Yellow on a cat's ears can indicate:
- Allergies: Seasonal or food-related allergic reactions.
- Ear mites: Parasites causing itching and yellow discharge.
- Ear infections: Bacterial or yeast infections with discharge, head shaking, or odor.
- Skin conditions: Bacterial or fungal infections, or seborrheic dermatitis.
If you notice yellow discharge on your cat's ears, consult a veterinarian for diagnosis and treatment.