The rearing of adult stingrays in ponds can be optimized by shifting the stocking strategy from traditional fish species to yellow sturgeon fry. This approach helps shorten the breeding cycle, reduce production costs, and achieve higher yields and efficiency. Practical experience has shown that when yellow sturgeon fry measuring 2–5 cm are raised for 6–8 months, they can reach a commercial weight of 80–150 grams per fish, with a yield of approximately 300 kg per 667 square meters, generating around 3,000 yuan in revenue. Below are the key technical guidelines for successful stingray farming.
First, the pond should be carefully selected. Stingrays have low tolerance for low oxygen levels and require a high-quality environment. It is recommended to use a rectangular pond with a steady water supply, clean water, and efficient drainage systems. The ideal area ranges from 2,000 to 4,000 square meters, with a water depth of 1.5 to 2 meters. The pond bottom should be flat and made of loamy soil that allows good aeration, with minimal clay or sand. The sludge layer should be less than 10 cm thick, and the pond must be leak-proof. An independent intake and drainage system is essential, with a 30-mesh screen at the inlet to prevent wild fish from entering, and a wire mesh at the outlet to prevent fish from escaping.
Two weeks before stocking, the pond should be drained, weeds removed, and excess silt cleared. For disinfection, 125–150 kg of quicklime and 1–1.5 kg of crystallized trichlorfon per 667 square meters are applied. After 5–7 days, fresh water is added, and 200 kg of organic manure is introduced per 667 square meters. After 7–10 days, plankton populations increase, creating a suitable environment for young fish.
Yellow sturgeon fry are typically stocked in June, with 2–3 cm seedlings at a density of 3,000–4,000 per 667 square meters, and 4–5 cm seedlings at 2,000–2,500 per 667 square meters. When the fish grow to 7–8 cm, the water becomes more nutrient-rich, and squid fry (8–10 cm) are introduced to help balance the ecosystem. Before stocking, the fish are briefly immersed in a 3% saline solution for about 15 minutes to improve their resistance.
Stingrays are partial omnivores, and younger fish have a higher demand for "fungus" in their diet. Once the fish reach 8 cm in length, plankton is cultivated through fertilization while feeding them animal-based feed such as fish gills. A drumming sound is used before feeding to condition the fish to gather at the feeding station. After one week, the feed is mixed into a dough-like form using squid, mackerel, soft-shelled turtle, or frog, and fed three times daily—morning, afternoon, and evening. Each feeding session lasts about 1–2 hours. As the fish grow to 8 cm, they are gradually transitioned to artificial compound feed. Over 10 days, the proportion of natural feed is reduced, and artificial feed is increased until the fish fully adapt.
The feed formula should include 38–40% crude protein, 7–9% crude fat, 20–30% carbohydrates, and 5–6% fiber. Feeding follows the "Four Sets" principle: fixed time, fixed amount, fixed quality, and fixed location. From June to September, feedings occur three times daily at 7:00 AM, 4:00 PM, and 8:00 PM. After October, feedings are reduced to twice a day—7:00 AM and 4:00 PM. The amount of feed depends on water temperature, water quality, weather, and the fish's appetite. At 10–15°C, feed is 1.5–1.8% of the fish’s body weight; at 15–20°C, it increases to 2–3%; and at 20–32°C, it reaches 4–5%.
Water quality management is critical. During the early stages, the water level should be maintained between 70–80 cm to promote temperature rise and plankton growth. Later, the depth is increased to 1.5–1.8 meters. Fertilization is adjusted based on fish size—plankton is maintained when the fish are under 8 cm, and feeding takes priority afterward. Water transparency should be kept at 20–30 cm for smaller fish and 30 cm for larger ones, with dissolved oxygen above 4 mg/L. New water is added every 10–15 days, more frequently during hot seasons, with each change ranging from 15–30 cm. Lime (20 g/m³) is sprinkled every two weeks to maintain a pH of 7–8.4, and bleaching powder (2 kg/10 m²) is used periodically to disinfect the water. An aerator of 1.5 kW is installed to ensure sufficient oxygen, and its usage is adjusted according to weather and water conditions.
Disease prevention is crucial. Regular disinfection of water, food areas, and live bait helps maintain a healthy environment. Common diseases include enteritis and hemorrhagic edema. To prevent enteritis, 1% salt or garlic juice is added to the feed. During treatment, 1 g of bleaching powder per cubic meter is used, combined with sulfamethoxazole in the feed. On the first day, 10 g per 100 kg of fish is given, then halved the next day and continued for six days. For hemorrhagic edema, 0.3 g of strong chlorine essence per cubic meter is applied daily for three days, along with 0.6–0.7 g of tetracycline per kg of feed, also for three days.
Since stingrays lack scales, they are more sensitive to aquatic drugs. The 24-hour half-lethal concentrations of common drugs are: copper sulfate 0.69 mg/L, 90% crystal trichlorfon 2.8 mg/L, salt 25 g/L, and formalin 68 mg/L. Therefore, drug dosages must be strictly controlled to avoid poisoning.
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