CATDOLL : CATDOLL: What do crayfish like to eat?

1. What do crayfish like to eat?

Crayfish are omnivores, and they like to eat a lot of food. Like other animals, lobsters like fresh, nutritious, and delicious food. Lobsters like to eat aquatic insects, mosquito larvae, dragonfly larvae, small fish and shrimps, earthworms, maggots, etc. Artificially raised animal baits that are high in protein, comprehensive in nutrition, and good in palatability include clam meat, snail meat, animal offal, livestock and poultry meat, earthworms, mealworms, fly maggots, etc. Lobsters' favorite plant baits include phytoplankton such as green algae, filamentous algae, duckweed, and freshwater plants. The favorite plant baits for domesticated crayfish are tofu dregs, bran, corn flakes, rice bran, various fruits and vegetables, etc.

Crayfish like to eat plankton. Although heavy metals, oil and other garbage are not the food of crayfish, they can attach to food and enter the body of crayfish. If crayfish live in water polluted by heavy metal ions, it is difficult for them to excrete the "poison" in their bodies.

Farming technology

In nature, lobsters mainly live on the sandy and muddy seabed, with one lobster hiding in each hole. However, during the mating season, male and female lobsters hide together, sometimes hiding in the gaps between rocks to mate. Japanese lobsters live in groups. Lobsters must be fed during the breeding period, and it is necessary to consider whether various attached organisms can be used as bait.

1. Water temperature: Lobsters live in relatively low water temperatures. The lowest water temperature in winter is about 5℃-6℃, which is suitable for lobster farming. If the water temperature is low, the maturity period will be extended to 5-7 years. Lobsters have poor tolerance to high temperatures. In the experiment, the water temperature was raised to 25℃ and continued for 2 weeks without any abnormal phenomena. According to the experiment, the suitable temperature for growth is 20℃-23℃. Lobsters grow fastest in water with a temperature of 20℃-22℃. Therefore, in the winter when the water temperature drops, using warm drainage for breeding is one of the ways to promote growth.

2. Salinity: The suitable salt range for lobsters is 26.90‰-34.40‰. They can also live and metamorphose in seawater with a low salinity of 23.50‰.

3. Bottom: After metamorphosis, lobster larvae turn to bottom-dwelling life to avoid being preyed upon by natural enemies. The gravel of the bottom is extremely important as a place to hide and forage. After 3-4 days of metamorphosis, lobsters can dig holes and hide in sand with a particle size of 0.4-1.00 mm. After 8 days of metamorphosis, they can hide in sand with a particle size of 2.0-3.0 mm.

4. Growth rate: For lobsters under 1 year old, it is only necessary to use oyster shells to cover the bottom of the pond, and there is no need to place artificial shelter nests. Blue mussels are fed as bait. From the 2nd age, tetrachloroethylene tubes are placed as shelter nests, and the number of them placed is twice the number of lobsters raised. In the group that has been cultured for 2 years, the largest individual weighing about 300 grams appears. Each time the lobster molts, it gains about 50% of its weight. When the lobster individual molts at the beginning of the first year, the weight can reach 450 grams when it reaches sexual maturity. In the 3-year-old group, 16% have reached sexual maturity.

The growth of lobsters is related to the bait, environment, water quality and the number of times they molt. Various baits and electrical stimulation for molting have been tested. The results show that fresh shrimp meat feeds them faster, twice as fast as fish meat feeds. During the growth process, they usually molt more than twice a year. When chemical drugs or electrical stimulation are used, they can molt four times, and the growth rate increases by 1 time. After molting, the new shell hardens after 2 weeks, and the lobster will become active again. At this time, the appetite increases greatly, and the amount of feed must be increased by 30% when feeding.

5. Survival rate: Based on the benthic stage IV larvae, the survival rate of groups less than 1 year old is slightly lower than 60%, but the survival rate of groups aged 1-3 years exceeds 80%. A survival rate of 80% in group rearing is a relatively good breeding result.

It was observed that lobsters that encountered each other in the pond often lifted their claws to intimidate each other, but there was no phenomenon of fighting with claws that resulted in the death of lobsters. Therefore, it is believed that it is more efficient to raise lobsters aged 0-1 in groups and to raise them in isolation as individuals after the age of 2.

6. Feed: After the IVth stage, lobsters are specially fed with purple mussels, which can promote the rapid maturity and reproduction of lobsters. Purple mussels can meet the nutritional needs of lobsters. Lobsters have a mixed diet and can be fed with frozen small fish, small shellfish and artificial shrimp bait. Feed once a day, preferably in the afternoon, feed for 2 consecutive days and stop for 1 day, and the daily feed amount is 5%-12% of the shrimp weight. Always pay attention to the activities and feeding conditions of lobsters, and clean the pond once a year to prevent pollution. Experiments have shown that the growth and survival rate of lobsters fed with Japanese shrimps are better than those fed with purple mussels. For lobsters, the most suitable protein content in the feed is 20%-25%. It is hoped that a compound bait suitable for lobsters can be developed in the future. In addition, lobsters use the third palatine foot to prey on granular bait, so the individual size of lobsters has no direct relationship with the size of the particles, and generally small-diameter granular feed can be used.

