Motherhen, your post has caught my attention. Would you please, when you have a few minutes, change your avatar to include your location, B.C. is a very big place, and how about making a formal introduction to yourself in that forum, so we can know a little more about you. This is not to be nosey (well, I kind of am
, smiling) but this will help out so much when you are asking questions. You are an inquisitive type of person and this is a wonderful thing. Knowledge is powerful and you are asking good stuff for surely. So take that time. Where in BC do you live, especially. You speak of rats. I am thinking you are in the coastal part of the province, are you near to the ocean.? If you are, then you can have some pretty powerfully big rats. We lived in Maple Ridge for the past 25 years (and have always lived in southern coastal BC) and I KNOW for a freaky fact how big those rats can be and those rats LOVE to eat chicken food and will even take eggs. A friend of mine recently, that lives in Langley was telling me that he thought the chickens were eating eggs, and he was distressed. We talked about it and it really appeared that the rats might have been taking the eggs, there in the morning, gone in the afternoon. My experience with chickens eating eggs is very, very limited, never had an egg eater, but I understand things. Most often, chicken do not eat their own eggs unless that egg is broken. So I told him to look for rats. He said they had lots. Well, I told him, say no more. Get rid of the frickin' rats and the eggs will return. The eggs returned.
Living here in the north Okanagan (moved up here from Maple Ridge June 15 2010) there are not rats, but mice, lots of mice. They are their own little problem, but not the hideous rat things. Back on the coast we had horrible rat problems and I got fed up with it. Tired of the crap everywhere, the damage, seeing them pop their ugly heads out from under the barns as the horses would eat the grains in the stall, look outside the door and grain fell to the ground. The rats would line up under the barn and at feeding station you could see them poke their heads out, go back under, poke their heads out, get more grain that had fallen. Still clearly remember this line up of rats. I brought out the big guns and eradicated them. It was ruthless and I did this a couple of times a year. By the time we had moved from that town, there was not a single rat on my property. Not to say that the rats probably would have migrated over from the neighbours, she didn't believe in rat control. I am a freak about rat control.
I think my point I am trying to make is rats are bad. And I wouldn't doubt that you have a bad rat problem, are you in the city limits, if so, then they would be even worse, perhaps water rats that have moved inland, smiling. I think that rats could cause damage to chickens. I am not positive of this, but perhaps the rats are biting the birds (do rats do this? anyone know?) and then the birds pick at blood spots from rat bits? I don't know. I am just giving you some scenarios to help you out. You need to try and rat proof your henhouse, if you can, seriously....big job, but I think things would be so much nicer for the chickens and maybe the rats are biting the girls and causing them to pick each other, sigh. Wish there was more help I could offer, but I just think that if you listen, maybe things will get better. There will be others that will reply to you and hopefully help you to get to the bottom of this. Good luck, and do have a most wonderful day, CynthiaM.