A new diet aimed at helping tuna farmers avoid the biosecurity risks and sustainability issues associated with baitfish diets has been launched by Skretting.
The company evaluated several feed types and found that a soft extruded diet was by far the best option for tuna farming. The result, MaGro, is now available in Japan, ideally timed to meet a rising demand for Japanese bluefin in domestic markets and further afield, including Asia and North America.
“Most tuna producers are capital intensive companies and understand the importance of fish sustainability and traceability,” explained Yoshihito Ito, general manager of Skretting Japan.
“As such, many of them have long-term plans to provide overseas markets with sustainably-certified products, if and when such a standard is created. This new diet will help them achieve that aim,” he added.
Clear advantages
Extruded pellet feeds have played a crucial role in the evolution of aquaculture but tuna farming continues to be almost entirely based on baitfish diets. Previous attempts by the industry to replace this feed component have failed with the tuna rejecting the pellets as too hard and unpalatable.
Unlike baitfish which can vary in nutritional profile, MaGro has a consistent formulation and a softer texture than the pellets tailored for other fish farming sectors. Trials have shown that tuna fed with MaGro demonstrated equal or improved growth compared with those fed baitfish and the fish maintain their feeding regime during the colder months of the year.
“MaGro is a sophisticated diet that offers many clear advantages over baitfish. On average, farmers only need to use one-third of the volume to achieve the same or better growth performance,” said Chris van Bussel, global product group manager marine species at Skretting.
