Rainbow trout prosper on energy-rich feed
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Ioannis Zabetakis The Salmon of Knowledge
nce upon a time (in one of my beloved Celtic stories), Fionn mac Cumhaill, the great leader of the Fianna of Ireland, was still a young boy and he was sent to live with a very wise man named Finnegas.
Finnegas was a poet who lived on the banks of the river Boyne and was renowned throughout Ireland for his vast knowledge. As well as being renowned for his skills in composing and reciting poetry, Finnegas knew more about the ways of the world, including the secrets of the birds and animals and plants and stars, than any other man in Ireland. It was because of his vast knowledge that Fionn had been sent to learn from Finnegas. Fionn loved to listen to the old man’s wonderful stories and his many words of wisdom which he too, in time, would learn to recite. In exchange for the wisdom Finnegas would pass on to him Fionn would help with house chores like cooking and cleaning, but also fishing for the old man. However, despite Finnegas’ vast knowledge, he did not know everything and there were times when Fionn’s endless curiosity got the better of him, and he was left unable to answer the young boy’s questions. ‘Is there a way to know everything?’ Fionn asked him. This was a question that Finnegas had asked once too and was the very reason why he now lived next to the river Boyne. It had been told by the druids of old that living in a still, dark pool in the shade of the overhanging hazel trees was the Salmon of Knowledge. It was as result of eating the nuts of these magical hazel trees that the salmon had acquired all the knowledge of the world. And so it was, that, according to prophecy, the one who would eat the salmon would gain the knowledge for themselves. Finnegas had been living on the edge of the river for several years now, attempting to catch the salmon and gain such wisdom. And the story goes on…and we still do not know if Finnegas e: ioannis.zabetakis@ul.ie
has been successful in his pursuit of the Salmon of Knowledge. This story came to my mind when I read the news from the other side of the Atlantic: “Fisheries and Oceans Canada is in Federal Court this week defending a policy that allows salmon farming companies to transfer juvenile salmon from land-based hatcheries into ocean pens without first testing for piscine reovirus or PRV”. Biologist Alexandra Morton, represented by Ecojustice, and the Namgis First Nation have challenged the federal policy in separate cases that will be heard together. They argue that PVR is a “disease agent” and therefore it should be illegal for salmon carrying the virus to be transferred into the ocean. The Namgis case also argues that the federal government failed to fulfil its duties to consult and accommodate when issued licenses for salmon farms to transfer juvenile salmon into the ocean without testing for the virus. “We are simply arguing that the Minister of Fisheries needs to screen for this virus,” said Morton ahead of the first day of hearings, few weeks ago. “Screening is the very least he can do, right now what he’s essentially done is cloak himself in wilful blindness to whether PRV is being delivered to our oceans through these fish farm hatcheries,” added Kegan Pepper-Smith, one of the Ecojustice lawyers representing Morton. In Norway and other regions around the world, PVR has been shown to cause heart and skeletal muscle inflammation in Atlantic salmon — a disease that can be fatal in some cases. It is a major concern for environmental groups and First Nations worried about the impact of fish farms on wild salmon. In conclusion, some authorities around the World need to have a bit more knowledge of the interdisciplinary issues between farmed and wild fishes. I may have to send them a copy of the story “The Salmon of Knowledge”…
@yanzabet
Currently working on Food Lipids at the University of Limerick, Ireland, focusing on feeds, food and nutraceuticals against inflammation, Ioannis is a co-inventor in two patents, has edited a book on marine oils, and has published more than 60 peer-reviewed articles (h-index 19). He is currently writing a book on "The Impact of Nutrition and Statins on Cardiovascular Diseases" for Elsevier. 6 | October 2018 - International Aquafeed
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rials on rainbow trout at Aller Aqua show significantly higher growth, lower FCR and improved nutrient retention in fry of rainbow trout when fed a more energy-rich feed. In relation to this new discovery, Aller Aqua have relaunched a higher fat and energy content version of their Aller Futura Ex, now fully dedicated to the nutritional requirements of rainbow trout and other salmonids. With a balanced protein to fat ratio, it is more suited to larvae and fry of marine species as well as species with lesser energy requirements. For the most delicate early stages Aller Aqua will this month launch its new premium starter diet for fish larvae and early fry, Aller Infa Ex Gr, assembling only premium ingredients, including high levels of krill meal, and the highest standards in production technology. With particle sizes as small as 0.1 mm, Aller Infa Ex Gr is perfectly designed for the delicate stages of fish larvae and early fry, to support healthy development, fast growth and high survival rates. By the time they start feeding, the larvae of many fish species are not fully developed. Some lack a fully developed stomach with the complete range in digestive enzymes, and the digestion of feed particles as well as the nutrient uptake is of highest importance to match the high potential for growth. To aid the developing fish in their digestive processes and organ development, Aller Futura Ex Gr, Aller Infa Ex Gr and Aller Thalassa Ex Gr are naturally enhanced to support organ development and health of the liver and the gallbladder, said Robert Tillner, product manager of Aller Aqua.