One of my Columbian Blacktail hens, Normal, has started to lie down on her tummy with her head tucked round into her feathers. She never used to lie down except with the others in the shade to preen, was always following me around. Here she is, before this started: And lying down as I described: She does this in broad daylight, not going to sleep or anything. It's not cold at all here, usually around 18 degrees C. The only other thing is I've noticed there seems to be a bulge coming out of her vent when it's relaxed, but couldn't get a picture of it. It holds it open, but when I look it seems completely normal. I might be imagining it. She also seems slightly off her food, but not overly. Otherwise she's perfectly healthy. I have no idea whether she's vaccinated against Marek's, but it's likely since she used to be one of the hens laying for Waitrose. I'd guess she's around three years old. So, is this something to worry about? Also, smears of what look like blood have been appearing on the eggs of another of the Blacktails. What can cause this? They seem to have gone now, but started about a month ago and went on for quite a while. I could see nothing wrong with the chicken.