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Key Technical Points for High-Yield and High-Quality Freshwater Shrimp (Macrobrachium nipponense) Aquaculture
(1) Monoculture of freshwater shrimp in ponds. 1. Pond conditions: area of 5-10 mu, water depth of 0.8-1.5 m, firm and leak-proof pond embankments, slope of 1:(2-3), flat pond bottom slightly inclined toward the drainage outlet, and silt not exceeding 20 cm. 2. Preparation before stocking: ① Chemical pond clearing: 7-10 days before stocking, fill with 20 cm of water, apply 100-125 kg of quicklime per mu after slaking, and splash evenly over the entire pond for clearing and disinfection to remove wild fish and harmful organisms; ② Aquatic plant planting: species include Hydrilla verticillata, Potamogeton maackianus, etc., with the planting area accounting for 30-50% of the pond area, then fill with water and fertilize. 3. Water quality management: ① Use microbial preparations: such as EM bacteria, photosynthetic bacteria, etc. From late August to early November, use biological bacteria once every 15 days depending on the medication situation to improve the pond water environment. ② Microporous aeration: equip one 3 kW microporous aeration pump for every 20 mu, lay main pipes parallel to the two long sides of each pond, and install 6 disc-type microporous pipe discs with a diameter of 1.5 m per mu of pond. Dissolved oxygen should be above 5 mg/L. When dissolved oxygen in the shrimp pond falls below 5 mg/L, turn on the aeration pump. Aeration time is generally from 12:00 to 16:00 in the afternoon and from 24:00 at night to 6:00 the next morning, and should be extended on rainy or muggy days. 4. Feeding management: mainly feed complete compound feed for freshwater shrimp of different specifications at different stages, supplemented with rice bran and other feed in the early stage. Feed twice a day, with 1/3 in the morning and 2/3 in the afternoon. Adhere to the "four observations" (observe the season, observe the weather, observe the water color, observe feeding activity) and the "four fixeds" (fixed time, fixed location, fixed quality, fixed quantity). The daily feeding amount is 3-7% of shrimp body weight, and the specific feeding amount should be consumed within 2-3 hours. The feed coefficient for the whole season is 1.5-1.8. (2) Mixed culture of shrimp and crabs in ponds. There is no limit to the pond area, but generally no more than 50 mu is appropriate, with a water depth of 1.0-1.5 m. Pond clearing, disinfection, and grass planting are carried out according to the operating procedures for river crab culture. Stock 5-8 silver carp and bighead carp per mu, put in 200-250 kg of live snails per mu, and plant aquatic plants mainly including Hydrilla verticillata, Potamogeton maackianus, Elodea nuttallii, etc., with the aquatic plant coverage controlled at about 60%. During the growth period of young shrimp in autumn, apply fertilizer appropriately and feed a small amount of powdered feed. When using insecticides and disinfectants, avoid both the peak molting period of river crabs and the peak molting period of freshwater shrimp.</p>
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Five Technical Measures for Disease and Pest Control in Freshwater Shrimp Farming in Summer
Freshwater shrimp outbreaks occur relatively frequently in summer. To reduce farming risks, the following work needs to be done well: 1. Disinfection of shrimp pond water. First, sprinkle dibromohydantoin at 0.25ppm over the whole pond for sterilization, then apply again after an interval of half a month, continuing until early July, for more than 3 consecutive applications, also
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Common Diseases and Predator-Pest Control Techniques in Freshwater Crayfish Farming
Freshwater crayfish rarely suffer from diseases under natural conditions, but with the expansion of high-density artificial farming, freshwater crayfish farming also faces the risk of disease outbreaks. Therefore, the principle of "prevention first" must be adhered to, and disease prevention and control work must be done well. (I) Disease prevention 1. Thorough pond clearing
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Three Key Elements of Scientific Feed Feeding in Macrobrachium nipponense (Freshwater Shrimp) Aquaculture
In the process of Macrobrachium nipponense aquaculture, feed is the input with the largest application amount. Selecting good feed and achieving high utilization rates plays an important role in improving shrimp immunity, preventing shrimp diseases, and optimizing shrimp quality. The following three points should be noted when feeding:
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What are the precautions for freshwater shrimp (Macrobrachium nipponense) farming in spring?
1. Timely split stocking. When the water temperature rises above 20°C, freshwater shrimp begin molting, and at this time the shrimp body is easily bruised and infected. Before stocking, do a good job of drying the pond, and use quicklime, active iodine and other drugs for rapid disinfection; for ponds with moss, green algae, and blue-green algae, spray the entire pond once with copper sulfate.
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Detailed Explanation of New Techniques for Artificial Freshwater Farming of River Crab
River crab, commonly known as crab, also called hairy crab, mitten crab, etc. It belongs to the class Crustacea, family Grapsidae. The cephalothorax is squarish-oval, generally 6-7 cm long, usually green. The chelipeds are powerful and densely covered with downy hair, and the walking legs are flattened laterally and long. Wild river crabs live in the muddy beaches of the embankments of rivers, lakes and marshes,
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What are the points to note when stocking freshwater crayfish?
In recent years, crayfish have become a darling of the dining table, with their value multiplying. It is predicted that the crayfish market will not become saturated within the next 5 years, and crayfish farming is rapidly expanding in various places. After several years of production practice, the author believes that the following points should be noted when stocking crayfish:
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Overwintering techniques for freshwater pomfret fry
The freshwater pomfret (Piaractus brachypomus) is a freshwater aquaculture fish species introduced to mainland China for farming in the 1980s. Because of its good meat quality, fast growth, ease of extensive rearing and large market demand, it is deeply favored by the vast number of farmers. However, since the freshwater pomfret is a warm-water fish, its optimal growth
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Key Technical Points for Nursing Summer-Fingerlings of Freshwater Pompano
Freshwater pompano fry reared for about 20 days, with a body length of about 3 cm, are called summer-fingerling fish. The key nursing techniques at this stage are as follows: 1. Pond selection. The pond should have abundant water sources, good water quality free of pollution, good light, and convenient water intake and drainage, with a length-to-width ratio of 3:
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Common Winter Disease Prevention and Treatment Methods for Freshwater Piranha
In winter, when the water temperature is between 15°C and 20°C, juvenile freshwater piranha are prone to Ichthyophthirius disease, white skin disease, and Dactylogyrus disease. During overwintering, freshwater piranha are prone to saprolegniasis, water mold disease, and Trichodina disease. The symptoms and prevention and treatment methods for these diseases are introduced below
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