(upon the recommendations of Gusev E.E., Bogatova I.B., Patrick Sargelos, etc.)
I. DRY CYSTS
1.1. When buying dry Artemia cysts, it is important to determine their quality by rapid analysis method.
A small amount of cysts (2-5 cm³) is poured with fresh water in a graduated vessel. If the cysts are of good quality, then the volume of hydrated cysts will double in 1 hour.
Or a small volume of cysts is treated with sodium hypochlorite; you can use a quality solution of “White”. In this case the opaque chorion dissolves and the orange cyst embryos are visible to the naked eye in 15 minutes.
You can also crush a small number of cysts between 2 small glasses and look at them through a magnifying glass: the number of grease spots indicates that the embryos are alive.
1.2. When hatching the Altai cysts, maintain the following parameters:
- warm the cysts for two to three days at room temperature before the incubation;
- the density of cysts shall be 2-2.5 grams per 1 liter of the incubation solution, the salt content is from 15 to 30 grams per 1 liter, the temperature is 25-28 ºC, the illumination and bubbling should be sufficient, the water pH value is about 8. Since the water pH in our country is often much lower, which says about its bacterial contamination and acidity, it is necessary to add 1÷2 grams of edible soda per 1 liter of the incubation solution.
If a large amount of foam forms during the incubation, this indicates the excessive bacterial contamination of the initial raw materials; this fact applies to both dry and raw cysts. In addition, raw cysts are often affected by molds during their storage and smell of penicillin in this case. Such cysts can be treated with 2% formaldehyde solution and washed thoroughly before drying.
After the incubation is completed (in 24 hours), turn off the compressor and bring the lamp to the container for 15 minutes. Nauplii respond well to the light and gather in the middle part of the tank, from where they can be sucked off, for example, with a “suction bellow”. Shells, which have the property of being attracted by a magnet, gather in the upper part of the cone; and non-hatching cysts, sand and other heavy impurities gather in the lower part of the cone. Nauplii brightly colored in orange have the highest energy value, and vice versa — pale nauplii must be enriched in a suspension of some oils. Please, contact Ecofond, LLC to get more detailed information on this issue.
Those nauplii that cannot be fed directly to the larvae should be frozen in ice cubes in the refrigerator freezer.
It is recommended to the beginners to use sodium isoascorbate in volumes up to 20% by weight of incubated cysts as an activator during the incubation of the Siberian cysts. This activator acts more gently than hydrogen peroxide or calcium peroxide. The mentioned activators with a slight overdose kill embryos, but they can have a great effect on the percentage of hatching in case of decrease in dose.
II. DECAPSULATED CYSTS (EGGS)
The decapsulated eggs are of two types:
- with a killed embryo — in this case they are of interest to fish farmers as a source of protein, lipids and some vitamins;
- with an unbroken embryo, from which we can obtain nauplii during the incubation process under the same conditions as with dry cysts. They represent a much more attractive feed for fish and shrimp larvae, since the larva can consume live food in the form of nauplii in the water column.
The decapsulated cysts have several advantages compared to dry cysts:
- they are practically sterile and do not contain any bacteria, fungi and viruses;
- they do not contain the chorionic shell, which can clog the gastrointestinal tract of larvae;
- before feeding, decapsulated cysts (eggs) can be soaked in the solution with the addition of interferon or vetom primer, which are immune modulators. This significantly reduces the larvae mortality.
The disadvantages of decapsulated cysts (eggs) include a significant decrease in vitamin C in eggs compared to dry cysts. The second disadvantage of decapsulated Artemia cysts is that cysts lose the buoyancy quickly and sink to the bottom when fed in an aquarium. But larvae or fry of those fish species that take food from the bottom can use them.
The larvae of carp, silver and bighead carp, grass carp, pelyad and rainbow trout can be fed with decapsulated cysts.
Various feeder designs have been developed in order to provide the decapsulated cysts with a longer buoyancy and to ensure the automation of the feeding process. Please, contact Ecofond, LLC for more detailed description of feeding methods.
Dry decapsulated cysts must be kept in vacuum package in the refrigerator at temperature of 0 ºC to -5 ºC. Freshly hatched nauplii can be kept in containers for storing ice cubes in the refrigerator freezer.