|A near perfect frog, from a hind hoof.|
Correct movement = heel first landings = the force of the hoof hitting the ground being dissipated throughout the structures designed to do just that, limiting concussion.
The frog should look plump, open, flat and healthy. It should be wide at the heels. The central sulcus should look like someone has pressed their thumb into pliable putty, not look like a deep crevice. It should be free of thrush, and have passive contact with the ground in the stationary hoof. On soft ground (where the hoof would sink into the ground when loaded) the frog should be further away from the ground than on hard ground, where the frog is normally at heel height
|The frog should take up 2/3 of the hoof|
The frog should barely be trimmed at all. The only trimming a frog would need in most circumstances is to open up any areas that thrush would be hiding under.
|The frog should NEVER be trimmed like this, no matter how pretty that looks!|
|Frog has become too passive due to thrush infection (looks like it is clearing up though)|
|Severely contracted hoof and frog.|
|Top is a fairly normal hoof with frog having passive ground contact. Bottom is a contracted hoof with the frog suspended out of contact with the ground unless the ground was very soft.|
So consider the frog when trimming - leave it alone unless there is thrush present, then take the bare minimum you can. Keep it clean, and in passive contact with the ground. Most of all, trim for heel first landings! If a horse is landing heel first, the frog will pretty much look after itself.