CATDOLL : CATDOLL: Under what temperature do mandarin fish eat?

Mandarin fish is also known as sweet-scented osmanthus fish, belonging to the genus Siniperca of the family L. It has a relatively high and laterally flattened body with a bulging back. It has a large mouth, with the lower jaw significantly longer than the upper jaw. There are small teeth of varying sizes on the upper and lower jaws, the vomer, and the operculum. The rear edge of the preoperculum is serrated, with four large spines on the lower edge; there are two large spines on the rear edge of the postoperculum. The head is scaly, and the scales are small; the lateral line bends upward along the dorsal arc. The dorsal fin is divided into two parts, connected to each other, with hard spines in the front and soft fin rays in the back. The body is yellow-green, the abdomen is grayish white, and there are irregular dark brown spots and patches on the sides of the body; there is a narrow black stripe from the tip of the snout through the eye socket to the front and bottom of the dorsal fin.

Mandarin fish breeding technology

The types of bait fish for osmanthus fish in ponds include silver carp, bighead carp, dace, wheat dace, Thai dace, crucian carp, carp, etc. The bait coefficient is generally 4 to 5. According to the growth specifications and food intake of osmanthus fish, a pond 3 to 4 times larger than the area of ​​osmanthus fish pond is used to cultivate and produce sufficient bait fish to feed osmanthus fish.

1. Early bait fish: 1-2 million fish fry (fish flowers) of silver carp, bighead carp, ling, wheat ling, Thai ling, crucian carp, etc. should be stocked per mu in the pond where osmanthus fish is to be stocked as early bait fish for osmanthus fish. Feed them with coarse feed such as peanut bran and wheat bran. After 15-20 days of cultivation, when the bait fish grow to 1.5-2.5 cm in length, use 0.7ppm copper sulfate and 0.5ppm strong chlorine to kill insects and disinfect, and then put in 2-3 cm osmanthus fish fry for cultivation.

2. Mid-term bait fish: 200,000 to 300,000 fry of local carp, wheat carp, Thai carp and other fish can be raised per acre in the four major carp ponds. You can also cultivate silver carp, bighead carp, crucian carp and other fish fry in special ponds as bait fish for large-sized osmanthus fish.

3. Late-stage bait fish: In addition to self-production and self-sufficiency, you can also purchase from outside. In the late stage of breeding, it is generally winter, and the bait fish of the dace are easy to freeze to death. You should cultivate and prepare some cold-resistant species such as silver carp, bighead carp, and crucian carp to overwinter and use them as backup bait fish for osmanthus fish in winter and spring.

Now is the best season for stocking mandarin fish. The key points of pond culture technology are introduced as follows:

1. Pond conditions: The pond area is generally 2-4 mu, the water depth is about 2 meters, it is mainly rectangular, the water quality is fresh, there is little or no bottom mud, and the drainage, irrigation and oxygenation equipment are complete.

2. Cultivation of bait fish: Based on the principle of good palatability and low economic cost, silver carp, white carp, bighead bream, silver carp, bighead carp and other fish fry can be selected as bait fish. Use the idle period before stocking the sweet-scented osmanthus fish pond to cultivate early bait fish. You can breed crucian carp or bream fry yourself, or you can put various fry about 20 days before the release of sweet-scented osmanthus fish. The stocking amount per mu is 400,000 to 600,000. The feeding method is to feed with soybean milk or other feed. The bait fish in the middle and late stages must be raised in special ponds. It is advisable to adopt a multi-pond high-density breeding method, catch them in batches, and gradually loosen them to ensure that the bait fish grow synchronously with the sweet-scented osmanthus fish.

3. Stocking of Mandarin fish: The stocking time is generally in June, and the stocking size is required to be 6-10 cm. The advantage is that the survival rate is high and the growth rate is fast. Generally, the stocking amount per mu is 500-800 fish.

4. Feeding of bait fish: During the breeding period of adult fish, it is advisable to ensure that they are full every day. If there are too few bait fish and they are hungry, it will affect the growth of mandarin fish or cause cannibalism.

5. Water quality control: The water quality of the mandarin fish pond should be well controlled and water should be changed frequently. The high temperature season from June to September is the peak feeding season. The water should be filled and drained once a week, with 0.4 cubic meters of water changed each time, and the transparency of the pond water should be kept above 40 centimeters.

