Why Enrich Rotifers and Artemia Used as Larval First Feeds?
Many, if not most, aquatic animals first feeds are zooplankton consisting of phytoplankton, rotifers, copepods, artemia and other small arthropods.
There is ample evidence that copepods and arthropods use lesser carotenoids found in zooplankton to assemble nature’s most powerful mitochondrial targeted antioxidant di-esterified 3S, 3’S astaxanthin. Larvae dining on zooplankton took in astaxanthin via this pathway. This form of astaxanthin takes up residence in the mitochondria’s plasma membrane and protects its ability to make energy.
There is no evidence that rotifers and artemia possess the chemical toolkit needed to assemble astaxanthin from lessor carotenoids. They are, however, obligate filter feeders with a circa 8 micron mouth gape. Any zooplankton small enough to be taken in are rich in carotenoids including astaxanthin.
It is commercially not viable to replicate zooplankton as a first feed. Hatcheries are forced to make a choice and typically select rotifers or artemia as first live feeds. Rotifers in turn are fed marine algae. This practice effectively removes astaxanthin (and other micronutrients) from predator diets.
While replicating zooplankton is beyond reach, formulating rotifer and artemia feeds that “gut load” these animals with astaxanthin and micronutrients found in zooplankton prior to feeding to predators is economically viable.
Amplifeed(tm) Replete rotifer and artemia feed contains di-esterified 3S, 3’S astaxanthin as well as a variety of other micronutrients. It is used as a finishing feed during the last 24 hours prior to harvesting and an economically viable method of enhancing larval growth rates and health. The feed is milled to 8 microns to match the mouth gap of adult rotifers resulting in nearly 100% uptake into the gut and rotifer cells. We have measured astaxanthin concentrations in rotifer cells at a density of 200 ng/rotifer.
We have tested Amplifeed Replete in over 200 species/varieties of fish including marine ornamentals, shrimp, cod and other pelagic spawners. We observe larval prey fed enriched rotifers and artemia followed by astaxanthin enriched first dry feeds doubled growth rates at 42 days post hatch.
By protecting mitochondrial health using astaxanthin during larval development allows the predator to more efficiently process feeds into the power needed to accelerate growth and develop strong immune system function.