What are the key points of production and management of sea cucumber pond culture? The Ministry of Rural Agriculture gives the latest guidelines!

Department of Agriculture and Rural areas of Hebei, Liaoning, Jiangsu, Zhejiang, Fujian, Shandong, Guangdong and Hainan provinces, Marine and Fisheries Bureau of Fujian Province, Agricultural and Rural Bureau of Dalian, Qingdao and Ningbo, Qingdao Marine Development Bureau:

In order to further promote the green and high-quality development of sea cucumber aquaculture and strengthen the supervision of the quality and safety of sea cucumbers, our bureau, together with the National Aquatic Technology Promotion Station, organized experts in the fields of healthy sea cucumber culture, disease prevention and control, and formulated the "guidelines for the production and Management of Sea Cucumber Pond Culture", which is now issued.

Please organize the administrative, law enforcement, promotion and scientific research units within your jurisdiction, combine the current special rectification action on illegal and illegal use of drugs in sea cucumber farming and standardize the activities of popular science in drug use to the countryside, and use all kinds of media to carry out publicity and training. create a good social atmosphere to ensure the quality and safety of cultured sea cucumbers.

Fishery and Fisheries Administration of the Ministry of Agriculture and villages

August 2, 2020

I. Daily aquaculture management

(1) clear the pond

After the completion of the new pond and before the release of seedlings, it is necessary to clear the pond. The old pond is usually cleared once every 2-3 years. Drain the stagnant water from the ponds and ditches, wash and remove the dirt and sundries at the bottom repeatedly, dig out too much silt, then close the gate and dry the pond for more than a week, turn over the unoxidized bottom mud to the surface and continue to oxidize, so that the organic matter can be decomposed completely. After basking in the pond, the pond is thoroughly disinfected to kill crabs, wild fish and other enemy organisms, and to prevent the growth of a large number of algae. Disinfection requires the use of quicklime and sodium hypochlorite solution (aquaculture), chlorinated lime (aquaculture) and other aquaculture veterinary drugs approved by the country, sprinkle the whole pool of water according to the usage of the product manual, drain the water after soaking for 10 days, and then introduce seawater to soak for 3 days, drain the water, and repeatedly enter and drain it for 1 or 2 times. It is strictly forbidden to use dichlorvos and other pesticides, APIs and other toxic and harmful substances for disinfection.

(2) basic bait culture

According to the fat and thin water quality in the culture sea area, sea cucumber seedlings can be put into sea water 10 days in advance to facilitate the reproduction of benthic diatoms and other unicellular algae and provide sufficient basic bait for sea cucumber seedlings. The pond water was fertilized with a compound fertilizer with a nitrogen-phosphorus ratio of 5 to 5 per hectare (75kg / ha). It can be adjusted according to the water color to keep the transparency of the pool water around 50cm, and the content of nitrate in the water is lower than 10mg/L. Chemical or biological fertilizers that are not registered by the State shall not be used.

(3) Seedling release

1. Seedling selection

Seedlings should be purchased from the original improved aquatic seed farms or seedling production units at or above the provincial level with the "Aquatic Seedling production license". The seedlings purchased must have the quarantine certificate of the origin of the seedlings. When choosing and purchasing, we should pay attention to the neat specifications of the same batch of seedlings, with more than 2cm in body length, strong vitality and adhesion, sensitive response to stimulation and strong contraction.

two。 Time to put in seedlings

The water temperature of the pond is above 10 ℃ from April to May in spring, and when the water temperature of the pond is below 22 ℃ from October to November in autumn. It is appropriate to plant seedlings in the morning or evening, and do not let go, that is, "do not let go on rainy days, windy days, hot weather, too strong sunshine".

3. Seedling specification and density

The suitable seedling specification of sea cucumbers in spring is 300 heads / kg, and the seedling density is about 45000 / ha. In autumn, it is suitable to release seedlings with 100 heads per kilogram, and the seedling density should be controlled at about 45000 per hectare. The seedling density should be adjusted reasonably according to the pond conditions and the size of ginseng seedlings.

4. Seedling method

Before putting in a large number of sea cucumber seedlings, a small amount of sea cucumber seedlings can be put into the experiment, observed for about 7 days, and then put in large quantities after seeing no abnormal activities, feeding and so on. When throwing seedlings, it should be noted that the water temperature difference between the purchased seedling land and the pond should not exceed 2 ℃, and the salinity difference should not exceed 5 ‰. The sea cucumber seedlings were evenly sprinkled in the waters where the reefs were located when the seedlings were put in. The distribution, activity, feeding and survival of sea cucumber seedlings were observed within 3 days.

(4) Water quality control

The water color, water temperature, water level, salinity, pH value, dissolved oxygen in the bottom and algae growth in the pond were observed on time, and the feeding activities and stool types of sea cucumbers were carefully observed. Change the water in time according to the tide cycle and water quality. The low salinity water on the surface should be discharged in time after heavy rain, and avoid changing water or changing water less when there is a big difference in water temperature inside and outside the pond. The water level should be maintained at 1m-1.5m in spring and autumn, and the water level should be kept above 1.8m during summer and hibernation. The requirements of the main physical and chemical indexes of water quality are as follows:

1. Dissolved oxygen: it is required to reach more than 3.5mg/L, when the 2.0mg/L is below, the young ginseng body does not stretch, the adhesion is weakened, easy to sink the bottom of the pool, lower than 1mg/L, it is easy to cause sea cucumber death.

two。 Salinity: the suitable growth salinity of sea cucumber is 28-32 ‰. If it is in the state of low salt and high salt for a long time (less than 22 ‰ and more than 38 ‰), it will lead to slow growth, decrease of stress resistance and disease.

