Breeding and feeding habit domestication of Pelteobagrus fulvidraco

1. Pond conditions: the area is 33.5 mu, the water depth is 1.2m to 1.8m, the silt 15~20cm, the water quality of the source is qualified. The pond is rectangular, east-west, with a length-width ratio of 5, 4, 3 and 2, which is convenient for entry and drainage.

2. Pond cleaning disinfection: quicklime or bleach powder is used to clean the pond, dry method is used to clean the pond, and 10~15cm is retained in the pond. 7 days before stocking, 150 kilograms of quicklime or 25 kilograms of bleach is used to disinfect the pond.

3. Fertilizing and cultivating natural bait: rotifer, nauplius, Cladocera, copepod and benthos are the feeding objects of Pelteobagrus fulvidraco fry from human pond to full-length 3cm.

Before entering the pond, the fish fry must apply sufficient basic fertilizer to cultivate the palatable natural bait, and the fish fry can catch the suitable natural bait in time and fully, which is helpful to improve the survival rate of fish fry.

Three to five days after clearing the pond, 500 kg of rotten chicken manure or 400 jin of cooked cow manure and 200 jin of green manure were applied per mu, and then 40~50cm was injected to cultivate red worms and rotifers, and filtered with 80-mesh silk cloth to prevent wild fish from entering. The fish fry were pulled out of the net once a day before going into the pond to remove frog eggs and tadpoles.

The fish fry must also be sprinkled with soybean milk in the whole pond 3 days before the fish fry goes into the pond. Each mu pond is soaked with 2 jin of dried soybeans every day and then ground into soybean milk and sprinkled in the whole pool.

4. Fish fry in the lower pond: generally, the size of purchased fish fry is relatively small. After buying back the fry, intensive cultivation should be carried out in a small cement pool or net cage for 2 to 3 days. After the specification reaches more than 1.2cm (preferably up to about 1.5cm), it is helpful to improve the survival rate by sending flowers in the soil pond.

5, fish fry under the pond method: yellow croaker fry under the pond should choose a sunny day at about 9 o'clock in the morning, because the temperature in the emergence stage of Pelteobagrus fulvidraco is higher, and the temperature at 9 o'clock in the morning is OK, the oxygen condition in the water gradually improves, at this time the fry is beneficial to the adaptation of the fry to the water temperature and other environment, and the vitality is also strong.

Seedlings must be scattered when the seedlings open, can not let it have the phenomenon of accumulation, otherwise it will cause a large number of deaths, thus affecting the survival rate of the whole flower.

6. Fry stocking density: the florescence stocking density of Pelteobagrus fulvidraco is smaller than that of other conventional fishes, usually about 8 ~ 100000 fry per mu of 1.5cm per mu; excessive density has a negative impact on the effect of flowering, and the difficulty of management will increase accordingly.

7. Precautions for fish fry restocking: slow fry treatment should be carried out in the operation of fish fry release-first, put the packing bag directly into the water. After 15-20 minutes, check the water temperature inside and outside the bag with a thermometer. When the temperature difference is within 0.5-1 ℃, pour the fry into the pond slowly.

8. Fish fry feeding: check the number of rotifers and red worms in the water 2 ~ 3 days after release. Every mu, 3 kilograms of soybean milk was used to cultivate rotifers and red worms twice a day in the morning and evening. If rotifers and red worms are not supplemented in time in the process of raising seedlings, the fish fry will soon dry up, spasm and die if they cannot eat the bait, which will directly affect the survival rate of breeding.

9. Domestication of feeding habits of fish fry: after 3-5 days of release, eel feed or juvenile soft-shelled turtle feed (crude egg content 42-46%) can be appropriately increased for fish fry consumption. If the number of rotifers and red worms in the pond is small, fertilizers should be properly applied and clear water should be injected to increase dissolved oxygen to promote the growth of rotifers and red worms.

Domestication steps: the fish fry can be domesticated after 3-5 days. First of all, about 10 feeding sites per mu of pond are selected for fixed-point feeding, and the balls are made of surimi, soft-shelled turtle and eel, and then cast on the feeding sites about 40cm above the water surface after 4 o'clock every afternoon.

One feeding site was reduced after 4 days, and then one feeding point was reduced every 3-4 days, until the remaining two feeding sites were finally set up, and the feeding table was changed from once a day to twice a day.

The table must reach the bottom of the water 40cm or so, which is conducive to the feeding of Pelteobagrus fulvidraco. Fish fry are finally domesticated to concentrate on artificial compound feed, which is convenient for checking the feeding condition of fish and preventing and treating diseases.

10. Water level management of fry rearing ponds: after releasing fry for 5-7 days, the water level of the pond was raised appropriately every 2-3 days, 8~10cm was added every time, and the water was gradually increased to 1-1.2 m.

