CATDOLL : CATDOLL: What are the key points of American rainbow trout farming technology?

What are the key points of American rainbow trout farming technology?

American rainbow trout is a cold-water fish belonging to the family Salmonidae. It is native to the Pacific coast of North America and is one of the four excellent freshwater aquaculture species promoted by the Food and Agriculture Organization of the United Nations to the world.

Rainbow trout has a small head, few bones, thick meat, no muscle spines, tender meat, delicious taste and no fishy smell. It is suitable for steaming, boiling, and grilling, and can also be eaten directly as sashimi.

According to relevant experts, rainbow trout should be raised like this:

1. Construction

The survival limit temperature of rainbow trout is 0 to 30 degrees, the growth water temperature is 5 to 22 degrees, and the optimal growth temperature is 12 to 18 degrees. The dissolved oxygen value is required to be maintained above 6 mg/L (should not be less than 5 mg/L), the suitable flow rate for life is 2-16 cm per second, and the pH value is 7-8. Rainbow trout grows fast, has high aquaculture yields, and has good economic benefits. It is especially suitable for high-density intensive water aquaculture in areas with abundant water, suitable water temperature, and rich dissolved oxygen. Mountain streams, groundwater, bottom water of newly built reservoirs, and cold spring water are all suitable. Generally, farms should build juvenile fish ponds and adult fish ponds. Juvenile fish ponds are generally circular, with an area of ​​10-30 square meters and a water depth of 20-40 cm. Adult fish ponds are generally 100-200 square meters, with a water depth of 70-90 cm. There should be a certain slope to use the natural drop of water to increase oxygen. Fish ponds should be of uniform standards, rectangular, and cement structure, which is conducive to feeding, management, and control of fish diseases, in line with the characteristics of rainbow trout that likes to go against the current. It is ideal if the fish pond is built against a mountain, and fish fences should be installed at the inlet and outlet.

2. Feeding and management

Before the juvenile fish grow to 10 grams or 15 grams, they are screened and 40% of the large fish are placed in the back half of the adult fish pond, and 60% of the small fish are placed in the front half of the adult fish pond, so that large and small fish are raised separately. The cement juvenile fish pond is cleaned with water once a day, and the cement adult fish pond is cleaned with water once every 5 days. The earthen pond is flushed with water that is exchanged 3 times per hour for 2 hours per week. At the drain outlet of the fish pond, the dissolved oxygen is lower than 3.5 mg/L. Increase the flow rate or mechanically increase oxygen to supplement the dissolved oxygen in the pond water. 3. Prevention and control of common fish diseases

Before the purchased eyed eggs are shipped, they must be bathed in 50ppm polyvinylpyrrolidone iodine (containing 1% available iodine) for 15 minutes. Oxygenation must be provided during the bath. The bath can kill the viruses on the eggs to prevent the IHN virus.

Symptoms of bacterial gill disease in juvenile fish: The body color of juvenile fish is dark, and they are weak in swimming at the drain or along the surface of the pond wall, and they lose their appetite. The number of dead fish increases day by day. There is mucus on the gills. When observed from the back, the gill cover is open. Treatment: Place the sick fish in a net and bathe them in 1/2000 copper sulfate solution for 1-2 minutes. Place the non-sick fish in the same pond in a net and bathe them in 1/2000 copper sulfate solution for 1 minute. Bath them in 1ppm furan solution for 1 hour. Feed sulfonamide bait. On the first day, add 200 mg of veterinary sulfonamide 6-methoxazole per kilogram of all bait used that day. The dosage for the 2nd to 4th day is 150 mg per kilogram of fish.

Symptoms of enteritis in juvenile fish: black fish body, red anus with mucus, purple intestine, no food or mucus in the intestine. Treatment: Feed with furazolidone bait, add 200 mg of veterinary furazolidone per kilogram of total feed on the first day, and add 150 mg of furazolidone per kilogram of fish on the 2nd to 4th day.

