The red crabs are female crabs that have been mated and fertilized. They began to be stocked in October in the intensive breeding pool. When the ovary of the serrata crab is fully mature, the carapace is filled with red ointment on both sides. The breastplate expands and the dots above the abdomen become red. When the whole carapace is brown or reddish brown, it is called "Red Crab". At this time, it is harvested and listed. The benefits are very significant before and after New Year's Day.
I. Crab pool construction
The area is generally about 333 square meters. The wall of the pool is about 1 meter high with slate or brickwork. The pool wall is generally surrounded by anti-escape and covered with coarse sand or gravel. The bottom of the pool is best to be paved with slate. Tighten the groove without leaving a groove, and then apply 10 cm to the slate.
Second, the stocking density
In general, 2000 amphibious intensive breeding ponds and over 250 grams of mating crabs have been mated.
Third, feed the bait
Feeding fresh fish, shrimp, shellfish and other animal feed, the amount of feeding is 5% to 7% of the total weight every day, and the feeding should be fixed, and less investment in the morning (about 20% of the total amount of feed). Investment (70%-80% of the total amount of feed). When the water temperature drops to 10°C, feeding should be stopped.
IV. Grading
The ovarian development of female crabs was inspected in a timely manner to distinguish the quality grades (according to the degree of ovarian development, they could be divided into “motherâ€, “crab†and “paste crabâ€) for grading.
V. Adjust water quality
The water depth is only 30-60 cm, and the water exchange volume must be increased to maintain adequate dissolved oxygen. Change the water twice a day and install a water pump. At noon and at 4-5 o'clock in the morning, do not pump in fresh seawater. During the infusion, blue crabs often compete for fresh water, and bamboo rafts are used in time. They are separate.
VI. Disease Prevention
The oyster shell is a common disease of female crabs that have been mated and fertilized. The experimental observation of the hardening time of the mating female crabs was as long as 2-3 days, resulting in highly susceptible pathogens; the oxygen consumption of mating female crabs increased, and the female crabs were susceptible to hypoxia. And suffocation died. Prevention methods. 1. Improve the water environment, make the water clear, and maintain a certain degree of salinity (greater than the relative density of seawater 1.005). 2. Take aerators to increase oxygen or pump water to increase oxygen. 3, do not feed deterioration, moldy food. 4, with antibiotics regularly by 0.5 to 1ppm Quanchiposa. 5. The diseased crab should be caught in time. At the same time, 2-3PPm bleach can be used for water disinfection to prevent the spread of disease.
Seven, timely fishing
Every 5-10 days, check the development of blue crabs and find that “red crabs†are selected and sold in time. If you do not catch fish in time until March of the following year, you can only sell it as a "vegetable crab."
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