Sturgeons belong to the Acipenseridae family, which are also known as living fossils due to their antiquity. These fish are divided into 27 species and subspecies in the world.
The world’s top five species of sturgeon include the Huso huso or Beluga, the Russian sturgeon or Chalbash (Acipenseridae gueldenstaedtii), the Persian Sturgeon or Ghara Boron , the Acipenser nudiventris sturgeon, and the Ozone Boron (starry sturgeon ) fish or Suruga are the main types in the Caspian Sea.
For the purpose of caviar extraction and the sturgeon meat, Sturgeon breeding is done in warm waters and in earthen ponds as well as in concrete and fiberglass ponds. The species reared in Iran are Acipenser ruthenus (Volga Sterling) and Huso huso (phylloxera). Since the growth of sturgeon is so slow, it is very important to choose the right food with the right level of energy and to provide all the necessary factors for fish growth in various climatic conditions of the country in accordance with the schedule of breeders. This not only can stop wasting time bot also it prevents reducing growth of the fish.
The advantages of using extruded feed are:
- A balanced protein / fat ratio provides the best growth rate.
- Appropriate conversion coefficient due to slow growth of sturgeon.
- Improving the natural immune response of fish to diseases due to its stimulants.
- Proper feed density and long period of immersion and falling into the water column, which results in maximum use of the given food.
- Zigzag movement of the food during the fall makes it visible to the fish.
- Using the highest quality raw materials to prepare this type of food.
- Proper consistency and stability and non-rupture of feed grains even after reaching the substrate reduces the pollution of the breeding environment
It is essential to determining the appropriate and desirable percentage of feeding in order to achieve maximum growth and high profitability. The percentage of feeding varies according to body weight at different temperatures. The best suggestion and method for proper nutrition is to control the Factor of Conversion Ratio (FCR), Biomass Weight (BW) and Coefficient of Fat (CF).
The amount of daily food is determined by the temperature, weight and number of fish and should be calculated every 5-10 days. The average weight is determined every 5 days with the start of external feeding. The amount of fish should be determined by deducting losses. Changing the feed size to a larger size should be done gradually and by mixing it with the previous feed size. After each feeding, the consumed food should be checked in the tank. If a large amount of food is not eaten, the diet and fish breeding conditions should be checked. The amount of daily food should be adjusted after distinguishing the cause of poor nutrition of the fish..