CATDOLL : CATDOLL: Will maggots appear when crayfish die?

Will maggots appear when crayfish die?

Maggots are the larvae of flies. Whether or not maggots will appear depends on whether there are flies. If there are, there will be maggots; if not, there will not be maggots. It is just like drying bacon in the south in winter. You have to wait until there are no mosquitoes and flies.

Of course.

Crayfish breeding technology

condition

Crayfish are extremely adaptable and have a wide range of suitable growth temperatures. They can grow normally in water temperatures between 10 and 30 degrees Celsius. They are also resistant to high temperatures and severe cold, and can withstand temperatures above 40 degrees Celsius, and can also safely overwinter in temperatures below -14 degrees Celsius.

Crayfish have strong adaptability to the environment and can grow in various water bodies such as lakes, ponds, ditches, rice fields, etc. The water source must be sufficient and the water depth must be about 1 meter.

The pond must have sufficient water, good water quality, convenient water inlet and outlet, and the area is generally 3 to 5 mu. The pond ridge should have a certain slope, and in order to prevent crayfish from digging holes and escaping, the width of the pond ridge should be more than 1.5 meters, and a 0.5-meter-high, smooth-walled anti-escape wall or anti-escape board should be set around the pond ridge. Build some mud ridges in the middle of the pond to provide a place for crayfish to dig holes. Note that the mud ridge is not connected to the pond ridge at both ends. The length of the mud ridge is about 4/5 of the length of the pond, the width of the ridge is more than 1 meter, and the ridge is 5 to 10 cm above the water surface. The depth of the pond water should be 0.8 to 1.5 meters, preferably in the middle of the water depth, with shallows around, and tree roots, bamboo tubes, etc. placed at the bottom of the pond. Strict disinfection should be carried out before stocking, and 300 to 500 kg of decomposed livestock and poultry feces should be applied per mu. Aquatic plants, such as Vallisneria, Hydrilla verticillata, Eichhornia crassipes, Pistia ovata, and Water Peanut, are planted in the pond, accounting for 30% of the pond area, to provide a convenient habitat for crayfish when they molt.

Water Transfer

1. Reasonably adjust the water quality every half a month or so

Alternately use photosynthetic bacteria and quicklime to spray the whole pond to improve water quality, adjust the pH value of the water body, and reduce the ammonia nitrogen content in the pond. In addition, apply calcium dihydrogen phosphate regularly to increase the content of ion calcium in the pond water to promote the molting and growth of crayfish. The dosage of calcium dihydrogen phosphate is generally 2 kg/mu/m. When there is external water injection and replacement, new water is injected every 10 to 15 days, and the amount of water replaced each time is about 1/3 of the original pond water volume.

2. Pay attention to the environment at the bottom of the pond. When the weather is bad, reduce the amount of feeding or stop feeding, and pay attention to observation, remove the remaining bait and debris in the pond in time to keep the pond clean. If the lobsters are found to be slow to react and swim to the shore and climb up, it means that they are lacking oxygen. You should turn on the aerator to increase oxygen or add new water in time.

3. Timely prevention and control of diseases. Prevention is the main approach to disease prevention. While regularly disinfecting the water body, multivitamins, calcium tablets and other drugs should be added to the feed to enhance the immunity of crayfish.

4. Adding shelter Planting aquatic plants in the breeding pond can serve as a habitat and shelter for lobsters, and is also a palatable bait for lobsters. It not only saves breeding costs, but also plays a role in regulating water quality. The area of ​​aquatic plants generally accounts for 1/3 of the water surface area.

5. Lobsters grow fast, have an active metabolism, and consume a lot of oxygen, so the water in the shrimp pond must be kept fresh. Add 15 to 20 centimeters of water every week to ensure that the water is fresh, clean, and has sufficient dissolved oxygen. The transparency of the pond water should be controlled at a depth of more than 35 centimeters. When the weather is too hot, the pond water should be deepened appropriately to stabilize the water temperature.

Management methods

Inspect the pond every day and deal with problems in time. Apply fertilizer in time. One week after the shrimp fry are released, apply 50 kg to 60 kg of decomposed livestock and poultry feces per mu. In the middle and late stages of breeding, apply 15 kg to 20 kg of fermented feces fertilizer per mu every half a month. Keep the pond water bean green or brown, with a transparency of about 35 cm. Frequently add new water. Change the water every 5 to 7 days in high temperature seasons and every 15 to 20 days in normal times. The amount of water changed each time is 20% to 30% of the pond water. Keep the pH value of the pond water between 7 and 9, and the dissolved oxygen content greater than 4 mg/L. Disinfect and improve the water body regularly. Use 10 to 15 kg of quicklime per mu and spray it throughout the pond once every 15 days. Use 0.5 to 0.6 grams of bleaching powder per cubic meter of water and spray it throughout the pond every month. In the middle and late stages of aquaculture, use 5 to 6 grams of photosynthetic bacteria and 40 to 60 grams of bottom improver per cubic meter of water and spray it throughout the pond every month to maintain a good water environment.

Do crayfish really contain parasites? Can they still be eaten?

Crayfish (|mantis crayfish) and crabs are the second intermediate hosts of lung fluke. Adult lung fluke parasitizes the lungs or other tissues of humans and mammals. The eggs produced by adult worms parasitizing the lungs can be coughed out with sputum through the trachea or enter the digestive tract and be excreted with feces. After about 20 days in the water, the eggs develop into mature miracidia and hatch. The miracidia invade the first intermediate host (freshwater snails such as Sichuan spiral snails and Oncomelania hupensis), and asexually reproduce in the snail body through the stages of sporocysts, mother redia, and daughter redia. After about 3 months, a large number of cercariae are formed. The mature cercariae escape from the snail body and invade the second intermediate host (crabs and|mantis crayfish) or are swallowed by the second intermediate host along with the snail body. The cercariae form metacercariae in the muscles or internal organs of the second intermediate host. Hazards: When people eat raw or half-cooked crabs or crayfish containing metacercariae, the metacercariae enter the human body, exuviate the cysts in the human intestine and become larvae, which pass through the intestinal wall and migrate in the abdominal cavity, abdominal wall and other tissues and organs. The larvae finally reach the lungs and develop into mature adults, thus causing severe paragonimiasis in humans. Paragonimiasis involves multiple tissues and organs, and its clinical manifestations are varied and complex as the disease progresses.

Crayfish have a very diverse diet. In addition to plant stalks and water plants, they also feed on dead fish or the bodies of their own kind. Because they have the habit of eating rotten corpses, they carry a large number of bacteria and toxic substances in their bodies. Some vendors catch crayfish grown in the wild and transport them to the market without quarantine to sell at low prices. Some vendors deliberately feed unclean feed into the breeding ponds, and even use polluted ponds and swamps as breeding grounds.

The waters where crayfish live are filled with large amounts of plankton. Whether they are farmed or wild, crayfish are hosts to parasites.

Current research data shows that crayfish generally do not have parasites. Some people believe that crayfish contain parasites, namely lung fluke metacercariae, which can cause emphysema after eating. This is just an unfounded guess.

First of all, crayfish contains extremely high protein and trace elements such as zinc, iodine, and selenium. It is rich in nutrients, and its meat is soft and easy to digest. It is an excellent food for people who are weak or need recuperation after illness.

Although crayfish have parasites, you can eat them as long as you wash them clean, fry them at high temperature, or cook them for a longer time.