News Letter Vol.4
Kinki University 21st Century COE Program English Site > News Letter Vol.4
'World's first full culture of bluefin tuna' mentioned in Prime Minister Koizumi's policy speech

Osamu Murata (Seedling Production and Culture Group, Fisheries Laboratory)

A letter from Chihiro Tonabe, Deputy Councillor, Cabinet Affairs Office to Hidemi Kumai, COE Leader says 'at the beginning of the Diet session started on the 21st day, Prime Minister Koizumi delivered a policy speech, in which he mentioned Mr. Kumai, though on an anonymous basis, as an example of a university-launched venture business. Your achievements are introduced in magazines and a case book prepared by the Ministry of Economy, Trade and Industry, and Prime Minister Koizumi himself talked about the full culture of bluefin tuna, so we mentioned your achievements in the Prime Minister's policy speech'. Enclosed with the letter was a manuscript entitled 'Promotion of science and technology and response to global environment issues', an item among the many addressed in the policy speech. The manuscript says 'the number of university-launched venture businesses has already exceeded 900, including the world's first full culture of bluefin tuna. We will further strengthen cooperation between the industry and the academic society'. It is a great honor to us that our achievements were mentioned in the policy speech to the 162nd Diet (January 21, 2005). It also provides motivation to further promote the COE Program 'Center for Aquaculture Science and Technology for Bluefin Tuna and Other Cultivated Fish', and we should work even harder.

21st Century COE Program 'Center for Aquaculture Science and Technology for Bluefin Tuna and Other Cultivated Fish'
A detailed introduction to and the current status of the research activities of the Food Safety, Processing, and Animal Feed Group


Yasuyuki Tsukamasa (Food Safety, Processing, and Animal Feed Group, Graduate School of Agriculture)

Electron microscope photograph of the flesh of fully cultured tuna
The Food Safety, Processing, and Animal Feed Group consists of 13 members, including four teachers, two at the Uragami test site of Fisheries Laboratory and two at Graduate School of Agriculture, three COE doctoral researchers, three graduate school doctorate course students, and three graduate school masters course students. A unique feature of our Group is that the percentage of foreign students is high: two of the COE doctoral researchers are from Korea and Bangladesh, and one of the graduate school doctorate course students is from Malaysia.

Our Group's research themes can be classified into three, as the group name suggests.

(1) Development of feed for cultured fish:
General cultured larval fish, such as red sea bream, grow only on the rotifer and brine shrimp larva and is later given formula feed. However, bluefin tuna needs, at the larval stage, cultured larvae and eggs of parrot fish and other fish species in addition to them, and after the larval stage, needs living feed such as sand lance, horse mackerel, and mackerel. However, his feeding process requires lots of labor, so it is imperative to reduce the feed cost, enhance workability and productivity, and develop formula and other feed to prevent environmental contamination. We are developing the feed by investigating the nutritional value of intake stimulants and feed for bluefin tuna, and have already filed a patent application related to the formula feed. We also commit our energy to research on feeding methods that will enhance the growth rate of red sea bream as well as bluefin tuna.

(2) Enhancement of the safety of cultured bluefin tuna:
It is known that mercury accumulates in tuna in large quantities. The assumed mechanism is that tuna is at a high level in the food chain and accumulates a high concentration of mercury through bioconcentration. The type of feed can be controlled at will for cultured fish, unlike natural fish, so it is assumed that the selection of feed with a lower mercury accumulation would make it possible to produce bluefin tuna with a low mercury content. The researches conducted so far show that mercury concentration in the muscles of natural bluefin tuna is around 1.0μ g/g and individual variability can reach dozens of times, whereas the concentration is as low as approximately 0.6μ g/g for cultured bluefin tuna and individual variability is less than two-fold. This indicates the possibility of the concentration being lowered by feed. Thus, we are developing technology for producing bluefin tuna which has a very low mercury content and is highly safe, investigating mercury content in feed fish and the accumulation of mercury by growth. We are also investigating dioxin concentration.

(3) Improvement of flesh quality of cultured bluefin tuna:
Fully cultured bluefin tuna finally grew to a shipment size last year and no research has been conducted yet on the flesh quality of fully cultured bluefin tuna. It is known that the quality of fish changes very quickly after death, but since tuna is refrigerated overnight after caught, we have no knowledge of the changes in quality that may occur immediately after catch. Thus, we are investigating how the flesh quality of tuna grown in the same preserve will change as the seasons change. It is known that fat accumulates in cultured bluefin tuna in large quantities, and it has been conformed that glycogen also exists more in the muscles of cultured bluefin tuna than in the muscles of natural ones. A refrigeration test showed that flesh softens more slowly for bluefin tuna than for other cultured fish species and, among the quality factors of tuna, flesh color is the one which changes most quickly. We are now examining technology for maintaining flesh color while securing safety.

Kinki University's COE tuition exemption and reduction program and COE scholarship

Hiromi Ohta (COE Special Director, Graduate School of Agriculture)

Kinki University offers a tuition exemption and reduction program and a scholarship so that Graduate School of Agriculture doctorate and masters course students at COE can devote themselves to advanced research without having to worry about money. I would like to give an outline of these programs below.

First of all, Kinki University has a program for granting a 50% tuition reduction to 25 masters course students and allowing an exemption for ten doctorate course students. On the basis of the research plans and TOEIC certificates submitted by applicants and recommendations by their tutors, the COE Promotion Committee reviews and screens the applicants, and the President makes the decision at the recommendation of the Graduate School Director. An especially important selection criterion is the TOEIC score because young researchers should have a good command of English in order to make their researches known to the world and it is necessary to ensure that entrants from other universities or specialties are screened by fair criteria.

In addition to this tuition reduction and exemption program, a scholarship of 100,000 yen a month is granted to five doctorate course students so that personnel who will lead world-class researches will be developed at this education site. At the request of applicants, the Promotion Committee reviews and screens the applicants on the basis of the recommendation of their tutors, examining their researches and plans, achievements, and motivation. Scholarship students are determined by the President at the recommendation of the Graduate School Director.

I sincerely hope that the students will use these programs, develop themselves at the COE, and go global with confidence.