The Kinki University Fisheries Research Institute succeeded in artificially hatching Japanese eels, and the fry breeding period has reached 50 days.In the future, the first goal is to grow up to the juvenile Japanese eel "Shirasu eel" with a total length of about 5 to 6 cm, and further research will be continued with the aim of complete aquaculture.
Eel is an indispensable ingredient in Japanese food culture, but more than 99% of domestic consumption depends on aquaculture.Natural fry called glass eels are used for all seedlings that are the source of eel farming, but in recent years, the amount of glass eels caught has decreased significantly, and securing seedlings necessary for eel farming has become an issue.
Research aimed at complete aquaculture of eels has been carried out for a long time, and artificial hatching was successful at Hokkaido University in 1973, and complete aquaculture was successful at the Fisheries Research Agency in 2010, but mass production at a practical cost is not possible. It has not been put into practical use even now.
Kinki University Fisheries Research Institute started eel seedling production research at Shirahama Experiment Station in 1976, and although it succeeded in egg collection and hatching in 1984 and 1998, it did not reach the point of eating food, and after that, research It was interrupted.However, in March 2019, at the Uragami Experimental Station in Wakayama Prefecture, research was resumed with the aim of producing artificial eel seedlings based on the technical information developed by the Fisheries Research and Education Agency and already published.In addition to improving the facilities, we will artificially promote maturation from June using farmed eels as larvae candidates for males and females, and on September 3, we will collect a total of about 6 eggs from three females and artificially inseminate them. About 9 larvae were born.Furthermore, on September 11, about 3 eggs were obtained from one female, and on October 60, a total of about 4 eggs were obtained from two females, and tens of thousands of larvae hatched each.Some of the hatched larvae started feeding from the 9th day after hatching, and currently, about 18 1-day-old larvae (total length about 40 mm), about 10 3-day-old (about 2 mm), and 70-day-old (about 7 mm). ) About 50 fish are growing steadily.
In the future, Kinki University will set up a project team and aim to put all of its strength into practical use in eel farming.To that end, we will first work on the development of new feeds for eel larvae by taking advantage of the characteristics of the Uragami Experimental Station, which specializes in feed research, and focus on raising glass eels that can be used as seedlings for aquaculture.
