Farming bluefin tuna

This is an interesting article on the attempts to produce viable tuna fingerlings to stock Japan's existing bluefin tuna "farms", which I assume are really just fattening pens for wild-caught fish.  Apparently the inability to produce spawn is the major sticking point in Japanese tuna farming right now, such that the large-scale production of spawn would totally revolutionize the sector.  If my understanding is correct, there is no true tuna farming in Japan, but rather a sort of tuna taming.  The difference between tame animals and domesticated animals is that tame animals are born wild and then captured and raised, like Asian elephants trained to work for people.  Domesticated animals, on the other hand, have their life cycle totally controlled by humans, like a cow or a pig.  If the research profiled in this NYT article pans out, it would mean the transition of Japanese tuna farming from a primitive wild capture and fattening system to true domestication.