Date of this Version



© 1993, The Board of Regents of the University of Nebraska on behalf of the University of Nebraska–Lincoln Extension. All rights reserved.


This NebGuide will aid in the early identification and proper management of bovine ocular neoplasia, commonly known as cancer eye, including appropriate veterniary care. The common name for bovine ocular neoplasia, also known as ocular squamous cell tumors, is cancer eye. The term cancer eye is not entirely accurate and carries negative connotations. As we will explain in this NebGuide not all of these growths are cancerous. The scientific term for a cow is "bovine," the medical term for the eye is "ocular," and the medical term for these new and abnormal growths is "neoplasia." Thus, the term bovine ocular neoplasia or BON is more accurate and less objectionable. Bovine ocular neoplasia (BON) includes a variety of benign and malignant skin tumors of the eyeball and eyelids. Benign tumors are growths that do not spread to other parts of the body and do not tend to grow into surrounding tissues. They can cause local problems with eye function, but do not affect the rest of the body. Malignant tumors are growths of cells that spread to other parts of the body and tend to invade surrounding tissues. Because cancerous tissue (tumor) is not acceptable for human consumption, any affected part of the animal's body will be condemned and an animal with evidence of a tumor that has spread to another part of the body is totally condemned.