Feline gastrointestinal disease can manifest in a variety of ways. Here are some common symptoms: Vomiting: Cats may vomit due to gastrointestinal disease. Vomitus may be undigested food, foamy material, or contain yellowish bile and yellow fluid. If there is blood in the vomitus, the condition may be serious and you need to seek medical treatment as soon as possible. Diarrhea: Diarrhea is a major symptom of gastrointestinal illness. Cat feces may be liquid and have a fishy and unpleasant odor. In severe cases, the stool may be black or dark-green, and may be accompanied by intestinal mucosal bleeding.

Reduced appetite: Due to damage to the gastrointestinal tract, cats may have reduced appetite, lose interest in their usual favorite foods, and even Refusal to eat.

Abdominal pain: The cat may show symptoms of abdominal contraction, often looking back at the abdomen, and refusing to allow the owner to touch its abdomen. Cats may show discomfort with abdominal pain when handled.