Animal genetics firm MetaMorphix, Inc (MMI) and Stirius, Inc announced last week their jointly formed AquaAnimal Health, Inc to develop aquaculture technologies to augment output and advance disease resistance in farmed marine animals like finfish and crustaceans. AquaAnimal Health will use MMI’s Myostatin technology to maintain and enhance fish and crustacean quality across all aquaculture breeding.
Natural inhibition of myostatin in finfish was recently shown to produce greater muscle protein (15-20% more) and increase feed efficiency.
Terry Bradley, a professor of fisheries and aquaculture, said that his 10-year research into the inhibition of myostatin, a protein that slows muscle growth, has obtained "stunning results" in the last two years, with trout growing 15 to 20 per cent more muscle mass than standard fish, according to the University of Rhode Island (URI).
"Belgian blue cattle have a natural mutation in myostatin causing a 20 to 25 per cent increase in muscle mass, and mice overexpressing myostatin exhibit a two-fold increase in skeletal muscle mass," said Bradley.
Bradley and his team spent 500 hours injecting 20,000 rainbow trout eggs with DNA types designed to inhibit myostatin. Of the eggs that hatched, 300 carried the gene that led to increased muscle growth. After two years, most fish had the "six-pack ab" effect, even though fish lack standard abdominal muscles. They also have increased musculature throughout.
Some 500,000 metric tonnes of rainbow trout are raised every year in aquaculture facilities across the United States and Europe. In the US, some 1,000 trout farms produce around USD 80 million worth of trout annually.
Assuming Bradley's transgenic fish meet the regulations, it could provide a boost to the industry by enabling farmers to grow larger fish without increasing the amount of feed.
Transgenic fish status report from 2004/2005 (23 pages)
Transgenic fish studies in China from 2005 (10 pages)
Effects of the “all-fish” GH (growth hormone) transgene expression on resistance to Ichthyophthirius multifiliis infections in common carp, Cyprinus carpio L
Genetically modified fish has promoters driving an over-production of "all fish" growth hormone. This resulted in dramatic growth enhancement in several species, including salmonids, carps and tilapias.
1992). "Growth Enhancement in Transgenic Atlantic Salmon by the Use of an "All Fish" Chimeric Growth Hormone Gene Construct". Bio/Technology 10: 176–181. doi:10.1038/nbt0292-176. http://www.nature.com/nbt/journal/v10/n2/abs/nbt0292-176.html.
(15 February 2001). "Growth of domesticated transgenic fish". Nature 409 (6822): 781–782. doi:10.1038/35057314. http://www.nature.com/nature/journal/v409/n6822/full/409781a0.html.
(19 Apr 2005). "Growth and nutritional trials on transgenic Nile tilapia containing an exogenous fish growth hormone gene". Journal of Fish Biology 59 (1): 62–78. doi:10.1111/j.1095-8649.2001.tb02338.x. http://www3.interscience.wiley.com/journal/118974519/abstract?CRETRY=1&SRETRY=0.