The puffer fish is distributed all over the world, with about 100 species. The puffer fish has a small round mouth, a dark brown back and a white abdomen. The big one is 1 m long and weighs about 10 kg. Its eyes are usually blue-green, which can automatically change color with the change of light. Not many bones', dorsal fin and ventral fin are very soft, but there are two rows of sharp teeth, which can crush hard-shell foods such as clams, oysters and sea urchins.
Although puffer fish is highly toxic, its meat is delicious and tender. People often compare puffer fish slices with Japanese paintings, which are soft, delicate and memorable.
The puffer fish meat contains less toxins, while the ovary, liver and blood all contain more toxins. In China, in order to protect people's lives, the state explicitly prohibits restaurants from serving puffer fish. Japan has a long history of eating puffer fish, which has almost become an important part of its food culture. The processing of puffer fish is very strict. A qualified puffer fish chef must receive at least two years of rigorous training and pass the examination before obtaining a business license. Each puffer fish needs to go through 30 procedures to detoxify, and a skilled chef needs 20 minutes to complete it. Pufferfish are usually kept in ponds. Before eating, net it out with a net bag, cut off the fins, cut off the mouth, gouge out the fish eyes and peel off the fish skin with a knife. Then, cut them open, take out the highly toxic internal organs such as intestines, liver, ovaries and kidneys, and then cut the meat of puffer fish into small pieces and put them in clean water to wash away the poison. The washed fish pieces are as white as jade and crystal clear. Next, cut it into pieces as thin as paper, and then arrange these fish slices into patterns such as chrysanthemums or cranes. When eating, pick up the fish fillet and dip it in the soy sauce and pepper on the plate and chew it slowly in your mouth. After eating fish fillets and drinking a bowl of puffer fish soup, it is really refreshing and delicious.
Although puffer fish meat is delicious, improper handling or overeating will kill people. Tetrodotoxin is a neurotoxin, which is nearly a thousand times more toxic than potassium cyanide. In Japan, people die every year because of eating tetrodotoxin by mistake.
Like snake venom, bee venom and other toxins, tetrodotoxin also has its beneficial side. The liver extract of puffer fish has inhibitory effect on many tumors. Dolphin liver fraction has been made into tetrodotoxin injection for clinical and surgical analgesia of cancer.
2. Puffer information
Puffer fish, also known as "bubble fish".
It was called hóu tái in ancient times, also known as puffer fish, bubble fish and spicy fish. In Jiangsu and Zhejiang provinces, it is called small fish plate, Big Fish Board and Goro, and in Guangdong Province, it is called Yayu. Pufferfish look like river fish, but in modern animal taxonomy, they are divided into different aquatic animals.
The puffer fish has a short and thick body. Pufferfish have very thin spines.
Tough and thick puffer fish skin was once used to make helmets. The teeth, maxilla and mandible of puffer fish are distinguished and connected together like two sharp blades.
This allows puffer fish to crush hard coral shells at will. Most puffer fish are tropical marine fish, as long as a few species live in fresh water.
Once the puffer fish is threatened, it will swallow water or air to expand its body into a spiny ball, making it difficult for natural enemies to speak. The viscera of many puffer fish contains a neurotoxin that can kill people.
Someone has tested the toxicity of tetrodotoxin. Its toxicity is equivalent to 1250 times of the highly toxic drug sodium cyanide! It only takes 0.48mg to kill! In fact, the muscles of puffer fish are toxin-free.
The most poisonous parts of puffer fish are ovary and liver, followed by kidney, blood, eyes, gills and skin. The toxicity of puffer fish is very small, which is also related to its breeding cycle.
The puffer fish with eggs is the most toxic in late spring and early summer. This toxin can make people numb, vomit, and feel cold in their limbs, thus stopping their heartbeat and breathing.
There are reports of eating puffer fish and dying at home and abroad. Of course, you have to risk your life to taste puffer fish, but that's because puffer fish tastes delicious.
So there are still many gluttons who desperately eat puffer fish.
3. A few small questions about puffer fish
Common names of puffer fish, ichthyidae and porpoises.
The body is cylindrical, and the more teeth are combined into dental plates. A dorsal fin, no ventral fin.
Scaleless or spiny. There is an airbag that can be inflated by inhalation.
There are many kinds, some of which will enter fresh water. The puffer fish meat is delicious, and only the liver, gonads and blood contain toxins. After processing, it can be eaten or made into frozen fish fillets and canned food.
