The selection of broodstock should be made from the previous year’s 9th to 10th month or from March to April of the current year. The selected individuals must be over 10 months old, with a weight between 30 and 50 grams. They should have fully developed appendages, a strong and healthy physique, no signs of disease or injury, smooth skin without any attachments, and good mobility. The male-to-female ratio should be maintained at either 2:1 or 1:1. Male and female crayfish can be easily distinguished by their physical characteristics. Mature males are generally larger than females of the same age. For shrimp of similar body length, males have larger chelipeds with bright red soft ticks on the outer side, while females have smaller chelipeds and rarely have these soft ticks, if present, they are lighter in color. Males have reproductive pores located at the base of the fifth walking leg, whereas females have theirs at the base of the first three legs. Female abdomens become enlarged when sexually mature, while males have narrower abdomens.
Broodstock rearing tanks are typically earthen ponds, with a width of at least 1.5 meters and a water depth of 0.5 to 1 meter. A drainage system is essential, and the pond edges should be lined with plastic film or calcium boards to prevent escape. The water must be clean, well-oxygenated, and free from pollution. During intensive breeding, dissolved oxygen levels should remain above 4 mg/L. Small ditches are dug in the pond to facilitate shrimp collection. Fifteen days before stocking, the entire pond is disinfected using 150 kg of lime per day, and 500–800 kg of decomposed livestock manure is added for fertilization. After filtering to prevent wild fish from entering, fresh water is introduced. Branches, tree roots, bamboo tubes, and aquatic plants are placed in the pond to provide shelter and climbing areas. Aquatic plants should cover about one-third of the pond area.
The stocking density for broodstock is usually 100–150 kg per mu for those selected in September–October, and 80–100 kg per mu for those selected in March–April. Before stocking, the shrimp are bathed in a 3% saline solution for 10 minutes. During cultivation, feed such as fresh grass, soybean cake, wheat bran, or compound feed is provided, along with some animal-based food like chopped snail meat or leftover meat from slaughtered animals. Feeding amounts vary depending on the season: 2–3% of body weight in March, 4–5% in April, and 6–8% in May. Feedings are done once daily, with 70% given in the evening. Water quality management is crucial, with regular water changes every 10–15 days, replacing 1/3 of the water each time. Quicklime (20–25 g per cubic meter) is added to maintain good water quality and support gonad development.
Reproduction begins from April to May when the water temperature reaches 18°C. Males transfer sperm into the seminal vesicles of females before spawning. Fertilized eggs hatch into juvenile shrimps on the setae of the female’s abdomen. Incubation takes place at 22–28°C, with hatching times varying based on temperature: 30–40 days at 18–20°C and 15–20 days at 25°C. Juveniles grow under maternal protection and become independent after leaving the mother. When large numbers of juveniles are observed, they should be harvested promptly.
For seedling cultivation, small pools of 20–40 square meters or earthen ponds of 1–3 acres with a 1:2 slope and 0.5–1 meter depth are suitable. These ponds must have good water flow, proper filtration, and anti-escape structures. After sterilization, 500 kg of cooked manure is applied per mu to promote natural food growth. Roots, bamboo tubes, mesh sheets, and submerged or floating plants are added for shelter. Juvenile stocking density is typically 150–230 per square meter, with uniform size and best stocked during sunny mornings or cloudy days.
In the first week, grated soy milk is fed 3–4 times daily. From the second week onward, feeding shifts to animal-based foods like small fish, snails, and crushed plant matter. Feed amounts start at 0.25–0.40 kg per 10,000 shrimp and gradually increase to around 10% of the shrimp’s body weight. Adjustments are made based on weather, water quality, and consumption rates. Water is changed every 7–10 days, with 1/3 of the water replaced each time. Dissolved oxygen levels must stay above 5 mg/L. Every 20 days, 20 g of quicklime per cubic meter is sprinkled to improve water quality and provide calcium for shell development. After 25–30 days of cultivation, the larvae grow 5–8 times and reach 3 cm in length, ready to be transferred to shrimp ponds for further culture.
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