The growth between 3.pH:7.8-8.5 is better, when it is less than 7.2or more than 9, the vitality of young ginseng weakens, the growth stops, and it is easy to cause death.

4. Ammonia nitrogen: the semi-lethal concentration is 1.65mg/L, the higher the pH value, the greater the proportion of undissociated ammonia. Nonionic ammonia can inhibit the normal growth and development of sea cucumber seedlings and reduce the resistance to disease.

5. Hydrogen sulfide: the decomposition of sediment, residual bait, corpses, feces and organic matter is the main source of hydrogen sulfide, and the safe concentration is below 0.002mg/L.

(5) Feed feeding

Sea cucumbers grow fastest when the water temperature is 10 ℃-20 ℃ in spring and autumn, and can be fed manually when the basic feed is insufficient. The feeding amount can be adjusted according to the intake and growth of sea cucumbers. Generally, the body weight of sea cucumbers is about 0.5% each time, once every 7 ℃ every 10 days, and stop feeding during summer hibernation when the water temperature is higher than 20 ℃ and during hibernation when the water temperature is lower than 5 ℃. Strictly abide by the regulations on the Administration of Feed and Feed Additives, artificial bait is made of sargassum powder, sargassum powder, kelp meal, fish meal and other raw materials in a certain proportion, or commercial sea cucumber special artificial compound feed is used. generally, the crude protein is within the range of 18%, and the fat is no more than 5%. The hygienic standard of sea cucumber feed should conform to the "Feed Hygiene Standard" (GB13078-2017), and the quality standard should conform to the "Sea Cucumber compound Feed" (SC/T2037-2006) and other relevant provisions.

(6) Disease control

1. Preventive measures: prevent too much bait, keep the pool bottom and water quality clean, and prevent diseases such as skin rot syndrome. Appropriately increase the water depth, reduce the transparency of the pond water, prevent the breeding of macroalgae, remove the macroalgae in the pond in time, and prevent the deterioration of the bottom environment caused by the death and decay of algae. In summer, high temperature disasters can be prevented by increasing pond water depth, reducing pond transparency, laying sunshade net, using pond cooling equipment and so on. The use of ground cages or the use of light at night to trap crabs and other enemy organisms to reduce the enemy biomass in the culture pond.

two。 Treatment measures: veterinary drugs approved by the state for aquaculture should be used in strict accordance with the instructions, and the use of fake or inferior animal drugs and drugs and other compounds prohibited by the state shall be prohibited. Strictly implement the system of drug withdrawal period.

(7) Prevention and control of biological enemies

In the process of culture, the pond should be cleared regularly, the timing of water intake should be controlled, and a barbed wire mesh with an aperture of 1cm-2cm should be set up at the inlet to filter weeds and sundries. Under the condition that the filtration is not affected, a polyethylene net of 2m, 3m, 30m, 50m should be added to intercept and filter macroalgae, fish, shrimp, crabs and other enemy organisms.

1. Enteromorpha and other macroalgae: in early spring, it is necessary to control the algal bacterial phase and keep the transparency of the pond water around 30cm, which can effectively prevent a large number of macroalgae such as yellow cabbage from growing. If there are large algae in the pond, manual fishing can be used in time, and it is strictly forbidden to use herbicides (algae) and other pesticides.

two。 Biological enemies such as fish, shrimp and crabs: shrimp and crabs can be trapped with ground cage nets, carnivorous fish can be killed with sticky nets or hooks, and starfish are found to be picked up and dried outside the pond.

II. Other technical points

(1) points for attention in aquaculture in flood season

The aquaculture pond is equipped with a fresh water discharge valve (gate) to quickly drain the fresh water layer at the top of the pond during concentrated rainfall in the flood season. After the flood season, the rotten algae is thoroughly removed, and the dissolved oxygen in the culture pond water is closely monitored. When it is lower than 3mg/L, the mechanical oxygen enrichment method can be adopted to increase oxygen.

(2) matters needing attention in summer culture

During the high temperature period, the depth of the pool should be increased to more than 1.8 meters to avoid sudden changes in water temperature with the air temperature. The pond with an area of less than 4 hectares can be covered with a sunshade net during the high temperature period, and the sunshade net is more than 1.5 m from the surface of the pond. The low temperature water pipe can also be used to reduce the temperature, and at the same time, it can increase the dissolved oxygen in the pool water, which can effectively reduce the water temperature 1 ℃ 2 min. In order to prevent death from high temperature in summer, the sea cucumbers in the pond can be transferred to the summer workshop and transferred back when the pond water temperature is suitable.

(3) matters needing attention in winter culture

The depth of pool water should be increased to more than 1.8 meters in winter, stomata should be opened in time after freezing, snow on ice should be removed in time, pool water transparency should be increased, photosynthesis of phytoplankton in water should be enhanced, and dissolved oxygen should be monitored regularly. to ensure that sea cucumbers will not die due to hypoxia or oxygen supersaturation caused by sea cucumber diseases. Patrol the pond in time to prevent the pond gate from leaking.

The above guidelines are for reference. Sea cucumber culture and production should strictly abide by the relevant laws, regulations and standards.