Alrighty, thanks for the info but I am stumped about one thing that Marks just doesn't connect with what went on and is going on, because would Mareks effect new birds (those that have never been exposed) quickly?
I've had many hens from the last episode for years, and if they had Mareks, wouldn't it have spread to others quicker? The hen that just died was a hen that hadn't been around for the last episode (among her two live sisters) and all of them have had no problems despite being cooped up with these hens (which would be carriers since they survived if it was Mareks)for years...
I also have other new chickens in the coop (in cages but still in there) wouldn't they have been infected since its highly contagious?
I also noticed that the only symptoms that lined up were darkened comb and depression; but don't chickens usually get depressed when they are sick? And her darkened comb was because of lack of oxygen I because I think she had fluid in her lungs?
Sorry for the blobbing, but I'm starting to wonder if perhaps she got some sort of respiratory disease instead? Then the gurgling would make sense