After pickling, it is commonly known as "black wolf owl". Ovary can make medical tetrodotoxin; Skin can be made into fish skin glue; The liver can extract puffer fish oil; Sperm ovary can produce protamine; Bones can be used to make fish meal.
There are generally four kinds of poisonous puffer fish in our province: oriental dolphin with insect stripes, oriental dolphin with horizontal stripes, oriental dolphin with lead spots and spiny dolphin with moon belly. Wormlike striped oriental dolphin: the dorsal surface is smooth and spineless, the dorsal surface is grayish brown, with wormlike white patterns, small spots on the chest, white spots around it, and yellow longitudinal bands under the side.
It is a small species with a total length of about 30 cm. Striped fugu orientalis: The ventral and lateral parts are densely covered with tiny bundles, the dorsal part is dark brown, with many thin and light horizontal bands, and there is a yellow longitudinal band below the lateral part, with a total length of 25 cm, and it is small and medium-sized.
Lead-spotted Oriental Dolphin: There are small spines on the back and abdomen, yellow-brown back with small spots, 5-6 dark brown horizontal bands and a yellow vertical band under the side, with a total length of 25 cm. It is a small species. Spinibarbus lunata: The mask of the whole back and abdomen is strong mucro, the back is brownish green, the tail fin is grayish brown or yellow, and it is crescent-shaped, with a total length of 50 cm. It is a medium-sized species.
Tetrodotoxin: The liver, spleen, kidney, ovary, testis, eyeball, skin and blood of puffer fish are all toxic. Eggs, ovaries and liver are the most toxic, followed by kidneys, blood, eyes and skin.
This toxin is heat-resistant and will not be destroyed by salting and sun exposure. Toxins mainly paralyze nerve centers and nerve endings.
Poisoning manifestations: tetrodotoxin poisoning is an emergency caused by eating puffer fish. Symptoms such as nausea, vomiting, abdominal pain or diarrhea appear after poisoning. At first, there may be numbness in the lips, tongue tip and fingers, then numbness in the whole body, drooping eyelids, weakness in limbs, unstable walking and imbalance in supply. In severe cases, there will be dyspnea, blood pressure drop, speech disorder, coma, and finally death from respiratory and circulatory failure.
Efficacy tetrodotoxin has magical analgesic effect. A molecule decomposed from tetrodotoxin can organize nerves to send pain signals to the brain, thus playing an analgesic role.
This kind of painkiller made of tetrodotoxin is different from other painkillers. It will not produce side effects, react with other drugs and be addictive, but its analgesic effect is extremely obvious, which is 3200 times that of morphine. Puffer fish cuisine 1, sashimi: Choose puffer fish with its head and skin removed, cut off the muscles on both sides of its spine, make sashimi with a raw fish knife, put it in a container to make a pattern, and add seasonings made of pepper, radish sauce and green grapefruit sauce.
2. Blowfish Hotpot: kelp stew soup is selected as the base soup, and blowfish skull, fish steak, Bai Zi, onion, Flammulina velutipes, Chinese cabbage and tofu can all be put into the pot. Finally, cook porridge with rice, and pour laver, chopped green onion and eggs with water. 3. Fried puffer fish:-Tempura is wrapped on the surface of puffer fish meat, fish steak, mushrooms, chrysanthemums, eggplant and so on with the unique starch of Tempura. Deep-fried with warm peanuts and seasoned with radish mud soup.
4. Frozen puffer fish skin: stew the processed puffer fish skin with water until it is dissolved, then remove impurities with gauze, put it in the shade until it freezes, and season it with shallots and soy sauce. 5. Puffer fin wine: bake the air-dried puffer fin to a burnt state with warm fire, heat Japanese sake to 80℃, and soak the fin in wine to make fin wine.
6. Braised puffer fish: Boil the detoxified puffer fish with water, noodle sauce, onion, ginger, bamboo shoots and mushrooms for 10- 15 minutes, and then take it out of the pot. 7. Stewed puffer fish: put the detoxified puffer fish into a steamer, and add onions, ginger, pork belly and peppers. Steam for 8- 10 minutes.
8. Ginseng, Zanthoxylum bungeanum and puffer fish soup: Put the processed and detoxified puffer fish into the oil for stewing, then add ginseng filaments and red pepper slices, and simmer on low heat until the soup is red. The puffer fish wine is Shi's milk wine, the puffer fish wine is shark fin wine, the puffer fish wine is body wine, and the puffer fish wine is bone wine.
