Chinese scientists have created pigs that glow in the dark, shimmering with a fluorescent green light.
The piglets are seen to shine under 'black' or UVA light after their embryos were injected with jellyfish DNA.
Dr Zhenfang Wu and Dr Zicong Li of the South China Agricultural University have published details of their pig research in the journal Biology of Reproduction.
The green hue shows up the fluorescent genetic material injected into the pig embryos but is not believed to harm the pigs.
"It's just a marker to show that we can take a gene that was not originally present in the animal and now exists in it," Dr Stefan Moisyadi, a bioscientist at the University of Hawaii's Institute for Biogenesis Research told the Daily Mail.
The reason for this bizarre experiment is that the findings could help develop cheaper drugs for humans. The goal of the research is to introduce beneficial genes into larger animals to create less costly and more efficient medicines.
"[For] patients who suffer from haemophilia and need the blood-clotting enzymes in their blood, we can make those enzymes a lot cheaper in animals rather than a factory that will cost millions of dollars to build," Dr Moisyadi explained.
The same method was used to create the world's first glow-in-the-dark rabbits in Turkey earlier this year, where they are currently working to create a glowing sheep.
Glowing animals have been developed in laboratories since the 1980s, and these green fluorescent piglets are the latest examples of the technique. Other experiments done around the world have produced glowing monkeys, puppies and kittens.
In April of this year scientists in Uruguay created a flock of glow-in-the-dark sheep. The flock of nine lambs were born at a farm belonging to the Animal Reproduction Institute of Uruguay, a non-profit organisation. They are expected to announce the results of their research in early 2014.
Watch the squealing glow-in-the-dark piglets