Personal Protective Equipment,hooded coverall with shoecover,hydrogel undereye patch Shandong Zhushi Pharmaceutical Group Co.,LTD , http://www.sdzs-medical.com
Channel fork tail, seed size breeding and catching
The punctuated tail fish is known for its delicious flesh and rich nutritional value, especially due to the absence of intermuscular punctures. This makes it highly desirable in both domestic and international markets, offering great potential for processing and export. However, there is currently a shortage of raw materials for processing companies, which has created a demand gap. The species grows rapidly, reaches large sizes, has a varied diet, strong disease resistance, and high catch rates, making it well-suited for a wide range of water temperatures. These traits have made it popular among both consumers and farmers.
In recent years, as a new breed has been rapidly promoted, the supply of seedlings has become the main bottleneck in breeding. Based on the author’s practical experience, the key techniques for seedling production are outlined below.
First, artificial reproduction of fry:
1. Broodstock Selection: Choose broodstock aged 3 to 5 years with a body weight between 2.5 kg and 3.5 kg. During the non-breeding season, males have slightly wider heads and darker bodies, while females have narrower heads. During the breeding season, males develop larger muscle tumors on their heads, and their gonads show papillae. Their abdomens are stiff and hard to bend, while females have soft, inflated bellies with a round, concave genital opening. The male-to-female ratio should be maintained at 3:2.
2. Broodstock Cultivation: The pond area should be around 2,500 square meters with a water depth of about 1.5 meters. Stocking density is 20–30 per 667 square meters. When the water temperature exceeds 13°C, special feed is introduced. At 21°C or above, the feeding rate is 2% to 4%, supplemented with animal-based feeds like boiled small fish and shrimp, and plant-based feeds such as malt extracts. Rinse the broodstock every 10 days to stimulate gonad development.
3. Artificial Oxytocin Promoters: Commonly used hormones include carp pituitary (PG), human chorionic gonadotropin (HCG), and luteinizing hormone-releasing hormone analogues (LRH-A). For each kilogram of female fish, administer 4–6 mg of PG, 1000 IU of HCG, or 2–2.5 mg of LRH-A. Males receive half the dose.
4. Fish Nest Setup: Use plastic buckets, iron buckets, or wooden boxes as nests. One end is open for broodstock to enter and exit, while the other is covered with nylon cloth. After spawning, the nest is placed on the pool bottom at a depth of 0.5–1 meter, facing the center of the pool. A float is attached for easy location. Nests are spaced 9–10 meters apart, and they account for 50% of the broodstock.
5. Egg Collection: When the water temperature is above 21°C, check the nests daily from 10 AM to 11 AM and drive off the broodstock. If eggs are present, gently remove them and place them in a smooth barrel filled with pool water.
6. Hatching Conditions: Fertilized eggs hatch within 110–120 hours at 25–29°C. It takes about 10 days for larvae to develop into juveniles. Eggs can be hatched naturally in ponds or using hatching tanks. Incubation requires a water temperature of 25–28°C, pH 6.5–8.0, dissolved oxygen of at least 6 mg/L, and a water exchange of about 20 liters per minute.
7. Disease Prevention: To prevent water mold, alternate between mildewin and formalin. Before the eggs turn red, apply either 60–65 mg/L of mildewin for 10–12 minutes or 100 mg/L of formalin for 4–10 minutes.
Second, summer flower fish breeding:
1. Pond Conditions: Summer flower nurseries require good water quality, easy access to water, flat and clean bottoms, and sturdy structures without leaks. The nursery pond is typically around 667 square meters, while the breeding pond ranges from 2001 to 3335 square meters with a depth of 1.3–1.6 meters. Each pond should have an aerator (1.5 kW or 2.5 kW) and a pump.
2. Pond Disinfection: Before stocking, drain the pond, remove excess silt, let the bottom dry for 20 days, then refill with 10 cm of water. Apply quicklime (75–100 kg/667 m²) to disinfect.
3. Water Preparation: Ten days before stocking, filter the water to a depth of 0.6–1 m. Add fermented organic manure (100–500 kg/667 m²) to increase natural plankton for food.
4. Stocking and Growth: After 3–4 days, fry grow to 4–5 cm. Stock 30,000–50,000 fry per 667 m². After 20–30 days, transfer to breeding ponds. Stock about 50g fish per 667 m², with 8,000–9,000 summer flowers and 600–700 squid per 667 m².
5. Feeding: Feed for 4–5 days after stocking, starting with zooplankton. Once fry reach 4.5 cm, switch to compound feed. Use sound cues to train fish to eat in groups. Feed twice daily at 3–5% of body weight.
6. Daily Management: Maintain dissolved oxygen above 3 mg/L, pH 6.5–8.3, and replace 10% of the water every 7–10 days. Gradually increase water depth to 1.5 m. Use chlorine dioxide (0.5 mg/L) to prevent diseases.
Third, seed fishing and transportation:
1. Seed Fishing: Catch summer flowers in the early morning or late evening when water temperatures are lower. For air transport, catch the day before and keep them in a seedling box overnight.
2. Transportation: Perform 2–3 net exercises before transport. Use 30cm×30cm×40cm nylon bags with 3–4 L of water, holding 1500–3000 fish per bag for 12–18 hours. Pack in cardboard boxes to prevent damage. Re-oxygenate or change water during long trips.
3. Fingerling Catching: Catch fingerlings from November to April. Conduct at least two net exercises and stop feeding for 2 days, followed by 3 hours of water flushing.
4. Fingerling Transport: Use oxygenated nylon bags with no more than 0.5 kg per bag. Place fish in oyster-shaped containers lined with smooth nylon to avoid injury. Supply pure oxygen and maintain a density of 30 kg per cubic meter of water.