question about teeth......

my 3 1/2 year old star, has had a really rough time this summer with wieght, some thing got the best of me tonight and so I checked his teeth, the teeth that I have colored in look rotten and not like the other plus he has bruising on his bottom gum (about loonie size) ....his uppers all seem to be fine but his bottom teeth really bother me.......

Right he is on a mash of about 11 pounds of mare and foal feed and all the hay he can eat, our vet will be by in a few days but I just can't figure it out........

If he is 3.5 years old and those are his baby teeth, then they are probably ready to fall out and grow adult teeth. The first set in the middle will fall out at 2.5 years, the second set(the ones you highlighted) will fall out around 3.5 years, and the next set out at 4.5 years, this goes for the top and bottom teeth. So if they look like the gums are raw and maybe brusing a little bit and the teeth look dead, I would say they are gettin ready to fall out.