A year-old whitetail buck was recently found circling a Tennessee suburb with hair covering both of its eyeballs, according to the National Deer Association. The bizarre condition is a rare example of corneal dermoids, which occur when tissue of a particular type grows in the wrong place on the body.
Residents first noticed the deer circling in Farragut, a suburb of Knoxville, in August 2020, and immediately notified the local wildlife authorities. Because the buck was bleeding, disoriented, and apparently lacked fear of humans, animal control officers suspected that it may have been infected with chronic wasting disease (CWD), and therefore decided to kill the deer in order to prevent the spread of this fatal prion disease.
Sterling Daniels of the Tennessee Wildlife Resources Agency (TWRA) then sent the animal’s head for tests at the Southeastern Cooperative Wildlife Disease Study unit (SCWDS) at the University of Georgia, noting that both of the eyes were covered in hair.
As it turned out, the deer didn’t have CWD but was instead suffering from epizootic hemorrhagic disease (EHD), which can cause fever and disorientation. This would explain the animal’s odd behavior, but not the hairy eyeballs.
In a formal report, SCWDS representatives Dr Nicole Nemeth and Michelle Willis wrote that the deer had disks of skin in place of its cornea, which is the transparent part of the eye that covers the iris and pupil.
“Corneal dermoids, as in the case of this deer, often contain elements of normal skin, including hair follicles, sweat glands, collagen, and fat. The masses generally are benign (noninvasive) and are congenital, likely resulting from an embryonal developmental defect,” they wrote.
–
Speaking to Quality Whitetails, the official magazine of the National Deer Association, Nemeth commented that “we assume these to be congenital (existing at birth), so we surmised that it survived a long time with those.”
“We also assumed the dermoids developed gradually and that the deer was able to adapt to its decreasing field of vision over time.”
This means that the deer probably developed the strange condition in the womb, where its corneal tissue failed to form properly and instead differentiated into skin tissue. Aside from being coated in hairy skin, the buck’s eyes were anatomically normal.
This is only the second-ever sighting of a deer with corneal dermoids, with the first having been killed by a hunter in Louisiana in 2007.