Recurring sour crop help please!

[ChickenCanoe]

I don't want conflict. I want to help.
Before you said they wouldn't eat it, you didn't say that you fed any chicken feed so I figured you couldn't obtain any.
Birds that start healthy and have complete nutrition and big ventilation don't get sick unless there is a nearby flock with an avian viral or bacterial infection, they are all good.

 

[ChickenCanoe]

A lot of people talk about chickens eating grass. Grazers eat grass and can get most of their sustenance from that. Grazers include horses, cattle, bison, sheep, rabbits and grasshoppers.
Other herbivores are browsers(leaf eaters), frugivores(fruit eaters), granivores(seed eaters), nectivores(nectar eaters) et. al..
Chickens are none of those things, they are omnivores and may partake of any of those things but are also insectivores and carnivores.
So strictly grazers or granivores, they are not.

 

[tanchick]

Thanks will take note, always assumed grass was ok for them

 

[ChickenCanoe]

They will eat some grass if that is all that is available.
Many backyard keepers believe that they eat grass because they once had grassy lawns and now have bare areas. The chickens eat little of that grass. Most of the loss comes from scratching soil looking for bugs and seeds and digging up the grass in the process. Also soil compaction and incorporation of excess phosphorus in the soil from feces are huge contributors to the difficulty to re-establish greenery in a small space.
In some of my coops that don't free range, I rotate their foraging into a series of paddocks. I continually replant them with some of the forbs I mentioned in my first post. Interestingly,, when they get through with one paddock, all that is left standing are a few clumps of older turf type fescue and other coarse grasses.

 

[RumneyRoost]

I would definitely switch them to a feed designed for chickens. Balanced nutrition is extremely important. They may not "like" it, but they won't starve, they'll eat when they're hungry.

However, there are a variety of reasons that a chicken could develop sour crop. Some reasons are out of your control.

Does her crop empty at all? Is it just liquid? Or doughy? Has she passed any normal or solid poops? Or does she have diarrhea? Has she been laying?
Do your chickens have access to grit?

It's possible that she has an impaction somewhere that is causing things to back up.
It's possible that she could have picked up worms/parasites/virus from wild birds or from the soil.
It's possible that she lost the genetic lottery and developed some sort of cancer.
It's possible that a bout of stress knocked her GI out of whack and she's having trouble sorting things out.

Anyway. I would separate her for now. Withhold food so you can determine how much the crop is emptying, and so you can monitor her poops.
If the crop is sour you can treat with a cream containing miconazole or clotrimazole (for yeast infections in women), or get Nystatin from a vet. Avoid products with ethelyene glycol or benzyl alcohol.

A few weeks ago I had a hen with sour crop, still don't know why she developed it. I spoke with my vet and she recommended inserting a tube (similar to tube feeding) and using a syringe to draw up the yucky stuff. Then I flushed her crop with clean water and treated her with antifungals.
Here is a video on tube feeding.

I only gave her small amounts of soft food, and didn't let her eat again until her crop had emptied. Initially this took awhile. Everything was slow, and her crop was so stretched that it was below the opening to the proventriculus. I was concerned that I might be dealing with pendulous crop, but luckily things went back to normal.