In New Orleans

May 14, 2008 20:41 GMT  ·  By

Nowadays, not only iguana and parrot pets get to be green. Dogs too can do it. And, mind you, we?re not talking here about painted dogs from commercials. Recently, a green-coated puppy has been born at a New Orleans animal shelter. The puppy's coat looks as if it should have been white, displaying a decidedly verdant tint.

The other siblings in the litter were colored normally, white or brown. Specialists say its green fur is the result of a natural process, stating that the dog's coat won't stay green forever. It should fade to a more normal dog color of white or tan within two to four weeks.

"Sometimes, when a puppy is born, the amniotic fluid mixes with the placenta and dyes the coat of the puppy and it almost always happens to very light colored puppies. There are not health concerns - it's really just a discoloration in the birthing process," said Anna Zorrilla from Louisiana SPCA.

Other odd green animals are not so natural, being the result of genetic engineering. The protein named aequorin, from the luminescent jellyfish Aequorea victoria and many other marine organisms, produces a blue glow in the presence of Ca2+ ions, due to a chemical reaction; that's why it has been used to picture calcium flow in cells in real time.

American, British, South Korean, Japanese and Chinese teams managed to successfully breed partially-green fluorescent pigs in order to boost stem cell research, using the Green Fluorescent Protein (GFP) gene from this jellyfish. The mouth, trotters and tongue of the pigs are green under ultraviolet light. Fluorescent green pigs even passed the trait on to their young.

In nature, only fireflies and marine creatures (like jellyfish, abyssal squids, fish, and others) are fluorescent, but, after researchers have managed to obtain fluorescent pigs, rabbits, butterflies and tank fish, based on genes from these creatures, now we can have fluorescent cats, too.

The same Green Fluorescent Protein (GFP) was inserted by a South Korean team in the cat genome. Unlike pigs, the genetically engineered cats glow red in the dark when exposed to UV light, because of the red fluorescent protein in their skin, while an ordinary cat will appear green.