Taiwanese scientists have successfully bred three fluorescent green pigs.

A team at the National Taiwan University injected fluorescent green protein into embryonic pigs, which resulted in three male transgenic pigs, says professor Wu Shinn-Chih of the university's Institute and Department of Animal Science and Technology.

The scientists hope that monitoring changes in the tissues during physical development will help boost stem-cell research.

"There are partially fluorescent green pigs elsewhere, but ours are the only ones in the world that are green from inside out. Even their hearts and internal organs are green," Wu says on Thursday.

A company in Taiwan created the first genetically engineered fish in 2003. Environmentalists protested the creation saying the transgenic fish threatened the earth's ecosystem, according to Reuters.