Fibromas aren’t always a big problem, but this one is.
QUESTION: I was wondering if you’d ever seen this or knew what it was. I called the city rangers, and they got the deer, but I haven’t been able to stop thinking about it. I’m in New Brunswick, Canada.
ANSWER: At the risk of sounding somewhat unprofessional, that’s disgusting! While it’s somewhat speculative, I suspect the lump is a fibroma – essentially excessive growth of epithelial and dermal (skin) cells.
Fibromas are typically dark brown or black, except in areas where the hair is white, where they are often tan or pink (un-pigmented). They are caused by a viral infection, although biologists aren’t entirely certain how they are transmitted.
Except in extreme cases where the fibromas interfere with sight, eating, breathing, the ability of the deer to walk or other bodily functions, fibromas are rarely harmful to the deer and should heal over time.
This one appears to have become detached. Given the size of the open wound, it’s quite likely this would result in serious infection – and because it’s so close to the brain, probably death.
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