There's a new Icelandic Horse study that has to do with age of maturation and bone fusion.
It's Conclusion states: "The Icelandic horse appears to have similar radiographic closure times for most of the growth plates of its limbs as reported for large new breeds of horses developed during the past few centuries. It thus appears that different breeding goals and the intensity of breeding have not altered the length of the growth period in horses. Instead, it can be assumed that the pristine and relatively small Icelandic horse has a slower rate of growth. The appendicular skeleton of Icelandic horses has completed its bone growth in length at approximately 3 years of age, and therefore may be able to enter training at this time." It appears to be saying that the growth plates close at a time similar to other horse breeds, but then they say it has a slower rate of growth; and that they can be ridden earlier. Also, a problem with the study is that they only measured appendages (legs) and did not consider the spinal processes. Judy http://iceryder.net http://clickryder.com
