Lay the bird on its back and cut through the side of the mouth, where the upper and lower beak hinge. Examine the mouth for any signs of lesions. Continue to cut through the skin of the neck into the crop. Examine the esophagus, trachea and crop. Remove the trachea or leave it in place, but open it to examine its interior. With the appropriate scissors, make a transverse cut of the beak cutting through the nostrils. This will allow inspection of the nasal cavity and will expose the sinuses.