JUL | AUG 2016 - International Aquafeed magazine

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by Diogo Thomaz, Stella Adamidou, Dr Florian Nagel & Dr Hanno Slawski – Aller Aqua Group A brief history of sea bream nutrition

ea bream and Sea bass farming started in the early eighties in the Mediterranean, at a time where knowledge about the nutritional requirements of these species was practically inexistent. At that time only cold-pelleted feeds were manufactured with a small number of ingredients such as wheat, fishmeal, fish oil, soya and a variety of plant oils and meat meals. Protein origin was mainly from fish and animals, and inclusion levels in the diets were very high, exceeding 50 percent. Fat content was very low, below 12 percent, and the main issue was to form a pellet, which could be consumed by the fish. As years passed, technologies evolved and from cold pelleted feeds we went one step further to steam-pelleted diets; in the mid 90s extruded feeds started to be produced extensively, turning the page in the history of fish feeds.

physical characteristics of feeds and improved digestibility of ingredients. Meanwhile academic and company researchers were working on the nutritional requirements of the species and the industry was continuously trying new formulas. Extruders were the tools for the evolution of feeds. From gross protein, amino acids and fat levels, we moved to digestible protein/digestible energy requirements and from fixed diets to flexible diets. Fishmeal and fish oil substitution

The introduction of extruders

Extruders increased flexibility on the number, the type and the quantities of raw materials formulators could use. At the same time the new technology offered a number of options on the 38 | July | August 2016 - International Aquafeed

Dr Florian Nagel at the Aller Aqua Research facilities