Odd looking "growth on underside of chicken

[lolley]

Does anyone have any idea what this might be (please see photos), it's on the underside of the chicken, about 3" in front of the legs, it is soft to the touch, many thanks

 

[Wyorp Rock]

Welcome To BYC

To me it looks like a feather cyst, ingrown/broken feathers.

 

[Dontworrybequacky]

I discovered something similar on our funny little silkie hen about 10 days ago. I was looking for treatment advice but the threads were running very strong to "avian vet" which isn't helpful to a great number of us. A few posters did their own surgeries but we are in mud season so the stress of isolation would be our only other option for healing of the resulting surgical wound. The most helpful post said to give the chicken a chance by leaving it untreated and maybe it wouldn't develop into something worse. I took heart with this practical advice and started treating the spot nightly with Bannixx. To my surprise, after less than a week the fingernail sized core was gone and just slightly reddened skin was at the site which was alongside her keel. I continue to check her and apply a little Bannixx each evening. I wanted to share this small success because I was very concerned when I first found that evil looking lump. Wishing you fun and good health for your flock!