The only specialised marine publication in Oceania that focuses on the maritime industry, from super yachts to small craft to large commercial ships, including coastal shipping, tugs, tow boats, barges, ferries, tourist, sport-fishing craft
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ACROSS THE DITCH The LONGEST Lever BY JOHN MOSIG ABOVE: One Cictorian abalone grower is producing market size stock in 30 months after 10 years of a selective breeding program. Before that the industry norm was 42-48 months before they���d cleared out a run of spawning stocking BELOW: The new improved barramundi ��� the heavy shoulder & thicker, deeper body is what the industry is aiming at f given a long enough lever, Archimedes could move the world, have we got one for aquaculture? Sure have. In fact we���ve got two: genetics and nutrition. Over this side of The Ditch we���ve got a couple of feed mills that do their best to provide us with species-speci���c diets and I���ve seen both their labels on bags across on your side so we can presume they���ve got their diet formulae: yes I can speak Latin, pretty much in the ball park, at least for the species for which the nutrient pro���les have been developed and are found in suf���cient numbers for a worthwhile feed I 12 ��� NZ AQUACULTURE ��� JANUARY/FEBRUARY 2013 run. But what about genetics? As a sign of the growing sophistication of the industry over in the Land Girt By Sea, more and more operations are biting the bullet and taking the costly, courageous and visionary step of embarking on a genetics program. Not a lot yet mind you, but for every one doing it there���s another four or ���ve waiting to see how it all works out. Is it costly? Holding back the better growers to use as breeders is one thing. We���ve been doing that with sheep and cattle for a few thousand years but with modern genetics we can do far more, and yes, it comes with a price tag. And let���s give credit where credit���s due. It could be said that Gregor Johann Mendel is to genetics what Darwin is to evolution. Born in 1822 on the family farm in German speaking Selesia, now part of the Czech Republic, he studied physics and philosophy to became an Augustine priest and a scientist. Now those were the days, eh? His experiments with plants revealed to him the mysteries of inheritance and the pre-determined patterns it followed. He was a bit before his time and the monumental impact of his breakthrough observations weren���t recognized until the 20th Century. Now they govern how we live. Big statement? Take the genetics factor out of the food we grow and see how many of the Planet���s eight billion and counting, are left in 12 months time. And how the global economy is holding up? Pig and poultry prices will be through the roof and we���ll be back on the barter system. But let���s not dwell on the gloomy side of life. Let���s include Gregor Johann in our daily prayers, his Law of Segregation and Law of Independent Assortment later became Mendel���s Law of Inheritance and the launching pad of modern genetics. Getting back to genetics in aquaculture. We���re going to have to have a huge improvement in just domesticating wild species. This is ever so apparent with some of the species we���ve tried to farm here in Oz.We���ve seen lots of spectacular growth from the shooters, but the growth range from ���sh that have evolved to ���ourish in the inland sea of an ozzie old man ���ood and, when the rains fail, a string of muddy waterholes the next, is all over the shop like a burst bag of wheat when it comes to size variation within the species. Murray cod (Maccullochella peelii peelii) and yellowbelly (Macquaria ambigua), are two wild-catch market favourites that have failed spectacularly when farmed. Despite the millions squandered by ���sheries scientists and administrators on developing them, farmed Murray cod only hold a niche market and yellowbelly are a rarity, even in the Asian wet markets where they have a strong following. But we���ll save that one for another time. We were talking about what a costly, and it follows courageous, step it was. Based on Mendel���s Laws of Inheritance, monitoring the performance of family lines, recording them and holding the family lines is just the beginning of the outlay. The results have to be analysed and future pairings have to be decided on and trialled. Most farms that embark on a genetics program have around a hundred family lines to choose from. Imagine doing that without a computer! Courageous? Well, to start with there���s the cost. It���s considerably more than signi���cant. Let���s say substantial.