I don't know who it was on this forum who recommended Vaseline for pasty butt awhile ago, but it works FANTASTIC! After cleaning the pasty butt with a little warm water to soften it off, I patted the area dry and, with a Q-tip, applied a little bit of Vaseline/petroleum jelly on the chick's vent. Not too much where it was gooey, but enough so the poop wouldn't stick. I did this on four of my chicks and have not had one unresolved pasty butt since! If there was a little poop on the chick's fluff, I tried to get it off, but didn't worry about it too much... I just made sure that the vent was not blocked. I did reapply the following day to vents as a precaution. I'm hoping by sharing this wonderful tidbit of info again that some little chick's butt will be saved.
Again, giving credit where credit is due, thank you to the kind BYC member who originally suggested this!! 

