The deep-water soilless cage aquaculture project, led by the Hubei Yuan'an County Agricultural Technology Center, has successfully passed its acceptance inspection. The initiative involved cultivating 200 square meters of astragalus (a type of aquatic plant) using a soilless cage system. The results were impressive: an average yield of 13.64 kg per square meter, with a production value of 625.5 yuan per square meter and a profit of 280 yuan per square meter. Below are the key technologies implemented in this high-yield and high-efficiency aquaculture model.
1. **Cage Design**: The cages are rectangular, with areas ranging from 15 to 100 square meters, and their length is more than three times their width. The total height of each cage is approximately 1.5 meters, meaning that the water depth inside is around 0.5 to 0.7 meters, while the outlet water level is 0.8 to 1 meter. The cages are constructed from polyethylene mesh with a mesh size between 0.8 mm and 1.2 mm, and the upper and lower ropes have a diameter of 6 mm.
2. **Cage Placement**: These net cages are installed in sunny, clean, and quiet waters such as ponds, rafts, rivers, lakes, and reservoirs with stable water levels. When setting up the cages, the supporting bamboo rafts must be securely fastened, and the surrounding steel ropes should also be tightened. Each corner of the cage is filled with a 25 kg bag of yellow mud, pressed against the bottom to ensure that the mesh above and below the cage remains perpendicular to the water surface or the lakebed.
3. **Plant Transplantation**: Astragalus thrives in environments with floating aquatic plants. Fast-growing species like water peanuts and water hyacinths are ideal for this purpose. For planting, one-third of each end of the cage is reserved for a 20- to 30-cm floating row, leaving the middle third open. The process involves straightening the vines on the shore, piling them up, and then using 5 iron forks to place the plants vertically into the cage. Approximately 25 kg of plants can be placed per square meter.
4. **Stocking Strategy**: After soaking the plants for 10 to 15 days, quail (or other suitable aquatic animals) can be introduced when the water temperature is between 18°C and 20°C during the day. The quail should be wild-caught, healthy, and active, with each individual weighing between 30 to 40 grams. Before stocking, they are sterilized in a 2% to 3% saline solution for 5 to 8 minutes. Stocking density depends on the area of the floating plants, typically 2 to 2.5 kg per square meter.
5. **Feeding and Domestication**: Two to three days after stocking, the quail are fed with animal-based feeds like fish, shrimp, or meat. A pre-dose feeding plan is followed, starting with a 9:1 ratio of fish paste or clam to compound feed. Over 4 to 5 days, the proportion of compound feed is gradually increased to 60%–70%, while animal feed makes up 30%–40%. For every 100 kg of astragalus, 5–6 kg of feed is provided daily, ideally in the evening, directly onto the aquatic plants.
6. **Daily Management**: To manage waste and dead organisms, the "push-out method" is used—pushing the floating plants from one end to the other. This allows for easy cleaning and inspection without disturbing the entire setup. If needed, the floating rows can be moved to the other side, and the middle section can be returned to its original position for regular checks.
7. **Disease Prevention and Treatment**: With proper hygiene and regular disinfection, disease occurrences are minimal. Disinfection is done every 20 days using 25 mg/L quicklime or 1 mg/L bleach. Deworming is conducted every 40 days using 0.45 mg/L trichlorfon. In case of enteritis, 5 g of oxytetracycline or sulfamethoxazole per 100 kg of astragalus is administered for 5–7 days. For bleeding conditions, 2.5 g of fluoctonic acid per 100 kg of astragalus is used for 5–6 days.
8. **Wintering Methods**: This aquaculture system cannot survive the winter, so all astragalus must be harvested before the end of December. If storage is required, the plants should be transferred to a special wintering pool in late autumn. A 3-meter-square, 1-meter-deep earthen pond is prepared for every 50 kg of astragalus. The original cage is placed in the pool with 20–30 cm of soil, and the plants are soaked in water for 2–3 days. After 10–15 days of drainage, the pool is slowly emptied. At the start of frost, straw and thatch are added to the pool to protect the astragalus through the winter.
Xuzhou Guifeng Metal Technology Co., Ltd , https://www.guifengmetal.com