She could be dehydrated or being kept from food and water, but she also may be showing signs of illness. Before we talk about scary subjects as Mareks disease or others, check her crop, and feel if it is empty, full, hard, or puffy. This is best done early in the morning before she has eaten or drunk water. Feel if she has lost weight in her breast area, or if she is fuller in her lower belly. Does she lay eggs? What does her poop look like? Do her eyes look normal in color with round black pupils? Pictures are welcome. If you can give her some drops of Poultry NutriDrench or Poultry Cell, that would be good. I would be tempted to bring her in to observe her more closely. Reproductive disorders can be common in hens over 2 years, and crop disorders are another common problem.
You might look inside his beak and throat with a flashlight while someone holds his head still. Look for yellow or white patches.
