Chicken with tail down but otherwise seems fine

[Archer]

I'm stumped. Notice it last Sunday, so it's been 3 days. Took her in and gave her a warm bath for 20 min., feed her a little olive oil and felt around the vent. At this point ruling out egg bound. Can't see anything else. She is pooping, eating and drinking and not lethargic. Does anyone have any ideas? She's about a year old.

 

[ChickensAreSweet]

I have read threads before about tail down being the only sign something was wrong. Unfortunately I don't know the cause. You might try searching BYC for "tail down" to see if you can find similar threads until someone responds.