I have several different breeds of hens. Some of these have no feathers around their vent/behind while some do. I am perplexed about this. Does anyone have any idea why some do and some don't? What is this caused by? Is there anything I can do for those that don't? I also have some hens who are eating eggs. I have tried golf balls in the nesting boxes and also collecting the eggs more frequently, but am still finding 1-3 eggs broken/cracked. Any suggestions would be most appreciated. Thank You!!