The broodstock for black spiny barb breeding should be at least 3 years old, with a body weight of 750 grams or more. The fish must be healthy, robust, and free from any disease or injury. During the breeding season, males display light yellow, thick star-like markings on their pectoral fins, while females may also show similar patterns but less frequently. Mature males have a soft, milky white abdomen, while females have a slightly swollen and soft belly, with a reddish reproductive pore visible. Their ovaries can often be seen as distinct contours in the abdominal area. Broodstock for artificial propagation can be collected from wild fish caught in rivers before the breeding season. It is important to ensure the fish are in good health and undamaged. Alternatively, broodstock can be selected from commercially raised fish that have been carefully cultivated and maintained in intensive conditions. These farmed individuals usually respond better to hormonal stimulation. For broodstock cultivation, black spiny barbs can be raised either alone or in polyculture with other species like silver carp, grass carp, and common carp. The breeding area should be around 0.2–0.3 hectares, with water depth between 1.5 and 2.0 meters. A steady supply of clean, fresh water is essential, along with proper drainage and irrigation systems. Stocking density is typically 1,500 to 1,800 fish per hectare, with 5–10% of the population consisting of species like clams, snails, and grass carp to help maintain water quality. High-quality compound feed with over 32% crude protein is recommended, supplemented with green feed to avoid excessive growth that could interfere with spawning. One month before hormone treatment, frequent water flushing helps stimulate gonad development. Artificial ovulation usually begins in late May when water temperatures stabilize above 20°C. Female fish are injected with LRH-A2 (15–20 μg/kg) or HCG (1,200–1,500 U/kg), sometimes combined. Two injections may be used depending on maturity. Poorly matured fish can be treated earlier with 1–2 μg/tail of LRH-A2. Injection volume is 2–3 mL per fish, typically administered via thoracic injection. A 1:1 ratio of male to female is ideal, allowing for either natural spawning or artificial insemination. At 20°C, the effect lasts 25–30 hours, while at 21–28°C, it takes 10–20 hours. For artificial hatching, eggs are large and expand quickly after absorbing water, reaching diameters of 2.5–3.3 mm. Fertilized eggs are placed at a rate of 400,000–50 million per cubic meter. The hatching water must be clean, and a fine mesh filter is used to prevent harmful organisms from entering. Water flow is maintained during incubation, and dead eggs are removed promptly to prevent fungal infections. Optimal hatching occurs at 22–28°C. At this temperature, larvae hatch within 65–115 hours, measuring 7.3–8.4 cm in total length with an orange yolk sac. After 3–5 days of free swimming and active feeding, fry are moved to ponds for further cultivation. The temperature difference in the pond should not exceed 2°C. Fry cultivation typically takes place in cement or small earthen ponds. Cement pools, ranging from 50–100 square meters, are easier to manage, with a stocking density of 50–100 fish per square meter. Shade nets are used to reduce light intensity. Earthen ponds can hold 1.2–1.5 million fry per hectare, which are transferred to fingerling ponds once they reach 2.0–3.0 cm. Fish ponds or cages are used for larger-scale breeding, with pond areas between 600–2000 square meters and depths of 1.5–2.0 meters. Cage sizes vary, with mesh sizes of 0.8 cm, 1 cm, or 2 cm. Stocking densities range from 450,000 to 500,000 per hectare in ponds, and 2,000 per square meter in cages, with gradual reductions as fish grow. After about 30 days, fry typically reach 4.5–6.5 cm in length. Fish breeding often involves polyculture. Fry measuring 4.5–6.5 cm are stocked at 120,000–180,000 per hectare, growing to 8–10 cm. In the next stage, fish reach 12–16 cm, with a stocking density of 75,000–90,000 per hectare. Some fry are raised in cages at 2.5–3.5 cm, then transferred to ponds or reared sparsely until they reach 3–4 cm. Black spiny barbs are fed a balanced diet, including commercial feeds, rice bran, wheat bran, alfalfa, snails, and natural bait. Green vegetables like lettuce and rotifers are also provided to supplement vitamins and support healthy growth.

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