Measurement items Adaptation bad PH 8～9 7.5 or below 9.5 Dissolved oxygen (7~10)10-6 310-6 or less or 1210-6 salinity 0.015 to 0.025 0.010 or less or 0.035 or more Non-ionic ammonia (NH3-N) (0.1-0.5)10-6 0.610-6 or more Phosphate (PO4-P) (0.2 to 0.4) 10-6 0.610-6 or more Hydrogen sulfide (0~0.2)10-6 0.610-6 or more Nitrite (0.01-0.05)10-6 Above 0.0610-6 Frozen Squid Rings,Fresh Frozen Squid,Frozen Whole Squid,Frozen Cooked Squid Zhejiang Zhoufu Food Co., Ltd. , https://www.zhoufu-food.com Grass shrimp, scientific name platycodon prawns, also known as black shell shrimp, belongs to the shrimp family. Because this shrimp likes to inhabit aquatic plants, it is called grass shrimp. Grass shrimp has the characteristics of rapid growth, miscellaneous food, wide salinity, short breeding cycle, large individuals, delicious meat, rich nutrition, and high yield of shrimp. Therefore, the shrimp has become an important target of current farming. Now its healthy breeding technology is introduced as follows:
Shrimp pond
1.1 The pool shall be constructed in areas with flat terrain, less silt, adequate water sources, good water quality, no pollution, and convenient drainage and drainage. It is appropriate to use an area of ​​5 to 8 mu of sandy bottom with a water depth of 2m. Each pond is equipped with 2 to 3 2.2kW aerators. Old ponds should be cleared of sludge and weeds in the pond or plowed to expose the bottom of the pond.
1.2 Disinfecting ponds in clear ponds Intake water 15 to 20cm in the pond before putting on seedlings for 20 days, and use Quantang agent Quanchiposa to kill the hostile microorganisms. Some newly-excavated ponds and aging ponds with poor exchange capacity of some water bodies should be used in advance in order to prevent the occurrence of harmful algal blooms in the middle and late breeding period. Algae-killing agents, such as algae-killing and grass-catching nets, should be used to kill the pool. The bottom of harmful algae.
1.3 Purification of incoming water, adjustment of the salinity shrimp ponds After the disinfection and disinfection of the shrimp ponds, water is supplied. When receiving water, it must be filtered through a 60-80 mesh screen to prevent the entry of harmful organisms. After entering the water for 80-100 cm, the water body shall be disinfected, and the virus shall be killed by using powerful mycorrhizal drugs and other drugs. At the same time, the drug was disinfected with a sprayer and the drug concentration was appropriately increased. The salinity of the pond should be consistent with the desalination of the shrimp seedlings in the nursery room.
1.4 The use of shrimp Terry has a comprehensive effect. Once the shrimp Terry is put into the pond, diatoms are cultivated in 2 to 3 days. After the basic biological feed is cultivated, the water quality meets the following requirements and then the seedlings are released.
1.4.1 The color of visually measured pool water has turned yellow-brown or dark brown, yellow-green, and the transparency is about 25cm.
1.4.2 Instrumentation Use a microscope to observe the density of microorganisms, and use the water quality analysis box to test the water quality indicators and place the seedlings after meeting the requirements.
1.5 The aerator type impeller aerator has the best effect and is set in the deep water in the pool. Within one month after the seedlings are released, they are turned on one at a time each day at noon and before dawn, and each time they are turned on for 2 to 3 hours. One month later, it is switched on at noon and before dawn every day. It is switched on for 3 hours at noon and it is turned on for about 10 hours before dawn. Rainy days increase boot time and frequency. In the latter part of the breeding period, it should be turned on for no less than 20 hours throughout the day.
2. Shrimp
2.1 Selection of shrimp
2.1.1 Principles for purchasing grass shrimp seedlings 1 Purchasing high-healthy shrimp seedlings (HHS) or prawn disease detection centers are monitored as virus-free shrimp seedlings.
2 without high temperature seedlings and misuse of antibiotics.
2.1.2 Individual shrimp should be uniform. The same batch of shrimp should have a body length of 1.0 to 1.2 cm. The body surface should be clean and vigorous, and the slender section of the abdomen should be a good seedling.
