Detailed Explanation of Key Points of Artificial Breeding Technology for Paddlefish

This fish is the easiest to raise, very hardy, but first you need to pay attention to the oxygen content of the water, and second you need to pay attention to its food. It mainly eats plankton, and tap water definitely won't work. You also have to cultivate food for it, which is quite troublesome. Using soybean milk to cultivate it works. Breeding technology for paddlefish

1. Fry rearing

Generally, the trough method is used for rearing fry. After hatching, they are reared in troughs for 30~40 days until they reach 3~5 cm and are then transferred to ponds. This process is the key to fry survival.

(1) Trough conditions: an area of about 10 sq m, either rectangular or circular, with no sharp corners, convenient water inlet and drainage, and anti-escape facilities. The water quality must be excellent, without purification or toxic hazards, and it must be filtered before use. Water exchange should be carried out 2 times per hour (stop water for half an hour during feeding). The water temperature should be between 16~28°C, and dissolved oxygen should be above 5 mg/L.

(2) Stocking density of paddlefish fry: at the beginning, 200 fish/sq m, and when they grow to 5 cm, the density is reduced to 100 fish/sq m.

(3) First-feeding bait and feeding: The first-feeding bait for paddlefish is zooplankton, and a combination of egg yolk and zooplankton can also be used. The best first-feeding bait for paddlefish is cyclopoid copepods. If feeding Cyclops, the timing must be well controlled to prevent Cyclops from piercing the fry's yolk sac, causing mass mortality of the fry. The suitable number of daily feedings is 4~8 times; indoor rearing also requires feeding at night, and the amount should be slightly in excess. The bait initially put in must pass through a 60-mesh sieve to remove large individuals and harmful aquatic insects. Later, after domestication, they can consume wild compound feed, with intake at about 30% of body weight. Paddlefish have very poor eyesight and will not actively seek food, so the amount consumed during feeding will be somewhat larger.

(4) Daily management and precautions: Daily management requires sewage removal, scrubbing screens, and keeping detailed records. When the fry grow to 3~5 cm, several abnormal conditions occur, such as gathering in the corners of the trough, biting and swallowing each other, and uneven individual sizes. The causes of these conditions are uneven nutrition and excessive density. In addition, due to insufficient nutrition, the fry will also swallow air bubbles on the water surface, causing the digestive tract to swell and bleed until death. About 80% of fry deaths are caused by biting and swallowing each other, and about 20% are caused by congestion of the digestive tract. Therefore, fry after 3~5 cm should be stocked into ponds with balanced and sufficient food and a larger water body

2. Pond rearing of fingerlings

Fry of 3~5 cm are reared in the same year into large-size fingerlings with a body length of 20~30 cm and a body weight of 200 g, which takes 3~4 months.

(1) Pond requirements: ponds with a water surface of 3~5 mu, a water depth of 1.5~2 m, and convenient water inlet and drainage are better. Each pond should be equipped with one 1.5 kW aerator. Before stocking, the pond must be cleared with water, using 150~200 kg of quicklime per mu to kill miscellaneous fish, aquatic plants, and so on. The pond water temperature can be 2~37°C, with the optimum at 25~32°C.

(2) Stocking after fertilizing the water: One week before stocking, fertilization should be carried out to cultivate good water quality. The fertilizers are generally human feces (400~500 kg/mu) and chicken, cattle manure, etc. After 3 days, soybean milk is spread into the pond at 5 kg/mu. Before stocking, the water flower net should be used to fish once more to remove tadpoles and debris. The temperature difference between the pond water and the water in the fish container must not exceed 3°C, and the operation should preferably be carried out in the evening.

(3) Reasonable sparse stocking: The main farming method is monoculture, and it can also be polycultured with a large number of bottom-dwelling fish and herbivorous fish. Do not polyculture with silver carp and bighead carp or aggressive fish. The stocking density is preferably 100 fish per mu. During the farming process, in addition to fertilizing to cultivate the water body, soybean milk (2 kg/mu), cake meal, floating wheat flour, bran, or special pellet feed must also be fed. The water quality must always be maintained as fertile, lively, tender, and refreshing.

(4) Strengthen management: Persist in patrolling the pond every day and carefully keep farming records.

(5) Fish diseases and treatment: Generally, fingerlings over 10~15 cm rarely die, but there have been several reports of parasitic and bacterial diseases. Because paddlefish are very sensitive to drugs, especially heavy metal salt drugs, caution is required when using medication. Occasional fish diseases are mainly nematodes and trematodes, and a bath with 2 10-6 potassium permanganate or less than 75 10-6 formalin can be used. During the juvenile stage, copper sulfate and chlorine-containing drugs are prohibited, and the soaking concentration of antibiotics is about 4 10-6. After being raised into large-size fingerlings of 30~40 cm, they can be directly released into reservoirs, or they can continue to be cultured in ponds.

3. Release

(1) Size: 30~40 cm or larger, to ensure their ability to live and defend against other aggressive fish.

(2) Density: extensive type (that is, stocked by people and raised by nature) 0.1~1 fish per 10 mu; intensive type (small reservoirs, lakes, reservoir bays, etc. of 1,000~5,000 mu, where wild fertilization can be used) 3~5 fish per 10 mu. Because paddlefish are docile, have a short food chain, and have abundant food sources, no additional input is needed, and there is no need to reduce the normal stocking amount of other fish, so there is no impact on the overall consumption.

4. Pond farming of adult fish

(1) Farming methods: Both monoculture and polyculture can be used, with polyculture as the main method, and the mixing ratio depends on local specific conditions. Generally, silver carp + herbivorous fish : sturgeon = 6~7:1; herbivorous fish : silver carp = 1:1.5~3. Regardless of monoculture or polyculture, silver carp must be included, because silver carp can control the number and growth rate of algae and avoid eutrophication of the water body.

For more farming technology, please visit (Sichuan Farming Network http://m.yuhvv.cn)