Breast Blisters ??

I have a 16 week old cuckoo maran that has a Blister on her Keel well it's to the right at the very bottom of her breast bone we drained it off with a needle it had yellow fluid in it.

The blister is around 2 inich long and 1 inch wide might only be half an inch she eats and drinks just find and seems in no pain with it but she is on a 5 day course of Tylon for her snotty nose.

will this help with the infection in the blister?

unsure of what would cause it these are the things we have in our run.

we use a Emperor Feeder and also a Galvanised Metal Treadle Feeder along with a 25L tripod waterer and you can see what our perches look like in photo any help would be really helpful.

we also have 2 wooden pallets in the run.

any help with what would be the cause would be helpful

Thank you
AL

My chickens sleep on planks similar to yours - but the key difference is the edges of mine are rounded off.  From the photo it looks like yours are quite sharp along the edges which can cause blisters like you are describing, and also aren't good for the girls' feet.

Can you take a plane and run it along the edges of the roosting bars to round them off?

I'll get my hubby on it then Thank you both.