Poorly Chicken

[Milims]

On of out chickens has lost all the feathers off her bottom which now looks very red and swolen and (sorry to be graphic) her poo is sticking to her - almost as if she's constipated. Does anyone know what could be wrong? He tail is all droopy and her comb is dark pink rather than red

[theabsinthefairy]

When is the last time she laid - she could have a stuck egg, if she has caused the damage to her bottom herself and if she is wandering around with her tail down.