You can feed lobsters omnivorous food, they will eat everything.

But Naxian should pay attention to the fact that the dried small fishes should be soaked in water to soften them, and the vegetables should be blanched in water before feeding.

In addition, you can put live small fish in the water tank and the fish will catch food on its own.

You can also feed them with feed. Lobsters have a mixed diet, so you can feed them with frozen small fish. Always pay attention to the activities and feeding conditions of lobsters, change the water frequently, and put some water plants and mud in the water. That's it!

They eat artificial mixed bait and humus, which is easy to feed. They are mainly fed with minced small fish and minced meat. In the next month, small fish, scraps or artificial mixed baits are added. When the shrimp fry grows to 6-7 cm, they can be fed with crushed snails, river clams and appropriate amounts of plant bait. The daily feeding amount is based on the amount of food they eat.

They have strong survival abilities and are omnivorous, eating a wide variety of foods, both meat and vegetables. Even the seedlings in rice fields are their food.

2. What to do if you eat prawns with maggots

If your body's resistance is strong, there is no problem. If it is weak, you will vomit and have diarrhea.

3. When Japanese people eat sushi, aren't they afraid that raw fish and shrimp may contain bacteria and insects?

Hygiene of the sea areas for aquaculture is one of them.

In fact, a lot of sushi vinegar is used in sushi, which has a sterilizing effect.

Can reduce bacteria during the production process

Usually served with vinegar and ginger

This will ensure greater safety

Also, ginger is hot in nature, so some people who have diarrhea after eating raw food can also eat sushi.

4. Questions about maggots

Yes, some maggots are edible. For example, raw maggots from meat are a special delicacy. Raw maggots from Northeast China can be used as a medicine. But maggots from toilets are not edible because they are... raw maggots. I have given the first two examples, and you should understand, right?

5. Delicious Japanese Prawn Dishes

Dry-fried prawns

Main ingredients: 6 prawns (0.5 kg)

Seasoning: refined oil, Maggi soy sauce, tomato sauce, wine, salt, sugar, onion, ginger, garlic

practice:

⒈Wash the prawns, remove whiskers and legs, and drain;

⒉ Chop garlic, ginger and onion into fine pieces for later use;

⒊ Put the pan on low heat, add a little oil, heat it to 50%, add the prawns, turn and fry both sides, add the minced garlic and ginger after 5 minutes (be careful not to burn them), and continue frying until 90% cooked;

⒋ (Cook on low heat at this time) Pour in wine, Maggi soy sauce, tomato sauce, sugar, and a little salt, turn over and fry both sides. After 5 minutes, remove from the pan and serve on a plate, sprinkle with chopped green onion.

Penaeus prawns

Ingredients: 500g prawns

Accessories: 200g eggs

Seasoning: 5g cooking wine, 5g salt, 3g pepper salt, 1g MSG, 15g green onion, 10g ginger, 2g pepper, 10g starch (broad bean), 100g peanut oil

practice:

⒈ Wash and chop the green onion and ginger, put them into a gauze bag, squeeze out the water, and discard the residue.

⒉ Wash the prawns, peel them (leave the tail shell on), remove the sand intestines, scrape off the black spots on the tail, split the spine, cut the tendons and put them in a bowl, add onion and ginger juice, white pepper, salt, Shaoxing wine, and MSG, marinate for 10 minutes, take out and use a clean cloth to absorb the surface moisture.

⒊ Beat the eggs into a bowl and mix well, then add dry starch and stir into egg batter.

⒋ Heat the wok on high heat, add peanut oil and heat it until it is 60% hot. Dip the shrimp tails one by one in the egg batter (do not dip the tail shell in the batter) and put them into the wok. Turn them over gently. Fry until golden brown. Pour into a colander to drain the oil, place on a chopping board, slice each one diagonally twice (keep the original shape), serve on a plate, sprinkle with pepper salt and serve.

Saltwater shrimp

Ingredients: 1 kg of prawns

practice:

1: Just wash the prawns a few times after you buy them. The boss said that you don’t need to remove the black lines for this kind of prawns, so I didn’t do that. But you must buy fresh prawns, as they will taste better that way.

2: Boil water in a pot, add ginger slices, green onions, cooking wine and 2 teaspoons of salt and cook for two minutes.

3: After two minutes, pour in the washed prawns.

4: Cook over high heat for 3 to 4 minutes and then remove from the heat. It is good to dip it in vinegar when eating. This dish is probably the best dish for housewives to make. It is simple and delicious. People who are away from home may also want to make it once.