When Uni was a puppy she did get poop stuck in her butt constantly. I think it was bad food choices that were making her poops not hard enough. If they are hard they usually kind of fall out, and not very sticky. Occasionally though she will ingest a hair (usually mine or bf's

) and if she poops it may only part way come out and the poop will hang there. You can NOT just pull out the hair, you can do major damage. Carefully find the hair and cut it, leave the rest inside, and the next time they poop it will come out. Whenever she has some cling-ons she freezes anyway, so she makes it easy for me to cut out the hair.