Here’s a company in Canada who culture an Algal Paste which can be used for improving the development of early stage larval marine fish being cultivated in tanks;
http://www.innovativeaqua.com/
Greenwater Formula
Green water formula, Nannochloropsis oculata (2µ), is used in the culture of early stage larval marine fish. Our Green water formula is designed to create diffuse light conditions for the first feeding of larval marine fish. Not only does it help to initiate first-feeding, it has acted to promote schooling activity and alleviate the problems associated with “nose-banging”. Its’ great fatty acid profile also means quality food available to rotifers in the tank. Cell densities are approximately 30 billion cells per ml. of paste.
This Algae’s positive uses are supported in the following report -
Green water: Optical rather than nutritional effect. pp. 266-269.
Marliave, J.B. 1994.
1994 AZA Conference Proceedings, Atlanta, GA
Where the author finds, “the halibut larvae in clear water concentrated at the water surface and near the tank walls, whereas in green water the larvae spent most of the time in the water column, searching for prey.”
and, “In clear water, larval hexagrammids tended to swim cross-current into tank walls, and showed poor survival rates. The use of algae paste to reduce visibility resulted in slower swimming, active feeding and formation of schools, with higher survival rates”
Given the need to find alternative sources of food and better methods of cultivation I found this innovation quite interesting.
Sean
Marine Biologists in Taiwan have isolated a gene that moderates cell death in algae, and could allow them to provide early warning in the aquaculture industry.
A team led by Chang Jeng of National Taiwan Ocean University has developed a molecular probe that is able to predict the cell death process among algae. Using the probe, the aquaculture and fishing industry will be able to know in advance about any mass die-off in algae, an important food source for fish in the natural environment.
If such large-scale losses of algae can be predicted, facilities such as open-ocean fish farms can take remedial action (e.g, increase levels of feed supplied to caged fish) to mitigate loss of smaller feed fish affected by the loss of algae.
Early detection of algal loss could also help predict other changes to the farmed fish environment and take appropriate action.
A series of patent documents outline a field of invention that may be part of the solution to the aquaculture feed protein and oil deficit. This deficit, derived from short supply of wild caught fish has the potential to undermine the growth of aquaculture.
Finfish discussed the problems with the global supply of fish meal here.
Microalgae (single celled algae or phytoplankton) represent the largest, but most poorly understood, kingdom of microorganisms on the earth. As plants are to terrestrial animals, microalgae represent the natural nutritional base and primary source of all the phytonutrients in the aquatic food chain.
As the primary producers in the aquatic food chain, microalgae are the source of many phytonutrients, including docosahexaenoic acid (DHA) and arachidonic acid (ARA) precursors for the valuable nutritional component widely promoted as Omega 3 Fatty Acids.
Microalgae also represent a vast genetic resource, comprising in excess of 80,000 different species.
Yeast, filamentous fungi, and bacteria are also in the direct food chain of fish, crustaceans, and mollusks. However, only a very few of these microbes, perhaps less than 10 species, have been exploited for aquaculture feeds.
These few species have been used primarily for historical reasons and ease of cultivation. They have not been chosen on the basis of any scientific evidence of superiority as nutritional or therapeutic supplements.
The marine environment is filled with bacteria and viruses that can attack fish and shellfish, thereby devastating aquaculture farms very quickly. Bacteria and viruses can also attack single celled microalgae, so these organisms have evolved biochemical mechanisms to defend themselves from such attacks. Such mechanisms may involve the secretion of probiotic compounds that inhibit bacterial growth or viral attachment.
Can you point to any additional material on algae as an aquaculture food source?
What do we know about optimising the economics of production?
What wholesale cost would the feed need to be produced at in order for the major feed companies to adopt this technology as a food component for aquaculture and other intensive forms of animal production?
The patent documents which describe this endeavour can be found here.
Advance Bionutrition Corp (the assignee of the patent is hot on the trail of non fish meal derived aquaculture feed.
