UQ researchers tackle fishy Japanese problem
Two University of Queensland researchers are helping Japanese aquaculture farmers improve management and husbandry of a popular Japanese eating fish.
Dr Ian Whittington and Dr Ingo Ernst, of UQ's School of Molecular and Microbial Sciences are studying the basic biology of a common parasite of farmed Japanese table fish to reduce fish mortality.
Dr Whittington said the project was important financially and culturally, as seafood formed such a large part of the Japanese diet.
"An average Japanese person consumes 80kg of fish a year, with the largest aquaculture species being the Japanese yellowtail, a fish with good eating qualities popular for sushi and sashimi," he said.
"However, this fish has about a 20 percent mortality rate from various diseases such as parasites, which do not affect humans but can prove fatal to the fish.
"As about 160,000 tonnes of yellowtail a year find their way on to the Japanese market at a wholesale value of $US1.5 billion, any techniques to improve management could be very important financially to the Japanese fin-fish aquaculture industry."
Dr Whittington is an expert on monogeneans, tiny parastic flatworms which live on the gills, fins and skin of fishes. His research interests include the basic biology of monogeneans, and also developing powerful marine glues from the parasites.
Commercial partner Nutreco Aquaculture Japan conducted a literature search to identify the foremost international expert on monogeneans, and came up with Dr Whittington's name. Dr Ernst last year completed a PhD on parasites co-supervised by Dr Whittington.
The firm is sponsoring a two-year, $150,000 project by Dr Whittington and Dr Ernst in the southern Japanese islands of Shikoku and Kyushu, where a large aquaculture industry for yellowtail flourishes.
"It's a happy coincidence of interests. The company lacked the knowledge of the biology of the parasite while this project gives us an application for our expertise," Dr Whittington said.
Dr Ernst said the parasites could spread rapidly in farmed populations where large numbers of fish were captive inside floating sea cages in small areas. The current methodology used by farmers to overcome the problem was to treat the fish in fresh water baths. Although the treatment is effective, it is labour-intensive, expensive and stresses the fish.
Dr Ernst has made three trips to Japan during 2000 to meet with farmers and accumulate information on the culture conditions for the fish, algal growth on cages, water temperatures, parasite/host interactions and other factors. He is developing a computer model to more accurately predict the growth of parasite populations under different scenarios.
"A large component of the project is to build relationships with individual fish farmers and relate our results to their experiences so the farmers can see progress on the project and understand more about the biology of the parasites," Dr Ernst said.
"This way farmers can apply the new information immediately with potential benefits."
Nutreco Aquaculture Japan representative managing director Joep Kleine Staarman said the company was impressed with the practical approach Drs Whitington and Ernst were taking to the parasite problems of Japanese fish.
"The way they interact with the Japanese farmers while collecting information and samples suggests there are no cultural differences between Australia and Japan especially when they present their findings to the farmers and give advice on how to manage the farms," Mr Staarman said.
"So far, information has mainly been collected on the parasites' biology but with this better understanding, we are confident of solutions. However, this may take time. We look forward to a continued research collaboration with UQ over coming years and eventually to solve or diminish the parasite problems in warm-water fish."
For further information, contact Dr Ian Whittington (telephone 07 3365 3302 or email: i.whittington@mailbox.uq.edu.au), Dr Ingo Ernst (telephone 07 3365 8549 or email: Ingo.Ernst@mailbox.uq.edu.au), Joep Kleine Staarman (telephone +81 92 432 1301 or mobile +81 90277 43271) or Shirley Glaister at UQ Communications (telephone 07 3365 2339).