Braised puffer fish is characterized by fresh and salty taste and strong sauce flavor, and the ingredients are cabbage or bamboo shoots. Mussels.
Lentils and so on. The taste is mainly salty and sweet, which is a typical flavor of Huaiyang cuisine. Please note that the skin of braised puffer fish is generally liked by both the host and the guests. Other fish and liver, ingredients and fish are divided according to people. Fish soup can also be removed and replaced with rice if customers need it. The puffer fish in milk soup is characterized by fresh, fragrant and thick soup, and the ingredients are yam, radish, bamboo shoots and mushrooms.
It tastes like braised pork. Finally, if there is more fish soup, it can also be fish soup with rice. Sashimi puffer fish is a masterpiece of Japanese state banquet dishes. Eat one fish and two fish. Fish fillets are white and thin, smooth and refreshing. You need to catch up with this delicious dish for a while. The seasoning plate consists of Japanese edible oil and Japanese mustard.
Fish fillets will sit longer than fish soup in the morning. Fish is eaten like other sashimi.
Fish soup has two parts, just like milk soup. But the key is to eat puffer fish sashimi, don't drink strong liquor, and drink Japanese sake.
4. Little knowledge about dolphins
Dolphins are small to medium sized whales. It is about 1.5~ 10 m long and weighs 50~7000 kg. Males are usually bigger than females. Most dolphins have unique head characteristics. Because of the existence of bean-like fat, the forehead before the beak bulges, which is also called "forehead bulge" This structure helps to collect echolocation and foraging sounds.
Although some dolphins have long foreheads, their beaks are short, and the raised foreheads only outline a square appearance. Most dolphins have smooth bodies and hooked dorsal fins (among other forms). Some dolphins have striking color patterns, while others are monotonous colors.
Dolphins don't dive as long as other whales. Swim fast, with the characteristics of juggling. Dolphin swimming is a unique swimming style of dolphins. The whole body jumps out of the water at a small angle and then enters the water at a small angle, which is one of the ways that dolphins are different from other cetaceans (porpoises and other cetaceans generally do not swim in this way).
Dolphins swim very fast, usually the fastest speed is about 30-40km/h, and the speed of some kinds of dolphins can exceed 55km/h and last for a long time. They are champions of long-distance ocean swimming.
As mammals, dolphins have many characteristics similar to humans. However, because dolphins live in the sea, they are born in a slightly different way from human land environment. When young porpoises are born, their tails come out first, while human babies come out first. Female dolphins usually have to be pregnant 1 1 month to give birth to their cubs.
Extended data:
Overview of species
1, bottlenose dolphin
Bottlenose dolphins, also known as bottlenose dolphins, bottlenose dolphins, bottlenose dolphins and giant dolphins. Widely distributed in temperate and tropical oceans such as Atlantic Ocean, Indian Ocean, Pacific Ocean, Mediterranean Sea, Black Sea and Red Sea. , and often active in the shallow sea area near the land. Bottlenose dolphins are friendly, lively and curious. Bottlenose dolphins are relatively safe under current living conditions. However, due to climate change or human hunting and environmental pollution, the survival of individual populations is also threatened.
2. Short-nosed dolphins
Short-nosed dolphin, also known as dolphin or puffer fish, is a kind of dolphin scattered in the Bay of Bengal and the coastal and rivers of Southeast Asia. They swim slowly, but the maximum speed is 20-25 kilometers per hour. Dolphins mainly eat radial fin fish and fish eggs, cephalopods and crustaceans. They can suck food with their mouths.
3. Gray Dolphin
Gray dolphin, distributed in tropical to temperate waters all over the world, usually moves in deep water. They mainly feed in the mixed area of offshore and offshore, especially in the water layer between 600 and 800 meters. Their diet includes small squid, fish, krill, crustaceans and cephalopods, and the main food is large octopus.
4. Real dolphins
True dolphins, also known as short-nosed true dolphins and common dolphins, belong to the genus Dolphin of Dolphinidae, and are mostly found in tropical to temperate waters. It is often a group of dozens or hundreds of fish, very attached and fast-moving, and feeds on fish and squid, especially group fish.
5. Freund's dolphin
Freund's dolphin, the only animal belonging to the genus Dolphin, is mainly distributed in the deep Pacific Ocean, but also appears in the Indian Ocean and Atlantic Ocean, mostly in tropical waters. The type of this species is in Borneo. Dozens to hundreds of heads swim in groups, even thousands. Feeding on fish, shrimp, crustaceans and squid.
