
Hi. I’m sorry your girl is having a hard time.
That lump looks like a localized abscess to me, considering she recently had that injury just behind it’s location.
Does it feel firm?
I would want to lance that, to see if you can empty it.
Remember chicken “pus” is often a firm waxy texture, not usually runny or gooey like an abscess in a mammal.
I’m sorry to say that DE is not effective in killing an active case of external parasites.
As the above poster mentioned, you can use ivermectin, but for ease of use and low cost I would recommend a horse fly or stable spray at your local feed store.
The active ingredient is
Permethrin 0.50%
Spray lightly under each wing, around vent, on neck. For her head, I’d spray a cotton ball and dab her head so it doesn’t drip into her eyes.
It works really well and costs no more than $10. Re-treat In a week.
Clean coop and nesting boxes. Bag and dispose of old bedding. Spray the coop down, don’t forget the topside and underneath of the roost!
Repeat in a week.
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