2.1.3 The two small tentacles on the front of the healthy shrimp are close together. Occasionally, they are separated, but they can be closed immediately. Those who cannot be closed are poor shrimps. The tail fan of healthy shrimp is open.
2.1.4 Healthy shrimp have "sticky wall behavior". If a shrimp is picked up with a spoon, the strong shrimp will quickly swim to the side of the spoon and stay close to the wall of the spoon. If swimming in the water, it is unhealthy shrimp.
2.1.5 Take several tails, about 1cm in length, from the nursery pond, and immerse them in a wet towel for 5 minutes. Remove them and return them to the raw water. This will have no effect on the survival rate.
2.2 Stocking of shrimp
2.2.1 Before watering, the water body must be disinfected to ensure that the water environment of the shrimp nursery and the water environment of the culture pond are within safe limits. In addition, pay attention to the water test before stocking, after 1 to 2 days of test water, the pond water environment has no effect on the survival rate of shrimp seedlings can be put in batches.
2.2.2 Matters needing attention:
1 Fangmiao should choose the side of the shrimp pond sheltered from the wind, should not be placed in the wind or seedlings in shallow water.
2 The weather is not good, but not seedlings. You should choose to release the seedlings at 8 to 9 o'clock in the sunny morning or in the afternoon when the sun sets, and do not put seedlings at noon.
3 Do not rush to plant seedlings if the damage is not complete.
4 shrimp pond water color is not good and water quality is not good to put seedlings.
2.3 The stocking density of stocking density should be between 8,000 and 12,000 tails/mu. Because of the different pond conditions, the amount of seedlings can be increased or decreased according to the actual situation.
3. Cultivation management "Shrimp cultivation is water" has become the experience of the majority of shrimp farmers. Maintain good water quality to facilitate shrimp feeding and promote growth of shrimp skin.
3.1 Water quality The optimum range of water quality for grass and shrimp ponds is shown in the table below
3.2 The following principle should be followed when changing the water and changing the water volume:
1 Change less during the day and more at night.
2 days and less change, Tianyin change.
3 less wind change, no wind more change.
4 big pool change, small pool change.
5 Density change, density mostly change.
6 If the biomass is too high, replace it with less.
7 The water is too thick and less than 20cm in transparency.
8 The water temperature is less than 20°C, and the water temperature is higher than 32°C.
9 When the water odor has to be completely replaced and it cannot be replaced, it is necessary to use the "clean water essence" and the "fish and shrimp pool bottom cleaning agent" for comprehensive treatment.
When you add water for 10, you have to drain first. Use well water ponds and pay attention to the poisons of adsorbed chromium heavy metals.
3.3 Cultivation and Management of Aquaculture
3.3.1 Water color The so-called water color refers to the color of the pool water in the sunlight. Aquaculture water can be summarized as follows:
1 Red-brown water: The main contain diatoms. It is the best color for shrimp farming.
2 light green, emerald green water: the main green algae. Chlorella can absorb large amounts of nitrogen fertilizer in water and purify the water when it is multiplying. Therefore, shrimp grows fast in green water bodies. This water color is also the desired color of the culture.
3 dark green water: the main contains blue-green algae. Aging pools are prone to occur. In this type of water, shrimp can survive, but the disease rate is high.
4 dark brown and soy sauce water contains flagellates and so on. Improper feeding and deterioration of the aging pool are prone to aging. Some dinoflagellates secrete paralytic neurotoxins that kill shrimp poisoning. This kind of water color is an abnormality in management. The main reason is that the poor quality feed is fed too much, the amount of residual bait is increased, resulting in increased solubility and suspended organic matter, and brown algae multiply.
5 yellow water: The main contains gold dinoflagellates. This water color is not suitable for the cultivation of shrimp fish, but it is suitable for the growth of shellfish. Change water immediately to increase dissolved oxygen, at least make the water yellow and greenish.
6 white turbid water: The main contains ciliates and other zooplankton and clay particles or organic debris. This kind of water color, shrimp is easy to get sick, pay attention to the conversion of water color.