Sogou encyclopedia-dolphins
5. A few small questions about puffer fish
Common names for puffer fish, ichthyidae and porpoises.
The body is cylindrical, and the more teeth are combined into dental plates. A dorsal fin, no ventral fin.
Scaleless or spiny. There is an airbag that can be inflated by inhalation.
There are many kinds, some of which will enter fresh water. The puffer fish meat is delicious, and only the liver, gonads and blood contain toxins. After processing, it can be eaten or made into frozen fish fillets and canned food.
After pickling, it is commonly known as "black wolf owl". Ovary can make medical tetrodotoxin; Skin can be made into fish skin glue; The liver can extract puffer fish oil; Sperm ovary can produce protamine; Bones can be used to make fish meal.
There are generally four kinds of poisonous puffer fish in our province: oriental dolphin with insect stripes, oriental dolphin with horizontal stripes, oriental dolphin with lead spots and spiny dolphin with moon belly. Wormlike striped oriental dolphin: the dorsal surface is smooth and spineless, the dorsal surface is grayish brown, with wormlike white patterns, small spots on the chest, white spots around it, and yellow longitudinal bands under the side.
It is a small species with a total length of about 30 cm. Striped fugu orientalis: The ventral and lateral parts are densely covered with tiny bundles, the dorsal part is dark brown, with many thin and light horizontal bands, and there is a yellow longitudinal band below the lateral part, with a total length of 25 cm, and it is small and medium-sized.
Lead-spotted Oriental Dolphin: There are small spines on the back and abdomen, yellow-brown back with small spots, 5-6 dark brown horizontal bands and a yellow vertical band under the side, with a total length of 25 cm. It is a small species. Spinibarbus lunata: The mask of the whole back and abdomen is strong mucro, the back is brownish green, the tail fin is grayish brown or yellow, and it is crescent-shaped, with a total length of 50 cm. It is a medium-sized species.
Tetrodotoxin: The liver, spleen, kidney, ovary, testis, eyeball, skin and blood of puffer fish are all toxic. Eggs, ovaries and liver are the most toxic, followed by kidneys, blood, eyes and skin.
This toxin is heat-resistant and will not be destroyed by salting and sun exposure. Toxins mainly paralyze nerve centers and nerve endings.
Poisoning manifestations: tetrodotoxin poisoning is an emergency caused by eating puffer fish. Symptoms such as nausea, vomiting, abdominal pain or diarrhea appear after poisoning. At first, there may be numbness in the lips, tongue tip and fingers, then numbness in the whole body, drooping eyelids, weakness in limbs, unstable walking and imbalance in supply. In severe cases, there will be dyspnea, blood pressure drop, speech disorder, coma, and finally death from respiratory and circulatory failure.
Efficacy tetrodotoxin has magical analgesic effect. A molecule decomposed from tetrodotoxin can organize nerves to send pain signals to the brain, thus playing an analgesic role.
This kind of painkiller made of tetrodotoxin is different from other painkillers. It will not produce side effects, react with other drugs and be addictive, but its analgesic effect is extremely obvious, which is 3200 times that of morphine. Puffer fish cuisine 1, sashimi: Choose puffer fish with its head and skin removed, cut off the muscles on both sides of its spine, make sashimi with a raw fish knife, put it in a container to make a pattern, and add seasonings made of pepper, radish sauce and green grapefruit sauce.
2. Blowfish Hotpot: kelp stew soup is selected as the base soup, and blowfish skull, fish steak, Bai Zi, onion, Flammulina velutipes, Chinese cabbage and tofu can all be put into the pot. Finally, cook porridge with rice, and pour laver, chopped green onion and eggs with water. 3. Fried puffer fish:-Tempura is wrapped on the surface of puffer fish meat, fish steak, mushrooms, chrysanthemums, eggplant and so on with the unique starch of Tempura. Deep-fried with warm peanuts and seasoned with radish mud soup.
4. Frozen puffer fish skin: stew the processed puffer fish skin with water until it is dissolved, then remove impurities with gauze, put it in the shade until it freezes, and season it with shallots and soy sauce. 5. Puffer fin wine: bake the air-dried puffer fin to a burnt state with warm fire, heat Japanese sake to 80℃, and soak the fin in wine to make fin wine.
6. Braised puffer fish: Boil the detoxified puffer fish with water, noodle sauce, onion, ginger, bamboo shoots and mushrooms for 10- 15 minutes, and then take it out of the pot. 7. Stewed puffer fish: put the detoxified puffer fish into a steamer, and add onions, ginger, pork belly and peppers. Steam for 8- 10 minutes.