Third generation worms: Symptoms of ectoparasitic diseases such as Ichthyophthirius: They mostly occur in juvenile fish weighing less than 50 grams. Especially for juvenile fish weighing less than 5 grams, the water temperature is mostly 5-15 degrees during the onset period. The sick fish turn over and swim rapidly along the bottom or wall of the pond. In severe cases, they gather at the drain outlet, and the flow is weak. The number of dead fish increases. There are white spots on the body surface of Ichthyophthirius, and there is mucus on the gills. Treatment: Sprinkle formalin throughout the pond, make the pond water 1/2000 concentration and bathe for 10 minutes. Before applying the medicine, drain 50% of the pond water, block the drainage outlet, stop the flow of pond water, and then sprinkle the whole pond with the formalin solution prepared in advance. After 10 minutes of bathing, open it immediately and inject new water. This method can both cure and prevent diseases. During the high incidence period, bathe once every 10-15 days according to the same method.

You can go to some aquatic stations to check, for example, you can go and see if there is this

What freshwater fish is the most expensive?

Question 1: Which freshwater fish is the most expensive? That depends on your purpose. Do you buy it for eating, for viewing, or for understanding? I can provide a few references: American shad, mineral fish guppy, red dragon white sturgeon, Dali bowfish, giant salamander

Adopt it

Question 2: What is the most precious freshwater fish in China? 1. The price of giant salamander is more than 3,000 yuan per catty. 2. The price of Yangtze River knife fish is more than 2,000 yuan per catty. 3. The price of shad is more than 500 yuan per catty. 4. The price of wild Yangtze River pufferfish must be wild and more than 200 yuan per catty. The price of the fish must be alive to be worth the price. Dead fish is another matter. Haha, I hope you can adopt it.

Question 3: Which freshwater fish is the most expensive to breed and which freshwater fish is the most profitable to breed?

Rainbow trout lives at the junction of hot and cold weather. It requires high-tech breeding, but once the technology is mastered, it can dominate a market. It is truly a precious fish species.

Rainbow trout farming technology

1. Habits of rainbow trout

Rainbow trout is a cold-water fish. It likes to live in water bodies with clear water, gravel bottom, low water humidity, sufficient dissolved oxygen and abundant water flow. It is a carnivorous omnivorous fish with fierce feeding. The fry mainly feed on planktonic, benthic and aquatic animals. One-year-old fish begin to swallow small fish and amphibians. Adult fish feed on fish, etc. Under 14℃ conditions, it can reach 100-200 grams in one year, 400-1000 grams in two years, and life span is 8-11 years. The maximum body is 7.5 kg under captive conditions and can reach 25 kg in natural water bodies.

2. Rainbow trout farming

1. Parent fish breeding: water depth 1-1.5 meters, gravel bottom, water temperature 10-14℃, density 1-3 per square meter, male-female ratio 1:1. Change the water every day in the early stage of egg collection. Rainbow trout are afraid of light, so the light exposure is less than 12 hours a day. Feed vegetables in autumn and winter, animal feed accounts for 20%-30% of the total amount each year, plant feed accounts for 55%-70%, and some fresh small fish are fed before egg collection and sperm collection.

2. Artificial egg collection and fertilization: About one month before spawning, male broodstock can be seen fighting and chasing female fish. Female fish use their tail fins to dig pits and build nests in shallow water. Their body color gradually darkens, their cloaca is red and prominent, their abdomen is large, and they can feel free eggs when touched, which means they are mature. Male fish become black in color, have less mucus, have soft cloaca, and white liquid flows out when the belly is lightly pressed. Stop feeding three days before egg collection. Collect eggs first and then collect liquid. After collecting eggs, rinse with isotonic solution, squeeze out liquid, stir gently with feathers for half a minute, add a small amount of fresh water, let the eggs fully fertilize, stir slightly, add more fresh water, rinse excessive liquid, add more fresh water, and let it stand for 30 to 60 minutes before the eggs absorb water and become elastic. After fertilization, pour into the hatching tray for incubation. Avoid vibration during the period, and all operations are carried out under light-shielding conditions.

3. Raising rainbow trout

1. Breeding farm: It must have ponds for fry, fry, fingerlings, adult fish and broodstock. Except for broodstock ponds which should be made of earth, cement ponds are preferred for other ponds.

