Japanese King Prawns, which grow up to 25 per cent faster or larger than wild-caught prawns, have been developed by CSIRO fisheries scientists and a local prawn farmer.
The advance has given Australia a chance to lead the world in the selective breeding of crustaceans for our burgeoning $400m a year aquaculture industry, CSIRO program leader Dr Peter Rothlisberg says.
The outsize Japanese King Prawns (also known as Kuruma prawns) are the result of a sequence of breakthroughs in breeding achieved by a team from CSIRO Fisheries in Cleveland, Brisbane, led by Dr Nigel Preston.
Their first advance was to successfully "close" the life cycle of tiger prawns, so they could be bred and reared to maturity on farms. The second was to demonstrate that prawns with faster growth rates and larger sizes could be selected for breeding to produce an improved stock.
The result, already tested in farm trials, is a prawn which matures three weeks earlier, or else grows up to 25 per cent larger than a conventionally-bred farmed prawn.
Dr Preston said the gains had been achieved using prawns selected from wild stock, as a result of a classic heritability trial. "Mendel would have been delighted," he observes.
A further achievement was to prove the potential use of "microsatellites" or natural indicators concealed in the prawns' DNA to help breeders improve selection for traits such as size, colour, disease resistance, suitability to various environments and so on.
Working with molecular biologists from CSIRO Division of Tropical Agriculture, who have used similar techniques to improve cattle stocks, the team were able to further enhance the prawns' growth rate by identifying the genetic markers which pointed to high growth potential of particular individuals.
"These prawns have a very high value on the Japanese market," Dr Preston says. "Prawns shipped from Australia and sold live in Japan can fetch up to $A170 a kilo. The high price is partly because they are so aesthetically pleasing."
Dr Rothlisberg said the faster growing prawn had important ecological consequences, enabling Australia to raise production without increasing the impact of prawn farming on the environment. It also offered greater flexibility and market options to farmers.
More information: Dr Nigel Preston, contact no. for Dec 23 mobile 018 072 577. Dr Peter Rothlisberg (07) 3826 7257.
Available pictures: Dr Preston with "Sumo" prawns -- one third larger than normal sized prawns.
Vision/picture opportunity: CSIRO lab assistant with large prawn. CSIRO Lab media contact: Katherine Johnson mobile 07 3826 7290 or 0419 704 084.