8. Ginseng, Zanthoxylum bungeanum and puffer fish soup: Put the processed and detoxified puffer fish into the oil for stewing, then add ginseng filaments and red pepper slices, and simmer on low heat until the soup is red. The puffer fish wine is Shi's milk wine, the puffer fish wine is shark fin wine, the puffer fish wine is body wine, and the puffer fish wine is bone wine.
Braised puffer fish is characterized by fresh and salty taste and strong sauce flavor, and the ingredients are cabbage or bamboo shoots. Mussels.
Lentils and so on. The taste is mainly salty and sweet, which is a typical flavor of Huaiyang cuisine. Please note that the skin of braised puffer fish is generally liked by both the host and the guests. Other fish and liver, ingredients and fish are divided according to people. Fish soup can also be removed and replaced with rice if customers need it. The puffer fish in milk soup is characterized by fresh, fragrant and thick soup, and the ingredients are yam, radish, bamboo shoots and mushrooms.
It tastes like braised pork. Finally, if there is more fish soup, it can also be fish soup and rice. Sashimi puffer fish is a masterpiece of Japanese state banquet dishes. Eat one fish and two fish. Fish fillets are white and thin, smooth and refreshing. You need to catch up with this delicious dish for a while. The seasoning plate consists of Japanese edible oil and Japanese mustard.
Fish fillets will sit longer than fish soup in the morning. Fish is eaten like other sashimi.
Fish soup has two parts, just like milk soup. But the key is to eat puffer fish sashimi, don't drink strong liquor, and drink Japanese sake.
6.
Principle 1: Reduce their pressure as much as possible. Stress will destroy their immune system and make them easy to get sick. Establishing a comfortable family and living environment for them is a good way to relieve stress.
You might as well arrange something for them to hide in the jar. Aquatic plants with broad leaves, caves and heavy wood are all good choices. These little guys are more active at dusk and night, and generally like to hide and rest during the day.
In addition, constant water temperature and PH value are very important for them, because they are actually very sensitive. Besides, they like houses with sand at the bottom.
Of course, filtration and water flow are also necessary, but the water flow is slow, maybe they like quiet. It is also important to choose the right partner for them. We can choose suitable playmates for them by considering factors such as body shape and habits. Of course, there may be unexpected situations. For example, little ones usually do them no harm, or just eat them as snacks. If his playmate is fierce, the little guy may put up with it for a while. If he can't stand it, he will fight with his opponent and fight to the death. The opponent is either dead or seriously injured. After all, the little guy is not easy to mess with.
Principle 2: Give the kids the right food. The little ones are carnivorous. They don't eat plants, and rarely eat all kinds of artificial feed. The above foods can't provide the nutrition needed for growth. Usually, frozen or fresh blood worms, earthworms, shrimps, shellfish, crabs, squid and snails are all their favorite foods. Be careful not to overfeed. If overfeeding may lead to constipation, they often pray for food, even if they are full, because they really like it. If their bellies become very big, it means that they have eaten too much. You can feed them 1-2 times a day.
Usually their stomachs deflate a few hours after eating. If their stomachs are always bulging, then your little guy may be constipated. Principle 3: always check the physical condition of the little guy. As a daily habit, carefully check the whole body of the little guy every day to see if there is any possibility of external diseases, bites and injuries caused by parasites and fungi.
By the way, observe their activities and see if there is anything unusual. One advantage of this routine check-up is that the little ones will get to know you soon. When you walk to the tanks, they will hover and swim up and down in front of you.
Pay attention to several bad signs: 1. He has a bad appetite. In fact, the little guy is greedy. If he is found to have a bad appetite or picky eaters, there must be something wrong.
2。 Press the line, if you find dark gray lines between the back and abdomen of the little guy, these lines can extend from the mouth to the tail, which is also an unwanted sign.
3。 For the type of white belly, if the little guy's stomach turns black and the color deepens, he should also pay attention.
4。 Under normal circumstances, the color of the little guy's back will change with the time of day and other factors, but if the color of his back gradually darkens and cannot change for a long time, it is a normal body color, which is also one of the danger signals.
If problems are found, carefully check the living environment of the little guy (salt temperature filtering PH, ammonia and nitrite concentration). If there is no problem in the environment, you should see that there is no other * * * (some big fish) in the little guy's tank to make him feel scared. And Tanqueray has enough hiding places for him to rest. If all the above conditions are normal, it is necessary to carefully check his body for physical damage. Cage culture of puffer fish has the advantages of maneuverability, flexibility, simplicity, wide adaptability in waters and simple operation.