7 Yellowish-yellow white water: It is caused by the fine clay on the embankment caused by rainwater entering the pool. It is not suitable for raising shrimp.
8 Clarifying color water: Due to lack of nutrient salts or pollution by heavy metals without phytoplankton, it is not conducive to shrimp aquaculture.
3.3.2 measures to change the water color 1 increase the displacement, add water treatment has been disinfected.
2 Use Terry shrimp or seawater auxin to forcibly breed beneficial algae and change the color of the water.
3 Shrimp poisoning or algae killing algae disinfection, until after the efficacy period of fertilizer and water.
4 Use probiotics as a "fish and savior" to improve the bottom of the pool.
3.4 Feeding
3.4.1 Feeding amount According to the physiological needs of each growth stage of prawns and the living conditions at that time, accurate and reasonable feeding was conducted. The daily feed amount (complex feed) of grass shrimp is generally calculated according to the weight of each tail. 1g body weight, feeding amount is 16% of body weight, 2g body weight is 14%, 3g body weight is 12%, 5g body weight is 10%, 8g body weight is 8%, 15 to 20g body weight is 6% to 5%, 20 to 30g The body weight is 5%, and 30g weight is 4%.
3.4.2 Feeding principle According to the living habits of grass shrimps, the following principles should be mastered for feeding: 1 Feeding should be done in small quantities every day and evenly.
2 More investment at night, less investment during the day, night feeding amount accounted for 65% of the total daily feeding amount, and the amount of feeding in the day accounted for 35%.
3 When the weather is bad, cast less, and when the weather is good, cast more.
4 The water temperature is higher than 34°C and less than 20°C. When the water temperature is 27 to 31°C, cast more.
5 less water quality investment, a lot of water quality investment.
6 less or no vote when medication, feed deterioration can not vote.
7 The windy weather will not be cast. When shrimps are plucked in large quantities, they will be thrown less.
8 The high temperature season is not fed from 10 a.m. to 16 a.m. daily.
9 The amount of feeding on the first day after the oyster shell should be increased by 20%.
Ten major storms do not vote. When the water quality deteriorates, they do not vote. When the shrimp floats, it does not vote.
3.5 disease prevention and control of disease prevention to prevent. In the early stage, shrimp spirit is used once every 15 days to disinfect once, once every 10 days in the middle period, once every 7 days in the later period, timely disinfected after heavy winds and heavy rains, and water quality abnormally disinfected in time. In addition: pay attention to the regular patrol pond, observe the shrimp's activity, and find the problem in time.
At present, it is difficult to fundamentally solve the current causes of shrimp disease. For example, farmers have paid attention to the problems of the environment and water quality, and neglected to enhance the immune ability of shrimp. Once shrimp diseases are discovered, they hear that they are abusing drugs. In addition, there are many aspects of shrimp disease caused by external factors.
1 Too much rainfall, cloudy days, drastic changes in water temperature, and excessive temperature difference.
2 The sediment quality deteriorates, and harmful algae overproduce.
3 The lack of basic biological feed, poor nutrition of synthetic feeds, slow growth without molting, and reduced disease resistance.
4Environmental deterioration, many pathogenic factors.
5 extensive technical management operations.
6 The seedlings were unhealthy and brought difficulties to farming.
For the above reasons, shrimp aquaculture technicians and farmers believe that effective prevention measures must be taken against the epidemic of shrimp diseases. That is to say, the establishment of a high-health shrimp culture system (HHSS) is referred to as healthy shrimp culture. This is an aquaculture system that combines the breeding of healthy broodstock, the cultivation of healthy shrimp, the comprehensive control of the breeding environment, the selection of high-quality, high-quality feed, and the establishment of a scientific breeding model, so as to effectively prevent the occurrence of diseases. To achieve sustainable development of the shrimp aquaculture industry.
3.6 The timely collection of shrimp mainly focuses on shortening the cycle of shrimp farming. Generally 80 to 90 days of breeding, shrimp ponds up to 40 fish / kg specifications should be promptly received shrimp, to prevent sudden loss of temperature caused by loss.