1, pond conditions. It is required that the water source is sufficient, there is no pollution source, and the water quality meets NY505 1 standard. The shape of the pond is relatively regular, the suitable area of a single pond is 2.5 ~10 mu, the water depth is1.2 ~1.5m, the slope ratio is1:2.5, and the silt depth at the bottom of the pond is less than 15cm. One end of the pond is provided with a water inlet and the other end is provided with a water outlet.
2. Supporting facilities. The water inlet and outlet are made into mesh bags with 60 ~120 mesh for double-layer filtration to prevent wild fish from being brought in. The pond is equipped with a water pump 1 set, and each acre of pond is equipped with a waterwheel aerator with a power of 0.5 ~1.0kw. It is best to equip every 20 acres of pond with 1.5kw bottom micropore aeration facilities. Equipped with ground cages and nets to catch seedlings, and built a watch room and feed warehouse.
3. Clean the pond. Renovate the pond in winter to ensure that the bottom is flat and there are no pits and ditches, and remove excessive silt. At the same time, heighten, reinforce and tamp the pond ridge to prevent the pond from leaking. For old ponds that have been cultivated for many years, it is necessary to use fine weather to drain the accumulated water and dry the pond bottom for more than 10 days, so as to achieve complete whitening and dry cracking, and the drier the better.
4, disinfection and water injection. Add water 10cm or so, and use 50 ~100 kg of quicklime per mu. After hydration, sprinkle it in the whole pool while it is hot, and stir the lime blocks at the bottom evenly with an iron rake the next day. 5 ~ 7.5 kg bleaching powder containing 30% available chlorine can also be sprinkled to kill harmful organisms such as wild fish in the pond. Before the parent shrimps are stocked 1 week, fresh water is filtered and injected to make the water depth of the pond reach about 60cm.
5. Fertilize and plant grass. After water injection, 50kg of fermented chicken manure can be released per mu, and 200ml of amino acid fertilizer water essence and photosynthetic bacteria 1.5kg fertilizer water can be sprinkled per mu. And transplanted Elodea nuttallii, Alternanthera philoxeroides and other aquatic plants to the pond with a coverage rate of about 20%. In order to facilitate the operation of pulling nets, some artificial shrimp nests made of multi-branched trees such as tea trees and willow trees can also be set up.
Second, the introduction and stocking of parents
1, parental introduction. Parents must introduce F0 or F 1 generation shrimp or shrimp fry from the original seed farm above the provincial level, and the time is from 1 month to the end of March. The introduction time should be sooner rather than later. Too late, due to the rising water temperature, green shrimps will enter the peak of molting, and a large number of soft-shelled shrimps will appear, which will affect the survival rate of transportation.
2. Means of transport. Parents are transported by oxygen-increasing net partition method in water tank. The water tank can be made of tin sheet or glass fiber reinforced plastic. The iron mesh frame [100×50× 15(cm)] is sealed with a dense mesh with a mesh of 0.4 ~ 0.6 cm, which is buckled with a mesh cover. After the shrimps are put into the water tank, the water level in the tank should be 5 ~ higher than the top mesh. At the bottom of the water tank, there is an aeration device. Oxygen is increased by an oxygen cylinder or an air pump, and bubbles and water flow upward from the middle of the bottom mesh partition, so that there is enough dissolved oxygen in each mesh partition.
3. Transportation method. The quantity of shrimp loaded depends on the transportation time, generally, the interval between nets should not exceed 10kg, and the transportation time on the way should not exceed 6 hours. Parents should be careful in transportation operation, try to avoid parents being injured, make full preparations before transportation, pay attention to connection, and try to shorten transportation time.
4. Cultivation methods. First, the introduced parents are put into a special parent cultivation pool, and after they are raised in May, the parents are caught out in a cage, and they are sparse in a seedling cultivation pool according to a certain male-female ratio and quantity, and then shrimp seedlings are bred. Second, the introduced parents are directly put into the nursery pond, and the seedlings are raised in the original pond after May, and there is no need to separate the ponds. Production practice has proved that the second method is simple, easy to operate, with little damage to parents and relatively good seedling effect.
5. Parental stocking. The specification is about 1000 fish /kg, with 5 ~ 6 kg per mu. Choose sunny and warm weather for stocking, and avoid freezing and windy weather. When parents stock, they should pay attention to the temperature difference between the transportation water temperature and the pond water temperature not exceeding 5℃. If the temperature difference is too large, they must adjust the water temperature moderately before putting it into the pond.
Third, parental cultivation and management
1, bait feeding. The feed should be fresh, palatable, free from spoilage and pollution, and the crude protein of granular compound feed should be above 35%. The feeding amount should be flexibly controlled according to different months, water temperature, weather, water quality and food intake. When the water temperature reaches above 8℃ after stocking, parents can choose to feed bait on sunny mornings, usually once every 2 ~ 3 days, and the feeding amount is1%~ 3% of the shrimp weight. Enter the normal growth stage, and feed twice a day at 8-9 am and 5-7 pm, respectively. Feed 1/3 of the daily feed in the morning and 2/3 of the daily feed in the afternoon. The feeding amount is usually 2%-8% of the total weight of shrimp in the whole pond. In the early stage, it should be fed evenly in the shallows around the pond, which are about1~ 2.5m away from the edge of the pond. In the middle and late stage of culture, it should be spread all over the pond, and in the early stage, it should also be spread all over the pond with shallow water or more aquatic plants over 5 mu.
