We had a problem with this initially. The pasting quit when we adjusted the heat lamp's ht. above top of brooder so that the radiant heat wasn't as intense (right temp. but somewhat like the difference between standing in the direct sunlight), or in the shade on a 95° day - brooder should be big enough to allow all to move into and out of direct light. Sides of brooder (depending on what you are using) can be draped with towels, or just place a sheet under it and fold up over sides to adjust for temp. and avoid drafts (this allows for light to be moved away from `butts' without impacting temp).
We crushed dried poop (without pullling) with small, wide faced pliers (get the worst), then used a drop of Dawn dishwashing detergent, a couple drops of aloe vera with a bit of water and worked away the actual blockage of cloaca, without messing with trying to remove anything `stuck' to the the skin around the vent, with our fingers - gently (healed up pretty quick).
We crushed dried poop (without pullling) with small, wide faced pliers (get the worst), then used a drop of Dawn dishwashing detergent, a couple drops of aloe vera with a bit of water and worked away the actual blockage of cloaca, without messing with trying to remove anything `stuck' to the the skin around the vent, with our fingers - gently (healed up pretty quick).