With Christmas around the corner, a see-through goldfish might make a nice Christmas present for the ichthyologist who has everything.
The goldfish, with transparent scales that reveal its organs, was developed by a joint research team of Mie University and Nagoya University in Japan.
The fact that it grows to weigh as much as 1 kilogram will make it useful for research into blood constituents and organ behavior. A report announcing the development of the fish was made at the annual meeting of the Molecular Biology Society of Japan in Yokohama on Wednesday.
The research team bred the transparent fish by repeatedly crossing selected pale goldfish over three years.
As goldfish lay several thousand eggs at a time, they will make useful experimental subjects for the observation of blood makeup and the operation of internal organs without scientists having to dissect them.
In research carried out up to now, transparent zebrafish, which also lay a large number of eggs, have often been used, but they are ill-suited for research into studying blood and organs as they are small, weighing about 3 grams.
Mie University Associate Professor Yutaka Tamaru said the newly created goldfish are promising experimental animals that combine the merits of zebrafish and mice because they are easy to breed. "Pale-colored goldfish have little commercial value, but their negative value has turned into a positive," he said.
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