Now first, let's talk about the stacks themselves. Most people in the industry call them "pads" or a "package." I call them "stacks" because they are truly are that--stacks of pads made of leather, plastic, or aluminum or any combo thereof that are usually used for therapuedic reasons to protect the hoof. For example, I used to own a mare that wore pads on her front feet underneath her shoe. She used to be prone to stone bruises, so the pads protected her feet from this problem. Eventually my farrier found a hoof supplement that worked wonders for her, so she didn't have to wear them anymore.
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Now, there is nothing illegal about horses wearing pads. And it's not just the TWH industry that does it--Hackneys and Saddlebreds also wear pads and what they call "wedges." The wedges aren't nearly as tall as the TWH packages are. In 1986, a controlled study by the Auburn University (and I mean controlled by the TWH show industry) was done to see if the packages "hurt" the horses. They found that horses with packages are not under any stress and that a horse can wear chains around its pasterns up to 6 ozs without it causing pain. Of course, this was done without the horses being sored, and the horses used in the control were not studied over the long term as to whether or not it was a problem for them over time. The study did find that there is a higher incidence of thrush and laminitis in stacked horses, but that fact is usually hushed up. Of course, this study has never been published publically since the sore horse industry wants to continue to just quote only the good things that the study found, not the bad things. Click here for a good explanation of what the study found that you will not hear from the TWH show industry.
Many times you will be told by sore horse and stacked horse supporters that "it's no different than you wearing high heels." But there's a catch to that: when a woman (or man--hey, it happens) wears high heels, she can come home and take those high heels off. A TWH does not get to do that. He wears his pads 24/7 until he is retired from the show ring. He'll get them taken off for another trimming or to "fix" him in various ways to cause pain to the bottom of his foot for showing, but otherwise he wears them all the time.
Now, I don't know about you, but when I wear high heels, my feet hurt after just a couple of hours. So imagine being forced to wear them 24/7 AND you're a creature that does not sit or lie down for long periods--you stand for a good 23 of the 24 hours in a day.
What sparked this post was this article sent to me by a fellow blogger: The Quest to Conquer Laminitis. Most importantly, we can look at this chart: How Hoof Angle Affects Blood Flow. She said she sent it to me because the photos reminded her of the angles of a stacked horse's hooves. The vet who designed this machine in the photos is trying to understand how the blood flow in the hoof is working, because we know decreased blood flow causes laminitis. If he does a venogram of the horse's hoof, he can look at how the veins are working and be able to shoe and/or trim the horse correctly to increase the blood flow. Note that the photographs are of a sound, non-laminitic horse. When his hoof is tipped forward at 15 degrees, "there is increased loading of the heels and subsequently less blood flow in the bulbar vessels." So what does this mean? It means that the heel of the coffin bone is taking more of the weight while the blood flow is being cut off to the bulb part of the pastern.
Look familiar? The angle of the hoof in the photo of the stacked horse above is similar to the angle in the above linked chart. Plus, the horse in the photo has a longer toe and lower heel that the horse in the chart who has a normally trimmed hoof. This means the coffin bone is pointed in a more downward straight position for the stacked horse than the normally trimmed horse, most likely putting more stress on the bone itself. Now think about how the stacked horse is standing this way for 24/7. How in the world can a horse not be affected by this over the long term?
I think that this is something that the Sound Horse Conference and other groups can use to help end this grotesque image of our wonderful breed. If we can prove that yes, stacks over the long term are damaging, then perhaps we can get them included in the HPA. Maybe there is hope for an end to this after all....