Rings on the hooves only appear after a horse has actually foundered. A horse can have laminitic episodes without foundering.
OK, sounds like you have a different definition to me. I think of them interchangeably these days, laminitis being the more 'correct' term & 'founder' being the 'lay' term. There are various degrees of laminitis & laminitic damage. It appears you may be thinking of laminitis as the initial inflammation and founder as the mechanical damage that can result from it? - That happens to be the way I used to classify the terms.
Founder means that the horse's feet have been damaged. The rings seen on a foundered horse's feet indicate that the hoof wall attachment to the inner hoof structures is damaged. It usually means that there has been some rotation of the Third Phalanx because of this damage. ...
Further, if you look at those rings, you will see that they are closer at the toe and wider apart at the heel. This proves to the unbelievers that the heels are growing much faster than the toes.
OK, I think our differences are partly another difference in definition perhaps
. Laminitic 'episodes', even 'low grade', unnoticed ones generally cause enough damage as to cause rings/ridges. Depending on the severity, length of the 'episode', mechanics at play, etc, this may be all the damage there is to show. Laminitis/founder doesn't necessarily mean P3 has 'rotated' or 'dropped' within the capsule. Generally it seems that it takes chronic, long term or untreated lami to lead to rotation & sinking. Not sure how much compromised blood supply comes into it, but it appears the lamellar damage is largely to do with toxins &/or insulin in the blood.
It does appear that chronic laminitic hooves can grow 'fast forward', but I'm not sure that this is due to slower growth at the toe, but when mechanical forces allow it(ie. toe walls are loaded when damaged), the growth that does occur becomes more sort of buckled at the toes. I disagree that the heels are healthy while the toes aren't, just that the laminae under frog horn isn't the same or under the same sort of mechanical forces.
Also disagree with the use of heart bars generally or that they 'put' majority of the horse's weight on the heels... but that's another subject really
I think you misunderstood my comments about starchy feeds. What I said was "nothing to do with weight or workload. It does have to do with how it's fed though I think" While I think *appropriate & good feeding amounts/practices* are far safer, so very few horses fed as such suffer any great issues from this sort of diet, it *can* be very problematic and so many people don't understand enough about horse's digestion & proper feeding to feed it safely.