Hunan Crab Pot Crab is popular among consumers at home and abroad for its rich nutrition and delicious meat. At present, river crabs have become the main aquaculture species in various regions. The crab breeding industry has been transformed from the “large crabs†that pursue yield to the raising of large crabs and the “ecological crabs†centered on quality and efficiency. With the development of the crab breeding industry, crabs with small specifications and poor quality are increasingly not welcomed by consumers. Big size crabs not only sell smoothly, but also have an absolute price advantage. The market price of large size crabs is 3 to 4 times higher than that of small size crabs, and 120 to 160 yuan/kg more than 150g, while the specifications are only about 75g. 30 ~ 40 yuan / kg, but how to cultivate pollution-free production of large-scale crab is a breeder's concern. The so-called large-size crab refers to a crab that has a weight of 150g or more and has "green back, white belly, yellow hair, and gold claws." Through the summarization of many years of production practices, the major breeding techniques for breeding large-scale river crabs are:
First, select good breeds, and put good-quality crab species in quality. Large crabs must have high-quality crab species as a basis. Choosing self-fertilization or local cultivation of Hunan crabs, the Yangtze River water system is robust, disease-free, injury-free, neat specifications, appendages, shiny, strong crabs of Chinese mitten crabs, to avoid the use of unknown sources Juvenile crab, which is the most important factor in breeding crabs and raising the survival rate. Generally, high-quality crab species can be selected from three aspects: identification of crab species in the Yangtze River system from appearance, body type, step-foot, and prefrontal teeth, etc.; “Small Dumpling Crab†refers to the first-instar crab of the year. It weighed between 10 and 35g and reached sexual maturity, stagnant, and died one after another. It was selected from the degree of foot-foot incompleteness, the activity of seedlings, and the presence or absence of parasites on the body surface. High-quality crab species.
Second, planting aquatic plants, creating a good ecological environment As the saying goes, "Crab size, look at aquatic plants." The cultivation of aquatic plants in the waters of Hunan Crab and Crab is one of the best natural botanical feeds for crabs. The second is to provide habitats for crabs and cover their shells. It is not easy to be found by predators and reduce mutual killing. Photosynthesis of plants can increase dissolved oxygen in water and absorb organic matter in water to prevent water quality from eutrophication, which can play a role in purifying water quality, keeping water fresh and improving water culture environment. Fourth, aquatic plants can play in high temperature season. Shading cooling effect, favorable for crab growth, planting aquatic species should not be a single species, to be diversified, the best submerged plants, emergent plants and floating plants combined with each other, a reasonable distribution to meet the various needs of river crab. Submerged plants can be selected species such as Vallisneria, black leaf algae, Elodea, etc., emergent plants such as reeds, alfalfa grass, floating plants such as duckweed and so on. The area for planting aquatic plants in crabs should cover 50% to 60% of the surface area. The summer of July-August is the peak period for crabs to ingest aquatic plants. It is necessary to pay close attention to ensure that crabs are used for food and eat, but also have a high storage capacity. When it is not enough, we must take measures to make up for the aquatic plants. However, weeds should not be caught too much. Corrupt plants may cause water quality deterioration and cause crab disease. Excessive amounts of aquatic weeds, especially those that are similar to Elodea, can easily cause the bottom water body to not flow and cause the bottom water to deteriorate. The water channels should be cleared out in time to facilitate the flow of water into the drainage and improve the water quality of the crab pool. Prone to black spot, edema and other diseases.
Third, control the stocking density, pay attention to reasonable stocking density of crab species, crab species specifications, feeding conditions, listing requirements specifications, management levels, etc., can take two-year breeding mode, is the end of May at the beginning of June to purchase crab seedlings, Extensive breeding in the pool, the end of the year can be bred into crabs, the second year of the spring and then put these crabs to the pool, usually the crab species stocking specifications of 100 to 200 / kg. Each 667 square meters of water stocking 300 to 500, take appropriate release, can improve the crab out of the pool specifications and quality. Crab ponds mainly composed of river crabs cannot be mixed with herbivorous fish (grass carp, group head locust, etc.), omnivorous fish (carp, clam, tilapia, etc.), carnivorous fish (black sea bream, carp, carp And so on), but only mixed filter-feeding fish (eel, squid, etc.). Its purpose is to remove plankton in the water and prevent deterioration of water quality. However, due to the large amount of aquatic plants in the crab pool, the pool water is thinner, so the amount of polyculture should not be much. In general, every 667 square meters of water polyculture 50 ~ 100g / tail white bream, bream species of 40 to 50 tails (porn, squid ratio of 5:1), in addition, crab Hunan crab pool can not be mixed, conditional If so, we can adopt a mode of raising the amount of fresh shrimp in the crab pool and use ecological farming management measures to obtain high yield, high quality, and high efficiency.
Fourth, put snails to meet the needs of river crabs for biological active substances Snails are the most favorite live fresh bait of crabs, snails benthic, slow action, strong water purification capacity, in the crab pond, every 667 square meters of water The live snails 150 to 250 kg are put to let them breed naturally. This will provide a steady stream of palatable and active protein baits for the whole growth process of crabs. Among the various snails, apple snail, one of the finest varieties of individual species cultivated in freshwater snails, can be selected. Apple snails are also called snails. They have thin shells, large individuals, high meat content (38% of body weight of edible ingredients), high food habits, rapid growth, long breeding seasons, and high proliferation times. Transplanting Apple in the Crab Pool The Hunan Crab Lobster can not only maintain the fresh water quality of the crab pond, but also provide the crab with a variety of natural foods rich in various biological active substances, promoting the rapid growth of crabs and increasing the market size of crabs.
New product of U85 micro laser distance sensors use highly focused class 2 laser to detect objects or measure distances, and can return a measured value via varieties intface( serial, usb, rs232, rs485, bluetooth etc.). The electronic distance sensor is a very small Laser Distance Sensor, but high resolution up to 1mm and long distance measuring sensor - teachable measuring range of up to 30m. Extremely accurate distance sensing sensors, errors down to ± 1mm. And the mini sensors and measurements support continuous measurement function, great for compact solutions(eg: robots) with the smallest Laser Distance Sensor of the world!
Parameters of U85:
Accuracy
±1 mm (0.04 inch)
Measuring Unit
mm
Measuring Range (without Reflection)
0.03-20m/0.03-30m
Measuring Time
0.1~3 seconds
Laser Class
Class II
Laser Type
620nm-690nm, <1mW
Size
41*17*7mm (±1 mm)
Weight
About 4g
Voltage
DC2.0~3.3V
Electrical Level
TTL/CMOS
Certifications
CE, FCC, RoHS, FDA
Operating Temperature
0-40 ℃ (32-104 ℉ )
Storage Temperature
-25~60 ℃ (-13~140 ℉)
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