Can this be serious?

I was practicing picking up Thunder's feet yesterday and I saw that he had clipped the pad part above the hoof on the left front. It's a pretty big chunk that looks like a flap. I couldnt really tell if he was favoring it, but he was acting very lazy yesterday and almost refused to trot when we changed directions going left and refused to lounge left. The vet is coming out tuesday for shots, so I was going to have him look at it, but do you think it will be ok until then?? It's not bleeding and when pressure is applied, it doesnt bother him. It does have quite a bit of mud in it.

Sounds fine, just clean it out.

I agree just clean it out really good. You could take a damp sponge and clean out all the dirt really well. Then since the vet is coming out I would just ask him/her if it's anything serious. It most likely isn't anything but who knows.

Yeah, I also agree- give it a good cleaning. :)

Yep, cleaning it up is the first step. Then once you get it clean and dry go ahead and bandage it--this will probably be easiest to accomplish by wrapping the foot as though you were dealing with an abcess. Then restrict activity as much as possible to allow it to heal better and more quickly. That area moves alot during walking and that will slow healing and promote proud flesh.

It doesnt sound like a serious problem. I would keep an eye on it and keep him on a dry surface to help keep it clean. Just have your vet take a look when he comes out.

I was told by someone that I can get those boot things (sorry for the slang lol) to prevent this from happening. Good or bad idea?? Or is there anything I can do other than the boots?

By "pad" do you mean the bulb? If so, he may of forged. Bell boots would certainly help.