Multiple tumors- prognosis

[Wyorp Rock]

Thanks for the info. I run a closed flock except for this year (May) when I added some 4h chicks who we were told were vaccinated. We practiced full biosecurity between the chicks and our other flocks until after the fair ( which we missed due to a family emergency. She runs in a separate flock in which I have only added one blind rooster from my laying flock.
Her pen is fully enclosed so not even a sparrow can enter. I have had her since she hatched from my silkie hen who I have had for 2 years. How could either of those two diseases enter into our closed flock?

I will probably end up culling her but want to make sure I take precautions to protect my flock. This is exactly why I have been working towards a self sufficient flock.

I do recommend that you have her tested if you cull her. It could be a number of things, but the testing will give you piece of mind and you can be prepared if it does happen to be a contagious illness. Marek's vaccine prevents the formation of tumors, but does not prevent infection from the virus. If she was vaccinated, then most likely the skin lesion is not Marek's but...this would also depend on the vaccine that was used and how it was administered - vaccines may not always "take".

Mycoplasma is easily spread among birds. Whole flocks can be carriers and never show any signs of illness/symptoms, then suddenly there can be some type of stress or a bird can become weakened from some other issue and symptoms will arise. Mycoplasma is transmitted both horizontally and vertically - meaning that it can transmit from bird to bird (dust, dander, mucous, etc.) and transovarian (through the egg into the embryo). It's possible that your sick bird may have actually been born with MS and is now presenting symptoms. But without testing, you just won't ever know.

http://ucanr.edu/sites/poultry/files/201395.pdf