My 1.5 year old serama hen is producing really thick saliva and a bit more of it than she should be. When I first looked at her I thought she had just eaten a slug and it got stuck. I then tried to pull it out and fount it was stuck to her tongue and wouldn't come off. I then soaked and loosened it and thought her tongue had melted or was swollen from an allergic reaction. I pulled all of the slime off and her tongue is normally sized, but a little bit swollen and a bit darker pink than normal, though not red. When she eats her food gets stuck to her tongue and the rest her mouth and starts to build up in a gross slime. What causes this and what can I do? My concern is her trouble eating. She is doing fine with wet food that is a bit slicker and scrambled eggs.