I have an old hen about 8 years old who is showing odd behaviour. She stretches her neck and opens her mouth and squawkes. She has been doing it for weeks now. If she was a mammal I would say she had something in her throat. She is eating and is a good weight with no obvious signs of illness. She doesn’t move around as much as my other hens..free range..but she is older. I have had hens for 30 years or so but never seen this. Any advice welcome.