11. Exercise and pond separation: after 20-25 days of feeding, the yellow croaker grows to about 2.5~3cm and should be sorted and reared. Before going out of the pond, the summer flower fry should be trained for 2 or 3 times. Make the fish species in the dense process, increase the adaptability of the fish body to hypoxia. Make the fish "sophisticated" strong, can withstand separate culture out of the pond, and avoid producing a large amount of mucus and feces to pollute the water quality in the process of transportation, and improve the survival rate of transportation. By pulling the net, you can also remove enemy organisms and estimate the number of summer flowers.

1), pull the net for the first time: gather the summer flowers in the purse seine and check their physique. Then put it back in the pool. The operation should be careful.

2), the second time to pull the net: every other day, carry on the second time to draw the net. After collecting the fish, let the top water enter the cage automatically. At this time, male and female fry can be screened by fish fry sieve, and put back into the pond after 2-3 hours.

3), the third time to pull the net: after the second time, the net can be pulled for the third time every other day, and the fish can be "suspended" for one night in the cage in the pool with cleaner water quality. at this time, male and female fish fry can also be screened by fish fry sieving, and long-distance shipment can be carried out in the early morning of the second day.

Exercise fish fry must choose fine weather, in the morning when the fish do not float head. The operation of pulling the net to drive the fish should be slow, so as not to hurt the fry. Don't let fish stick to the net when you close the net. After the fish is in the box. The box should be washed immediately to wash away the excrement and dirt of the sticky net, so that the water body inside the box and outside the box can be unblocked, so as to prevent the death of fish fry due to lack of oxygen in the box.

12. Methods of domesticating the feeding habits of yellow croaker fry:

A, reduce the total amount of animal feed in the water body: in the seedling stage, Pelteobagrus fulvidraco usually uses the methods of sprinkling soybean milk and applying biological fertilizer to cultivate animal feed. These operations must be stopped before domestication in order to reduce the total amount of animal food in the pond. For ponds rich in animal bait, necessary measures should be taken to kill bait animals.

Specific practice: in the leeward where zooplankton gather, sprinkle crystal trichlorfon on the area of the pond 1, 5, 1 and 3, so that the concentration of trichlorfon reaches 0.01~0.02ppm.

B, seize the opportunity and choose the appropriate specification: when the specification of cultivating Pelteobagrus fulvidraco in the pond reaches about 3 cm, the artificial bait with a certain particle size should be prepared according to the specification of Pelteobagrus fulvidraco.

C, running water to attract fish: flush with a water pump twice a day in the morning and evening one week before feeding, each time 2-3 hours. When flushing, the outlet should keep level with the surface of the pond as far as possible, and the amount of water output depends on the area of the pond. Pelteobagrus fulvidraco has the habit of top water, and the main function of flushing is to gather Pelteobagrus fulvidraco together for easy domestication. Pelteobagrus fulvidraco generally clustered at the edge of the pond at the seedling stage, and the pump mouth should be close to the edge of the pond as far as possible to achieve the best effect of gathering fish.

D, food farm and bait machine installation: set up a round or square food farm in the place where the fish shoal is concentrated at the pump mouth. Four bamboo poles with a diameter of 3~4cm (each with a length of 3mm and 4m) were connected into a square fence, which was placed in the pool, the position coincided with the feeding area of the bait machine, and then fixed with anchors or piles. The food farm can also be made of pvc tube or 40-mesh mesh cut into narrow bands.

E. Hunger feeding: after two to three hours of flushing, begin to manually sprinkle an appropriate amount of artificial feed into the food farm, and turn off the water pump before feeding. The feed size should not be too large, usually below 1mm. In the case of no palatable particle size, the feed of large size can also be soaked in appropriate amount of water and crushed.

F, feeding time: after sunset on a sunny day and before sunrise in the morning, feed twice a day for about 30 minutes. The amount of feed depends on the size of the fish, and the feed must be put into the food farm. Generally after 3-5 days of domestication, Pelteobagrus fulvidraco can be seen feeding in the semi-water layer, 6-8 days later, Pelteobagrus fulvidraco can graze on the water surface, at this time can be used to feed on the bait machine.

G. Enter the normal feeding stage after domestication: twice a day, before 8:00 in the morning and after 5:00 in the afternoon. According to the feeding condition of fish fry and the weather, the daily feeding amount is 60.8% of the total weight of fish.

13. Daily management of yellow croaker fry cultivation pond: patrol the pond once every morning and evening to fish out dirt, frog eggs and so on. Observe the water color and the activity of fish, arrange the amount of bait and water injection, disease prevention work and so on. Pay attention to the weather, water temperature, water color, eating and other conditions, and make detailed records.