One. The waters of cage culture should be sheltered from the wind and sunny, with quiet environment, fresh water, no pollutants and obstacles, wide water surface and good sunshine conditions.
The speed of waterway, dam front, sluice, main river and water exceeds 0 per second. 1 m water area is not suitable for setting cages.
The bottom of the cage should be 0. 5 meters high to prevent the cage from running aground.
Generally, the water with cages has a water depth of 3-6 meters all the year round, and the dissolved oxygen is more than 4 mg per liter. 2. When the puffer fish in the cage is about 3 cm long, the mesh of the cage is 6 meshes per square centimeter; When the size of puffer fish is more than 8 cm long, the mesh diameter is 1.
5 centimeters. The size of the cage is 5m * 8m *2.
5 meters, the upper mouth is 30 cm above the water. In relatively open waters, the arrangement of cages should be zigzag, plum blossom or herringbone, and the spacing between cages should be 15-30 meters; If the cages must be arranged in a straight line due to water conditions, every two cages should be grouped with an interval of more than 50 meters.
The area of the feeding cage generally accounts for about 4% of the set water surface. 3. Fish stocking 10- 15 Before fish stocking, the water in the cage should be tested.
It is required that the body surface of the fish species is complete, disease-free and injury-free, with strong physique and neat specifications. Before putting the puffer fish into the cage, put the oxygen bag with fry in the box for 15 minutes, and release the fish when the water temperature in the bag is almost the same as that in the box.
There are about 12 fish in the cage per square meter. In order to prevent a large number of moss growth in cages, a small number of fish feeding on plants should be kept in cages.
Fourth, feeding should be timed, fixed, qualitative and quantitative. There are some aquatic plants such as water peanuts in the cage, accounting for about 20% of the water surface.
1 One week before the puffer fish is released, the cage is sprinkled with soybean milk and bean dregs to cultivate the early bait of puffer fish. After the puffer fish is put into the box, it begins to feed the bait which is a mixture of minced fish meat and wheat flour according to the ratio of 3: 1, and the feeding amount is 10% of the fish weight.
The bait is placed on the dining table and fed twice at 9: 00 am and 4: 00 pm. V. Daily management Daily management mainly includes one attendance, two stresses and three defenses.
Check it if you are diligent. Check whether the net clothes are damaged before putting into the cage, check whether the box is box-shaped after putting into the cage, and clean the cage in time.
Check whether the cage is in good condition every morning, noon and evening. Always observe the situation of fish and water.
Second, grasp: First, grasp the timely washing of boxes. Cleaning cages usually use a box cleaner to clean the attachments on the net.
Care needs to be taken to avoid hurting the fish. Don't wash the cage often.
Second, grasp the timely transfer of boxes. According to the change of water regime and water quality, the container should be moved in time.
On the eve of the decline of cage position or in flood season, the cage must be moved to a suitable water level in time.
7. How to raise small puffer fish?
Feeding mode:
(1) The aquaculture mode and environmental aquaculture area require clean water quality, rich dissolved oxygen, no red tide, no pollutants and sewage inflow. Cage culture should choose a sheltered inner bay, the transparency is 7-8m, the flow velocity is 10cm/s, the optimum water temperature is 16-23℃, and the water temperature below 9℃ or above 28℃ is not conducive to its growth.
(2) fry weighing 3-4g are cultivated and grown, which can reach about 400g at the end of February and 1000g at the end of the next year. At this time, it can be harvested and listed. The best market specification of red fin oriental dolphin is 1kg, and the price is the highest. In order to achieve better culture effect, the weight of fish should reach more than 350 grams before wintering. Before 65438+February, the water temperature is still suitable for growth, so it is necessary to feed enough bait. In winter, when the fish can still eat, it is necessary to ensure a small amount of feeding as much as possible to prevent weight loss and ensure a stable survival rate. After overwintering, it began to return to normal growth in April. Especially in September-165438+1October when the water temperature is suitable, its growth is more rapid.
(3) Bait types and feeding methods: Mytilus mystus and striped mackerel are used in the juvenile stage, and striped mackerel, saury and striped mackerel are also used in the breeding stage besides sardines, mackerel and striped mackerel. In order to improve the quality of fish at harvest, squid, shrimp, oysters and clams are sometimes fed.