Can you tell if she may have a small injury/peck or sting to the comb?
Any lice or mites?
Is she not well - are you having to keep her inside?
Any symptoms like lethargy, not able to move about well...etc.?
there doesnt appear to be any obvious focal point of the swelling, no obvious scabs or anything oozing. I haven't seen anything crawling around in her feathers, although I have never an opportunity to identify lice or mites on any of my chickens previously, so I'm not exactly sure that I would know one from the other; never-the-less, no tiny specs moving about, that I can see.
Cricket and her sister sleep inside the house at night, but they come and go, milling about in the garden and mingling with the rest of the flock during the day. Her appetite seems normal, and she's as active as she usually is but I have been picking up a kind of nervous, restless energy from her...almost frantic, at times, but not for any determinable purpose, that I can figure. She and her sister share a nest for egg laying in my bedroom & I've found her on it every few days, which is pretty normal for her. I don't think she's getting broody, tho she can be; she hatched two broods this year, and are old enough to be independent now. I guess it could be hormonal but her comb has never been effected before.
She hasn't developed any neurological ticks or exhibited any confusion but the last time they went for a ride with me to run errands, she jumped out, while I was exiting the car....she is a seasoned co-pilot and has never attempted jump out of the car before. At the second stop, I was now alert to her interest (having just collected her, with some effort, from an almost empty parking lot), yet she was so determined that even with my effort to keep her from doing so, she leapt to explore a much more active and populated parking lot. And like any nightmare scenario, she refused to come to me, opting rather to zoom under parked cars, playing " catch me if you can"! As I circled the car that had been idling in front of the store, mortified and spilling with apology for the spectacle, a good Samaritan, with "chicken experience", came to our rescue and helped me corner her at a bush. SO- this is NOT normal behavior for Cricket, AT ALL. I suppose it could be her midlife crisis but something tells me that she is bothered or uncomfortable and maybe going a little coo-coo, as time passes. Which is what has led me to wonder if she has a mass or growth maybe starting in jher sinus area? She doen't seem to be rubbing her head or acting like its irritated...only time will tell if her comb will continue to become more swollen- if that will even be something I can measure some how? I'm just hoping that someone has already gone thru a similar experience and can shed some light or point me in the right direction, so I can figure out where to take her for help... there are Avian vets in Pullman, thru WSU and there are also Avian vets in the seattle area, but their facilities are all different, as far as diagnostic and treatment options.