By Susan Milius
Biologists have implanted male-reproductive tissue from rainbow trout into male and female salmon, which then bred a new generation of baby trout.
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In male-salmon recipients, the trout tissue produced sperm, but in female salmon, the same tissue produced eggs, says Goro Yoshizaki of the Tokyo University of Marine Science and Technology. These surrogate parents produced trout that grew up to breed in the usual way, Yoshizaki and his colleagues report in the Sept. 14 Science.