One good thing about having snow is that there are lots of hoof prints to look at - an endless source of fascination for a hoof-anorak like me! Often, the snow means that shod horses can't venture out, because its just too dangerous, but the snowfall last Friday was so light that for once you could see the barefoot and shod horses' hoofprints side by side.
The close-up shots make the difference in how hooves load crystal clear, and also highlights the factors I blogged about earlier in the week.
The weight of the shod horse has been taken peripherally, by the rim of the hoof; the frog has taken almost no weight and has barely touched the ground.
By contrast, the weight of the barefoot horse has been taken caudally, by the heel and frog, with the hoof wall sharing the load as the limb moves towards breakover.
If you think about the weight of the horse's body, held up by the bony column of the leg, its easy to imagine which loading option gives greater stability, support and shock absorption. Its also very clear how much smaller the loading area is for the shod foot, putting a much greater strain on the edge of the hoof. The barefoot horse, by contrast, has a huge surface area over which to spread the load.
These photos really illustrate the effect shoes/barefoot may have on bone stimulus, I think - as I posted on the 2 blogs earlier this week - http://rockleyfarm.blogspot.com/2010/02/stress-shielding-more-about-bones-and.html and http://rockleyfarm.blogspot.com/2010/02/reversing-navicular-bone-damage.html
FWIW, I am not taking bets as to which horse has the healthier bones, even though the barefoot print is from a horse is who is 25 years old!