An image of a pig showing striking, blue-tinted fat beneath its skin has racked up more than a million views on Imgur, prompting hundreds of users to speculate about the unusual coloration. The photo was uploaded by a user going by “GlendilTEK,” who captioned it “The Weird Pig.” According to the poster, his in-laws shot the animal on their ranch in Morgan Hill, California. Efforts to reach “GlendilTEK” on Friday were unsuccessful.

In a follow-up note, the uploader clarified that the pig wasn’t opened up until after it had been strapped to an ATV and hauled back to the house, meaning most of the blood had already drained by then. He added that no one in the family has any idea why the fat looked blue. Everything else—the meat and the blood—appeared normal, he said; the only oddity was the bluish fat distributed throughout the carcass.

The poster mused that blue pigmentation can sometimes be linked to copper toxicity, but said the property only contains old, filled-in mercury mine shafts. He also noted that they’ve harvested wild pigs on the ranch before and none showed this kind of color. Contacted Friday, a spokesperson for the UC Davis School of Veterinary Medicine joked the case belongs in the “Freaky Friday” file and emphasized that you can’t draw conclusions from a single photo that might even be staged.

Meanwhile, a spokesperson for the California Department of Fish and Wildlife told the Morgan Hill Times that experts have “occasionally” encountered wild pigs with similar internal discoloration. In those instances, investigators concluded the animals had likely ingested chemicals containing a blue dye. Andrew Hughan, a spokesperson for Fish and Wildlife, explained that pigs will consume pesticides or rodenticides, which can tint the animal’s fat. His advice: don’t eat the meat, and dispose of the carcass properly so the contaminants don’t re-enter the environment.