14. Water quality regulation of yellow croaker fry culture pond: before entering the pond, the water depth should be controlled at about 50~60cm, and the water quality should be fat and cool. After entering the pond, according to the water color and weather, flush once every 2-3 days, each time 8~10cm, and the water depth should be controlled at 1-1.2m in the later stage.

Start the aerator from 12:00 to 14:00 on a sunny day to increase oxygen for two hours and stir the pool water to increase dissolved oxygen. Sprinkle with 15ppm quicklime every half a month to keep the pH between 7 and 8. In the whole culture process, water was injected for 5 times and 7 times, and 8~10cm was injected each time. Take the bait every half month for three days, and feed with 0.1% tetracycline or oxytetracycline to prevent the occurrence of fish disease.

15. Fishing of Pelteobagrus fulvidraco fry: because Pelteobagrus fulvidraco is a benthic fish and has a mild temperament, the catching rate of pulling net is higher. More than 80% of the fry of yellow croaker in the pond can be pulled up by pulling the net with suitable mesh size and pulling back 2 times in the breeding pond.

16. Points for attention in the process of summer flower cultivation of Pelteobagrus fulvidraco:

A. The body length of Pelteobagrus fulvidraco seedlings is only 3~5mm, the yolk sac is large, and the activity ability is weak. They like to cluster at the bottom of the water body and get nutrition by absorbing yolk. As the individual grows up, the yolk sac gradually shrinks, and the free swimming ability is gradually improved. However, its adaptability to the ecological environment is poor, and it can only ingest food in dark and low light conditions. It should first choose no mud, no pollution and fresh water quality. Cultured in a pool with high dissolved oxygen.

B. Before 2cm, yellow croaker fry mainly fed on rotifer, red worm, Cladocera, Chironomus larva and so on, which was similar to Siduan fish, and then gradually changed to omnivorous. However, if we adopt the same breeding method as the four major domestic fish, the survival rate of fish fry will be affected. Therefore, it is the key to improve the survival rate of seedlings to cultivate rotifer and other biological bait before the spray goes into the pond.

C. Pelteobagrus fulvidraco likes to live in fresh, alkaline and sufficient dissolved oxygen water, so quicklime should be often used to regulate the water quality, new water should be injected, and aerator should be used to increase oxygen, so that the pH value of the water body is between 7 and 8, and the dissolved oxygen content is above 6mg/L.

D. Taking bait every half a month in the process of cultivation can effectively prevent the occurrence of diseases.

E, Pelteobagrus fulvidraco summer flower pond culture, to ensure that the same batch of fish fry under the pond, a sufficient quantity.

F. The fry of Pelteobagrus fulvidraco during the period of feeding and domestication must not be dragged and refined so as to avoid failure of domestication.

17. Special precautions: Pelteobagrus fulvidraco is a scaleless fish, and its tolerance to commonly used aquatic drugs is not as good as that of the four domestic fish. The 24-hour and half-lethal concentrations of several commonly used drugs are: copper sulfate 0.69 mg / L, 90% crystal trichlorfon 2.8 mg / L, salt 25 g / L, formalin 68 mg / 1.

When giving drugs to Pelteobagrus fulvidraco, the dosage must be strictly controlled to avoid drug poisoning. Pelteobagrus fulvidraco is sensitive to malachite green, copper sulfate, mercurous nitrate, potassium permanganate and trichlorfon.

18. Fish fry and fry transportation: in the process of transporting fish fry and fry, no matter what method is used, the operation must be meticulous. Pay attention to the following aspects:

1), the fish fry are physically strong, swimming is lively, and the amount of oxygen-filled transport in nylon bags is about 80% of the transport box.

2) the water quality is fresh and non-toxic and the dissolved oxygen content is high. The water of rivers, lakes, reservoirs and ponds can be used, and the water with colorless transparency and low mud content should be selected. Tap water should be dechlorinated and stored for 24 hours before use. Use cold water in summer.

3) before the fingerling is transported, the fish should be trained by pulling the net to remove feces. The body is strong, reduce mucus secretion, in order to improve the survival rate.

4) pay attention to the temperature balance, the temperature difference should not be ±2 ℃, after arriving at the destination, you should first wake up the fish in the box, and feed the fish fry with cooked egg yolk an hour later. 100000 fish fry are fed with one egg yolk. After seeing the fish fry sausage (swallowing the egg yolk into the intestine), wait another hour before putting the fish into the pond. For the fish fry in nylon bags and transport boxes, put them into the water before leaving the box to make the internal and external water temperature consistent. Then open the nylon bag or transport box, pour water into the pond, put the bag into the box, and let the fry (fry) swim out on their own.