Ten transgenic piglets born this year in a laboratory in China look like ordinary piglets but under a black light, they glow a greenish tint.

The animals achieved the ability to glow owing to a genetic alteration that incorporates a protein transferred from jellyfish DNA.

The glowing piglets are the latest in a series of animals-turned-florescent with an active transgenesis technique developed at the University of Hawai'i at Ma-noa, a journal reported.

Earlier this year, the technique was also used to produce the world's first 'glowing green rabbits' in Turkey.

When applied to the piglets, the success rate which the fluorescent proteins from jellyfish DNA were transferred into the embryo of the pig was quadrupled, the university said.

The green colour simply indicates that the fluorescent genetic material injected into the pig embryos has been incorporated into the animal's natural make-up.

"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," said Dr Stefan Moisyadi, a veteran bio-scientist in the UH medical school's Institute  for Biogenesis Research (IBR).

Moisyadi said the animals are not affected by the fluorescent protein and will have the same life span as other pigs.

"The green is only a marker to show that it's working easily," he added.

The ultimate goal is to introduce beneficial genes into larger animals to create less costly and more efficient medicines.

"For patients who suffer from hemophilia and they 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," Moisyadi said.

Dr Zhenfang Wu and Dr Zicong Li of the South China Agricultural University have detailed the research that produced the transgenic pigs in an article submitted to the Biology of Reproduction journal.