spots on comb

[kens147]

my roosters have black spots on there comb is because of frostbite

 

[ChickBond 007]

Could be from fighting/pecking in the coop. Frostbite turns white before it turns black.

 

[jenjscott]

Also, depending on the type of comb, it will affect the smaller pointed ends first. If they are spread around on the comb, and wattles, you may be looking at pox.