Chicken sick

[Archulettav]

I lost my second chicken yesterday… They have poopy butt And Feathers are all gone around its tail… I’ve used it Damascus earth I don’t see mites or fleas
Any suggestions? The red star chickens

 

[Bird_Lover_17]

@Wyorp Rock @Eggcessive

 

[Wyorp Rock]

I lost my second chicken yesterday… They have poopy butt And Feathers are all gone around its tail… I’ve used it Damascus earth I don’t see mites or fleas
Any suggestions? The red star chickens

Welcome To BYC

How old are your birds and what do you feed?
Do you have a rooster?
Where are you located in the world?
How much space in the coop/run do you have?
Is this hen laying eggs consistently, any issues with egg quality?

Feather loss looks to be from picking and/or mating. Observe your flock's behavior to see what's happening there.
I would consider worming or getting a fecal float to check for worms. DE is not that effective for lice/mites, but added to dust bathing areas, it may help. If you do see bugs, I suggest you use a permethrin based poultry spray or dust.
Check to make sure her crop is emptying overnight.
Red Stars are production birds, so they may start having some reproductive issues that are common in laying hens.