Mites or just a poopy butt?

[Summerbirds]

I have one chicken with pretty dirty butt feathers, I had assumed it was just that until today she wouldn’t leave the coop and overall didn’t seem so great. After a little reading I’m thinking it could be mites? I haven’t noticed bugs on her, but I have seen a few around the coop. My other hens don’t seem to be affected either. She is about 3 or 4 years old. Here are some pictures.


Could this be mites?

 

[coach723]

Do you know when she last laid? Does the abdomen feel bloated at all, below the vent between the legs? At 4 or 5 years old reproductive problems are not uncommon, which will often cause dirty rears because they have trouble pushing droppings out. Some birds have what is sometimes called 'lazy cloaca's" and they just don't push the droppings out as hard, and they will have dirtier butts. Have your birds ever been wormed or had a fecal done? Internal parasites can cause runnier droppings and dirty butts. With dirty vent feathers you do need to watch for flystrike, as that can be serious and even fatal, the flies will lay eggs in the droppings and the hatched larvae (maggots) will feed on the chicken. The feathers below the vent can be trimmed back with some small scissors, which may help it stay cleaner.
And this link will help with the ID of lice/mites:
https://the-chicken-chick.com/poultry-lice-and-mites-identification/

 

[Summerbirds]

She last laid an egg yesterday morning, I will trim her feathers and check to see if she’s bloated. I will also read up on lice/mites.

 

[Summerbirds]

I forgot to mention deworming, this hen has never been dewormed but I have dewormed other hens in my flock and still have the medication.

 

[coach723]

Since she laid yesterday, then it's not likely a reproductive problem. So lazy cloaca (seems to be more common in heavy birds), parasites, dietary cause (any changes in diet?) or drinking lots of water could be the cause.

 

[Summerbirds]

No change in diet, although there’s a chance she got into the compost. It’s possible she snuck a few bites of my other chickens’ feed, but nothing major. It’s been rather hot here, so I wouldn’t be surprised she’s drinking more water.

I cleaned out my coop, I didn’t notice any bugs or anything out of the norm. I’ll deworm her too.