This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
Keywords from Image Description:
FMIB Brook trout showing massive thyroid tumor in the mouth cavity springing from the floor of the mouth.jpeg Brook trout showing massive thyroid tumor in the mouth cavity springing from the floor of the mouth Subject Brook troutDiseases Tag Fish Cite book Carcinoma of the Thyroid in the Salmonid Fishes Bulletin of the United States