When standing
When walking

What are you filling out, a test? You were asking a bunch of questions like this yesterday too.
Look it up yourself- its easily findable via google.

When standing, u can not always detect lameness. If its bad enough just standing, the horse may avoid putting weight on that particular foot.

When walking, u will notice ur horse will be stiff. If its one foot in particular that is bothering it, it will have a limp. Sometimes u have to watch carefully because it will be slightly. Also, if a horse bobs its head up & down when its moving, that generally means pain.

If u r try to look for lameness, have someone else walk ur horse so u can stand back at a distance & observe.

Depending upon just how LAME the horse is, when standing you will notice that one leg is ''POINTING'' more forward than the other (Unless it is something like founder where the horse will CAMP (Have both front legs stretched forward.).

As for movement, you can lead the horse and notice that as it steps on one particular leg the head will make a downward movement 'cause the leg hurts! In navicular or founder, turning the horse will cause the horse to stumble.

Lame on the forehand:

Try picking up each front leg. If he usually picks it up & does not now he may be lame. Feel each leg for swelling on the leg & hoof. Compare each leg to see which is hotter. Your horse will rock back onto his hind legs in attempt to keep as much weight off of his front legs. EH may run a temperature, sweat or have rapid and/or shallow breathing. The affected area will be hot & a strong pulse will be felt in the digital artery which is located above the fetlock joint. He may even lie down if it is severe.

If it is undetectable while standing, trot ur horse & have an experienced horseman watch for the following signs.
*Head bobbing( if unusual to the horse)
*Slamming down of healthy hoof in order to keep weight off of lame hoof(limping)
* Refusal to go forward

Treatment:
First, call the vet. While u r waiting, try these treatments to alleviate pain.

*Run cold water over the area for 15 minutes & repeat hourly
*Walk ur horse for 15 minutes at a time to keep blood moving
*Remove grain
*Try a poultice to remove swelling. Simply wash it off when the vet arrives

Good Luck!

when you trot it back and forth. so , yes walking

when standing the horse will favor that same leg, even after you tuen it around.
When walking, anything in the hines will be a limp, anything up front is read through their neck posture, usually a bob of the head when the affected leg hits the ground.

just depends..

It depends on the lameness but a horse with navicular syndrome may stand & point the toe of one hoof to take the weight off the heel. You can pick up the hoof & try putting pressure to see if he/she reacts or look to see if one hoof is cracked or worn in an unusual way. My horse wore his toe down a lot more than normal when he was lame. At the walk see if the horse is moving differently or if the strides r short. If u ask the horse to trot, look to see if he bobs his head when he puts weight on a certain hoof or moves stiffly. You can also look at the horse is face- if a horse is really in pain u can tell if they pin their ears when u ask them to move out or sometimes their eyes look dull or tuned out. If ur mounted u can usually feel the lameness at the trot & if u can not feel it easily posting on the wrong diagonal can make it feel obvious. If all else fails u can call a vet & they can do radiographs, ultrasounds & nerve blocks to pin point a lameness. l hope that helps.