Tips for stocking mandarin fish

1. Sources and fishing of fish species

1. Source of fish species. Now is the hot season, the temperature is very high, and the fish species are weak, which is generally not convenient for long-distance transportation. The source of supplementary fish species is mostly solved by local adjustment, or they can be caught in natural waters nearby. The fishing site of the fish species is required to be very close to the stocking site, and the fishing and stocking should be closely connected. The fish species should not be out of water for too long, and it is best to catch and stock at the same time. If it is not possible for the time being, you can temporarily raise them in a net cage or stop them in a dragnet for operation, but the time should not exceed two hours. It is strictly forbidden to operate fish species out of water.

2. Fishing of fish species Fishing and raising of fish species should always adhere to the principle of catching quickly and releasing lightly. When fishing, you must be careful and operate slowly, and try not to hurt the fish. The fishing time can be determined in the morning and evening when the weather is cool. Fishing tools should be large drag nets, set nets, etc. that do not hurt the fish. When fishing in the same water body, the number of times the net is pulled should not be too many, otherwise the fish will float to the surface and die. Wire nets will hurt the fish and cause fish scales to fall off, so do not use them. Fishing in dry ponds will choke the fish to death with sewage, and will also burn the fish due to shallow water, so it is best not to use it. For carnivorous fish, you can use medicated bait to lure them when feeding, intercept the nets on their activity routes, and capture them in a concentrated manner. This is also a good fishing method.

2. Stocking and management of fish species

1. Preparation before stocking Before stocking, various preparations should be made, and the inlet and outlet should be checked to see if they are intact to prevent leakage. If any problems are found, they should be solved immediately; secondly, the water conditions for stocking should be observed, especially the escaped fish conditions in the pond should be understood to find out the details, so as to determine the stocking species and stocking quantity; finally, the water body should be improved. Due to the high temperature at present, the water body is generally turbid, there are many pollutants in the water, the water quality is very poor, and bacteria are easy to breed. Quicklime or alum should be used to spray water to clarify the water body and purify the water quality. If the water body is thin, a little fertilizer should be applied to cultivate natural bait in the water.

2. Stocking operation In order to reduce stocking mortality and ensure the stocking effect, the selection of supplementary fish species should be carried out. The selected fish species are required to have complete scales and fins, strong jumps, lively swimming, fat physique, and no diseases or injuries. Fish species with thin bodies, slow reactions, congestion on the surface of the body, and mechanical damage should be eliminated. The stocking species can be determined according to the source of the fish species and the stocking needs, but the stocking scale should be large, and the stocking density can be based on the principle of sparse stocking, so that the adult fish at the end of the year can reach the commercial specifications, reduce the adverse effects caused by the short growth period, and ensure the breeding benefits. When stocking, the fish species must be disinfected with drugs before being put into the water body to prevent the fish from entering the pond with diseases and causing the spread of fish diseases. Generally, 2% to 3% salt water or 1ppm to 2ppm crystal trichlorfon and other liquids can be used for immersion for 3 minutes to 5 minutes.

3. Management after stocking After stocking, the fish species should be carefully fed, fertilized, water quality regulated, and fish disease prevention should be done according to the species and quantity of the stocking. The feed is generally based on concentrated feed to accelerate the growth of the fish. The daily feeding amount is more suitable for 5% to 8% of the total weight of the pond fish, and the specific amount should be slightly left after feeding. If there are many fat fish such as bighead carp in the pond, more fertilizer can be applied. The principle of fertilization should be small amounts and multiple times. Organic fertilizer should be fully fermented before being applied to the water body, and the application amount per mu is 50 kg to 100 kg; chemical fertilizers can be used with ammonium carbonate (5 to 8 kg per mu) or urea (3 to 5 kg per mu) dissolved in water and sprayed throughout the pond to improve water quality. Within 7 to 10 days after stocking, spray strong chlorpyrifos (0.3ppm), bleaching powder (1ppm), etc. to kill bacteria; at the same time, you can spray a mixture of crystal dichlorvos (0.4ppm), copper sulfate (0.5ppm) and ferrous sulfate (0.2ppm) at intervals to kill parasites and effectively prevent the occurrence of fish diseases.