2. Water quality control. The transparency of pond water for shrimp breeding should be controlled at 30 ~ 45 cm, the dissolved oxygen should be kept above 5mg/L, and the pH should be 7.0 ~ 8.5. The water depth should be kept at 0.6～0.7m before mid-May, and at 0.8 ~1.0m from mid-May to the end of June. During the breeding period, depending on the fat and thin water quality, topdressing or fresh water should be added in time. If the water is too clear, decomposed organic fertilizer can be applied; If the water is too strong, new water can be properly injected to dilute the concentration of water. Every10 ~15 days, beneficial microecological agents such as EM bacteria and Bacillus subtilis should be applied to improve the water environment, and the water quality of shrimp ponds should always meet the requirements of fat, liveliness, tenderness and freshness.
3. Water grass control. When parents are cultivated in special ponds, the coverage rate of aquatic plants should be controlled at 25% ~ 50% during the cultivation period, and they should be evenly distributed in the pond in clusters. Parents should be cultivated directly in the nursery pond without aquatic plants, but some artificial shrimp nests should be placed.
4. Daily management. Patrol the pond once every morning and evening to observe the change of water color, shrimp activity, molting number and food intake; Check the shrimp pond for leakage and whether the escape prevention facilities are in good condition. Take corresponding measures in time when problems are found. Pay attention to the dissolved oxygen situation in the pond every day. When patrolling the pond, it is best to use an oxygen detector to detect the dissolved oxygen at the bottom, turn on the aerator at the right time or take measures such as flushing to improve the dissolved oxygen in the pond and prevent the shrimp from floating and flooding the pond. Make a record of the tangkou every day, including weather, air temperature, water temperature, water quality, feeding and medication, food intake and so on.
Four, shrimp breeding and cultivation
1, check the egg-bearing shrimp. Generally, in early July, most female shrimps have held their eggs, and their eggs have changed from dark green or taupe to transparent or grayish white, and the embryos have black eye spots. At this time, fertilization will be started to cultivate the food organisms that shrimp larvae like rotifers, cladocera, etc., and chicken manure 100kg can be fully fermented and decomposed per mu, and the fertilizer will be put in waste feed bags and fixed by ropes to float in the water, so as to gradually release the fertilizer effect, and 0.5kg of microecological preparation will be applied to the pond per mu to adjust the water quality.
2. Early cultivation of shrimp seedlings. When flea larvae appear in the nursery pond, sprinkle soybean milk in time. The amount of soybean milk is adjusted according to the water fertility and weather conditions, generally, it is1~ 4 kg per mu per day. When the pond water is fat and plankton increases, the amount of soybean milk should be reduced appropriately. When the pond water is thin and plankton is less, the amount of soybean milk should be increased. The daily amount depends on the water quality.
3. Feeding young shrimps in the middle and late stage. Generally, the larvae begin to metamorphose about 20 days after hatching. At this time, while splashing soybean milk, they are fed with powdered compound feed. With the increase of the proportion of metamorphosed seedlings, the proportion of powdered compound feed is gradually increased, and finally all of them are fed with powdered compound feed, and the daily feeding amount is 6% ~ 8% of the shrimp weight.
4. Water quality control of nursery pond. The depth of the pool water is generally controlled at about 1m, and water is usually added once every 3 ~ 5 days, with 5cm each time. During shrimp seedling cultivation, compound Bacillus is used once a week, the dosage is per mu 100g, and the bottom modification is used once every 10 day, which is beneficial to the decomposition of organic matter at the bottom of the pond and the adsorption of toxic and harmful gases. Start the aerator every morning to increase oxygen until sunrise, and keep the dissolved oxygen above 5 mg/L.
Five, shrimp fishing and transportation
1, shrimp fry fishing. The catching period usually ends in the middle and late July and mid-August. After hatching, after 35 ~ 45 days' cultivation, the total length of the young shrimp is more than 1.2cm, which shows that a large number of young shrimp swim by the water, and the young shrimp can be caught. The damage of shrimp seedlings caught by pulling net method is light. Before catching seedlings, we should make full preparations and join up, and the operators should be quite skilled and move quickly.
2, shrimp transportation. The grid box of running water vehicle is filled with pure oxygen in layers for transportation. Shrimp larvae are caught and transported in the hot season, so it is not suitable for long-distance transportation. The transportation time should be controlled within 1 hour, and pond water should be used for transportation, so as to reduce the stress reaction caused by excessive temperature difference. Before transportation, check the transportation tools and various preparations, pay close attention to the water temperature and oxygen increase during transportation, and do it quickly, quickly and quickly, and do not delay the time artificially.