I'm sorry to hear about your Olive Egger. The symptoms you're describing—constant mouth opening and closing, inactivity, hunched posture, droopy wings, ruffled feathers, and lack of droppings—can indicate several potential issues. Here are a few possibilities to consider:
- Respiratory Issues: Chickens can develop respiratory infections that may cause them to exhibit unusual behaviors, including mouth breathing or opening and closing their beaks.
- Crop Problems: While you mentioned she doesn't have food in her crop, it's possible she could have a crop disorder like sour crop or impacted crop, which can cause discomfort and lead to unusual mouth movements.
- Dehydration: If she's not drinking enough, it could lead to lethargy and inactivity. Make sure she has access to fresh water at all times.
- Parasites: Internal or external parasites can affect a chicken's health significantly. Consider checking for signs of mites, lice, or worms.
- Stress or Illness: Stress from changes in the environment or illness can also lead to reduced activity and appetite.
- Coccidiosis: This is a common disease in young chickens that can cause lethargy and poor appetite. Look for signs like blood in the stool (though you mentioned no poop at all).
Given her symptoms and the fact that she's not pooping, it may be best to consult a veterinarian who specializes in poultry. They can provide a proper diagnosis and treatment plan. In the meantime, ensure she is kept warm, hydrated, and comfortable.