A university in Japan recently became the first to successfully breed Japanese eels by hatching fish larvae from older ones farmed in the facility, amid a rapid decline in the fish species' numbers in the wild and a heightened interest in conservation efforts.
Kindai University in Osaka Prefecture, western Japan, recently achieved a "full-cycle" aquaculture of the eels, an endangered species and a prized delicacy. But although hopes are high about utilizing the method for commercial use, the goal has yet to be realized.
The university used similar methods to those of the state-run Japan Fisheries Research and Education Agency, which in 2010 became the first facility in the world to achieve full-cycle eel farming, a process that involves incubating and cultivating eels so they produce offspring.
Although eels available on the Japanese market are 99.9 percent sourced from farms, they usually first need to be caught in the wild while still young, and a massive decline in catches has generated greater interest in the technology as it would enable producers to breed the fish from their eggs.
The university removed the eggs from a female eel for artificial insemination and then allowed the hatchlings to reach maturity before repeating the process to establish a full breeding cycle.
But the university said it has struggled to sustain a large population of young eels due to the many mysteries surrounding their biology.
The juvenile eels, known as glass eels, take time to mature and maintaining them can be complicated as their eating habits often make their tanks dirty, according to the university.
"We will focus on developing the technology to raise glass eels and help in their mass production," said Shukei Masuma, a specially appointed professor at the Aquaculture Research Institute at the university.
The university has also achieved full-cycle farming of bluefin tuna.
