Pigs may not be able to fly just yet, but at least three of them glow.
Taiwanese researchers said Friday that they bred the pigs with a fluorescent material to help the island's stem cell research effort.
The fluorescent pigs are green from the inside out, including their hearts and internal organs, said Wu Shinn-Chih, assistant professor of animal science at National Taiwan University.
From the outside, the pigs appear to be bathed in a light-green tint, particularly their eyes, mouths and knuckles. Wu said the pigs' embryos were injected with fluorescent green protein taken from jellyfish.
Pigs are commonly used to study human diseases, and Wu contends his technique could help researchers monitor tissue changes. He said fluorescent cells would show up during stem cell treatment of diseased organs, allowing physicians to monitor the healing progress.
"We hope it can help with future stem cell research by cutting down on the time researchers expend," Wu said.
Last year, another team of Taiwanese researchers said they developed an alternative to laboratory mice for testing new medicines -- fluorescent fish.
They took a gene that makes jellyfish fluoresce and transplanted it into the livers of zebra fish, which were later implanted with cancer cells.
The cancerous tissue was highlighted with a special tint, allowing researchers to monitor the effect of drugs.