking for so I can maybe direct you to a source?
S
Oh, there's a really good CD Rom called Ageing a Horse by Dr Derek Knottenbelt produced by the University of Liverpool that would help you. It's interactive, has pictures, animations of aging, and I used it to teach a class of BHS Stage 3 students how to age in one lecture (so pretty effective too!)
S
In almost everyway she looks a young horse the teeth tell a different tale in that the lower teeth protrude forwards suggesting she is 15 plus. Though I've always suspected this (it doesn't make it a problem what age she is), I am just interested in being able to date her age more accurately.
Once they're over ten, you look at a combination of factors - the angle of the teeth (which you mention), the shape of the surface of the tooth (increasingly triangular as horse gets older) and sometimes the Galvayne's groove (brown stained indentation starting on the upper corner incisor at around 10, gets halfway down the tooth at 15, reaches bottom at 20, approx.).
But teeth age faster with hard feed, sandy soils, shape of mouth, etc so not an exact science.
There's a Threshold picture book on Teeth and Aging too....
Hope this helps
S
Best way is to ask your vet or equine dentist. Though its only an estimate and not always accurate
when i had mine vetted the vet said he thought he was more a 2000 or 2001 foal (hiss passprt said 2003 which i knew he wasnt. i asked a different vet next time he was having his vaccinations and they said he was no younger than 5 but deff no older than 6... and he was nearly 8!