I notice that sometimes my 3 day old chicks have some poop stuck to their bottoms. I have been wiping it off I went to tidy up one little girl tonight and I just can't get it off. It has dried there. It isn't runny or sticky. It just looks like normal poop that dried there. Should I just let nature do it's thing, try washing it off again with a wet cloth, or is it pasty butt?