Sorry I have not followed closely. Where is the lump? I did have a chicken who had a mass that the avian vet could feel. We put her on hormones to make her stop laying, because it seemed like the laying was going to kill her. I am absolutely, 100% certain that the hormone implants extended her life. She definitely seemed to be feeling better on the hormones and occasional anti-inflammatories and antibiotics. However, ultimately she had advanced ovarian cancer that had spread to multiple organs, including thickening her abdominal wall. She definitely seemed to have some good life in there, but I think it took it too far and extended her life too long. Hard leason learned at the expense of a beloved feathered friend.
I still seek Avian veterinary care when I think it is needed, but when the prognosis is looking like they are likely to continue suffering and worsening, I am more likely to opt for euthanasia now. Having said that, I recently had a 5 1/2 year old hen with a very swollen abdomen and slow crop, who I thought was likely dying. Instead of having her euthanized, I drained her coelom myself and helped her with her crop for a couple weeks. As of today, het behavior is almost completely back to normal. Point being, I do not opt for euthanasia unless I feel pretty certain the bird will continue declining and suffer, even with intervention,
Unfortunately, outside of molt and older birds in winter, almost any hen in my care who stopped laying on her own ended up having a serious condition (cancer, egg yolk peritonitis, orfatty liver). Please do note the exception of the alpha hen, Bridge. She will be seven at the end of February. She stopped laying a few years back, and still seems like the one of the most robust, healthy birds. The only time she has ever, ever looked like she wasn’t feeling well was when she had a molt coming on, or she was in molt. In her case, I consider the stop in production a blessing.
Sorry about rambling on and not actually offering much advice nor wisdom. I can really only share my experience and perspective, and I’ve only been at it almost 7 years.
Since I haven’t posted photos in a while, here are some of the birds mentioned in this post:
Bridge, the current alpha and only survivor of the original four
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Lucky, who recently responded to being drained and having her crop worked
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Margo, the alpha before Bridge, who I euthanized myself when she was unresponsive, but was dying of egg yolk peritonitis gone septic per necropsy at UC Davis
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Ruby, whose life I prolong too long and died of cancer per necropsy at UC Davis
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Rusty, who died of egg yolk peritonitis at the tender age of 18 months - diagnosed by avian vet
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Bagheera, who died of fatty liver per necropsy at UC Davis
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Dorothy, who suspectedly died (young) of egg yolk peritonitis gone septic after a year of soft egg shells
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Ester, who I had euthanized and was dying (young) of cancer per necropsy at UC Davis
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Sunshine, who died (young) of fatty liver per necropsy at UC Davis
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Cashew, who I recently had euthanized at about 5 1/2, because the avian vet, who thought cancer was likely, was unable to help her and she was declining
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