Home › Livestock Farming › Article

Case study of silver carp and bighead carp cage culture

Livestock Farming 0 views
How many fish to stock in a cage is reasonable and correct should be determined according to the location and specific conditions. Generally speaking, in flowing water and in cages with high dissolved oxygen in the water, more can be stocked. In places with stable water, little wind and waves, and low oxygen in the water body, fewer can be stocked. In other words, the limit of stocking is when the oxygen in the cage can fully satisfy every fish. If the oxygen cannot meet the needs of the fish, it means the stocking is excessive. In fertile water (transparency of 25-30 cm), raising silver carp and bighead carp requires no feeding. Overall, the stocking amount can be based on the following

How many fish to stock in a cage is reasonable and correct should be determined according to the location and specific conditions. Generally speaking, in flowing water and in cages with high dissolved oxygen in the water, more can be stocked. In places with stable water, little wind and waves, and low oxygen in the water body, fewer can be stocked. In other words, the limit of stocking is when the oxygen in the cage can fully satisfy every fish. If the oxygen cannot meet the needs of the fish, it means the stocking is excessive. In fertile water (transparency of 25-30 cm), raising silver carp and bighead carp requires no feeding.

Overall, the stocking amount can be determined according to the following data: per square meter, stock 250 fish of 4 cm body length at a ratio of 2 silver carp to 3 bighead carp (2:3); raise them for 45 days and 38 days respectively, and they can grow to 13.3 cm in length. Per square meter, stock 300 fish of 4 cm body length at a ratio of 3 silver carp to 1 bighead carp (3:1); raise them for 54 days and 57 days respectively, and they can grow to 13.3 cm in length. Per square meter, stock 400 fish of 4 cm body length at a ratio of 4 silver carp to 1 bighead carp (4:1); raise them for 67 days and 48 days respectively, and they can grow to 13.3 cm in length. Per square meter, stock 500 fish of 4 cm body length at a ratio of 5 silver carp to 1 bighead carp (5:1); raise them for 96 days and 39 days respectively, and they can grow to 13.3 cm in length.

The above reference data show: (1) When the stocking ratio of silver carp to bighead carp is 3:1, their growth rates are similar; at 5:1, bighead carp grows faster. (2) When 250 fish are stocked per square meter, their growth rate is 1 times faster than when 500 fish are stocked. Farmers can determine the stocking amount according to the size of the fry, the breeding goal, and differences in dissolved oxygen and food in the water. The reference stocking amount is 200-400 fish per square meter, and small cages are preferable.

Site selection: Choose a place with abundant plankton in the water body, with a plankton biomass of 18.4 mg/L (biomass contained per liter). Water with this biomass often has a transparency of 120 cm, which by conventional standards is already considered not fertile water. If cages are placed, feeding cages and non-feeding cages should be placed alternately; it is not advisable to place only non-feeding cages. When arranging them, they must not block the flow of water for each other. If the water quality transparency is about 40 cm, non-feeding cages can be placed throughout, but the spacing between cages must be maintained. When the draft is within 2 m, a smooth flow rate should be maintained, and there should be wind and waves with sufficient dissolved oxygen for the fish to grow well. Plankton must be abundant for silver carp and bighead carp to eat comfortably. Smooth flowing water and sufficient dissolved oxygen, keep distance and do not block each other.

Related Articles