Slogan of doing well in aquaculture

Jiangsu has always been a treasure in the eyes of aquaculture. Here, whether it is the crucian carp in Yancheng, the river crab in Xinghua or the Macrobrachium rosenbergii in Gaoyou, it has a decisive position in the whole country. Although the breeding of Penaeus vannamei started late in Rudong, the rapid development of this species in the local area is enough to make Rudong the first county for Penaeus vannamei breeding in China. Taking the cultivation mode of Penaeus vannamei in Rudong greenhouse as an example, the cultivation mode and existing problems of Penaeus vannamei in greenhouse were introduced.

Advantages of cultivating Penaeus vannamei in greenhouse

1, small area, stable internal environment and strong controllability of the breeding process.

Because of the small pond area, shed culture is easy to enter and exit, and has strong wind resistance and is not easy to collapse. At the same time, compared with Longhai, Fujian and Pearl River Delta, the arc shed can keep heat better, so the internal environment is more stable, the water quality and bottom materials are easier to control, the controllability of the culture process is enhanced, and the survival rate of shrimp seedlings, sewage discharge and water exchange can be controlled. Management is more convenient and does not require too much manpower.

2. The temperature in the shed is stable and less affected by the external environment.

You can raise 2 ~ 3 shrimps a year, including spring shrimps from April to June and autumn shrimps from August to 65438+February. In the spring shrimp season, the temperature rises slowly, so the temperature difference will not be too big. Moreover, at the end of March and the beginning of April, under the condition of sunshine, the water temperature rises rapidly, which is 6 ~ 8℃ higher than that outside the shed and at least 10℃ higher than that outside the shed. When autumn shrimps are raised, the temperature difference between day and night is quite large, especially in shrimp ponds cultured by the sea, and the temperature difference between day and night can be as high as 10 degrees. However, when we build a shed, the shed film is like a protective layer, which is "isolated" from the external environment. Even if we breed at the seaside, the temperature difference is only 7 ~ 8℃ at most, which is much milder than open-air breeding. Even in the case of continuous rainy weather and cold air, the water temperature in the shed drops slowly, and it takes about 2 ~ 3 days to drop to 65438 0℃. Another point is that the arc shed can achieve the effect of heat preservation and temperature stability better than other sheds. Because the temperature is relatively stable and less affected by the outside world, the size of prawns is relatively uniform and tidy.

3. The enemy has less damage and is not easily infected by external diseases.

After the shed is built, the whole pond will be "completely closed" for breeding, and the good ones can't get out and the bad ones can't get in. This can not only effectively prevent and control the cross infection of viruses, germs and diseases and pests brought by the surrounding ponds, but also prevent and control the invasion and disease spread of harmful animals such as seabirds, snakes, rats, beetles, frogs, miscellaneous fish and shrimps. For example, mice themselves carry many harmful bacteria. If rats fall into the pond and rot, they will breed all kinds of viruses and diseases. But also avoids the inflow of polluted water sources, greatly enhances the safety of the culture process, and provides a very favorable environment and conditions for the safe growth of prawns.

4. Improve the utilization rate of ponds.

In Jiangsu province, at least two crops can be raised in a shed every year. The first crop can be sold in early July and the second batch of seedlings can be released in late July, so if conditions permit, three crops can be raised. In Jiangsu and Zhejiang provinces, if only open-air ponds are used for farming, they can only be farmed once a year. Therefore, it takes one year's pond rent and two to three years' money to breed in a shed.

5. Shorten the breeding cycle and seize the market opportunities.

Generally, it can be sold after 50 ~ 60 days in shed. If it is spring shrimp, that is, early seedlings leave the pond early, mainly fast, with a specification of about 60 heads, which is particularly easy to raise and has a larger specification. However, in open pond culture, it usually takes 70 to 80 days or more to produce shrimp. In this way, shed farming will be listed 20 ~ 30 days earlier than pond farming, so as to seize the market opportunity, and "things are rare", so it is not a problem to sell at a good price. On the contrary, if there are too many shrimps, the price will definitely drop and the income will drop accordingly. At the same time, shortening the breeding time of more than 20 days can also greatly reduce the costs of feed, electricity and labor.

Basic management of white shrimp culture in shed

1, water quality management

The conventional water quality standards in the process of Penaeus vannamei culture are: water temperature 22-32℃, pH 7.8-8.6, dissolved oxygen not less than 5mg/L, ammonia nitrogen; 100, total hardness "; 500, transparency 35-45cm, vibrio content.

(1) Fertilize and replenish fresh water in time according to the change of water color and biomass, and replenish water no more than 5cm every day.

(2) At the middle growth stage (6- 10cm), with the increase of water temperature and feeding amount, the organic matter in the water increased and phytoplankton flourished. Some zooplankton and protozoa that prawns can't eat will take the opportunity to flood and seriously consume dissolved oxygen in the pond. At this stage, important water quality indicators such as dissolved oxygen, pH value, ammonia nitrogen and hydrogen sulfide must be monitored twice a day.

(3) In the later period of culture (above 10cm), prawns are still in the rapid growth period, and water quality management is the most difficult. First of all, it is necessary to increase the water exchange capacity. The principle of changing water is a few times, and the amount of water changed each time should not be too large, so as not to destroy the stability of the pool water environment, cause stress reaction and cause shrimp disease, and the amount of water changed every day should be increased to about 20 cm; The second is to apply photosynthetic bacteria regularly (generally every 7 days 1 time, the whole pool is sprinkled, and the dosage is 0.5 bottles/mu).

Step 2 feed bait

(1) Use high-quality white shrimp feed and Longchang bile acid (protecting the hepatopancreas of prawns and promoting liver metastasis) in the whole process, feeding 4-6 meals a day in the early stage and 3-4 meals a day in the later stage.

(2) Each shed is equipped with two fishnets, and the feeding amount in the fishnets accounts for 65,438+0-2% of the total feeding amount, and the feeding amount is the best after eating for 65,438+0.5-2 hours, and the feeding amount is appropriately adjusted according to the feeding situation of prawns. If there are 50% leftovers in the current meal, there is no need to feed the next meal.

(3) In order to increase the transparency of prawns' body color and their ability to absorb feed, lactic acid bacteria 1 powder should be fed every 3-7 days, and the appropriate mixing ratio is 5-8‰.

3, timely disinfection:

Kill and eliminate harmful animals and plants in shrimp ponds in time. From the day before seedling release to the day before shrimp harvest, use Vibrio culture medium Vibrio/kloc-0 every 5-6 days, and decide whether disinfection is needed according to the test results. If necessary, use povidone iodine 200-250ml/mu of water for disinfection, and test again 5 hours after disinfection, and decide whether to continue disinfection according to the test results.