2. Feeding and management: The key lies in dissolved oxygen, water temperature and feed. The dissolved oxygen should be above 6.4 mg/L and the water temperature should be 10-18℃. The newly hatched fish mainly absorb egg yolk. After 20 days, they start to eat by sprinkling broad bean milk on the upper reaches of the pond. They should eat small meals frequently. Two months after the start of feeding, crush the animal bones and liver and mix with a small amount of bean cake powder to feed. At the end of the year, it is the fingerling stage, when the fish eat more and grow fastest. In the second year, it is the adult stage, and commercial feed is mainly used. In addition, the stocking density and water inflow and outflow should be adjusted according to the size of the fish.

IV. Prevention and treatment of common diseases

1. Saprolegniasis: It occurs during the hatching period of fish eggs. Saprolegniasis grows on dead eggs, and the hyphae surround and infect healthy eggs. After 20 hours, the eggs suffocate and die.

2. Microcariasis: It is a common parasitic disease, and many small white spots can be seen on the body of sick fish.

3. Trichodiniasis: It parasitizes on the skin and gills and causes diseased fish to have difficulty breathing, gather at the bottom of the pond, and move slowly.

4. Trichodina disease: This disease attacks the skin and fins of fish species. Sick fish become extremely restless and struggle desperately from time to time.

5. Enteritis: Adult fish are prone to this disease. The intestines become inflamed, congested, red and swollen, and yellow mucus flows out when the abdomen is pressed lightly.

The main prevention and treatment methods for the above diseases are:

(1) Regularly disinfect and wash the infected body, mainly using low-solubility solutions such as mercuric nitrate, malachite green, copper sulfate, etc., or using salt water, which can also separate dead eggs and bacteria.

(2) Strengthen the cleaning and disinfection of bait and feeding tools, and strictly avoid feeding spoiled feed. Feed more vitamins, especially vitamin E, and strengthen treatment combined with improved environment to prevent weakness and death.

Question 4: What is the most expensive freshwater fish in the world? The most expensive fish in the world

A special "blood red dragon" fish that won the championship in the "2004 Singapore International Fish Show" was bought by a Japanese customer for US$600,000 (equivalent to nearly RMB 5 million).

Lin Guoyao, the head of a Singapore aquarium company, told local media: "After more than four years of careful cultivation, this special blood red dragon has grown to a fully mature stage. Whether in terms of overall shape or color, it has shown its best appearance. The red and purple colors complement each other, and it can be said to have truly reached the highest level of the so-called riot of colour. The most important point is that its head is tilted upwards, fully demonstrating its arrogant kingly demeanor."

It is reported that the most expensive ornamental fish in the Singapore market is the dragon fish. In 2001, at the World Fish Show held in Singapore, a "purple blood-red dragon" won the championship in the dragon fish category. At that time, the dragon fish, which was 4 and a half years old, 55 cm long and weighed 2 kg, was bought for 88,888 Singapore dollars (equivalent to more than 400,000 RMB). Dragon fish are divided into three varieties: golden dragon fish, red dragon fish and green dragon fish.

The dragon is the most beloved and worshipped deity of the Chinese. It represents auspiciousness and nobility, and the arowana also symbolizes nobility, auspiciousness, and wealth. Arowana with high-quality bloodlines has always been an important pet in the feng shui tank of upper-class families. Therefore, arowana has always been the favorite of ornamental fish breeders. "Blood red dragon" is a type of red arowana, and "blood red dragon" is a title. Lin Yijian, the head of the sales department of Singapore Qianhu Fishery, said: "Red dragon is the supreme fish in the arowana family; like Mercedes-Benz among car brands, it is a symbol of noble quality." There is a kind of red arowana bred by Qianhu Fish Farm called "No. 1 Red Dragon" and another called "Purple Red Dragon". The latter is of better quality. In addition to a layer of red, the fish body also has a light purple-blue color. According to industry insiders, generally speaking, the price of arowana can range from a few thousand Singapore dollars to 200,000 Singapore dollars, depending on the size and quality of the arowana.

Question 5: What is the most expensive freshwater fish? The Chinese sturgeon. Of course, this is a first-class protected animal in China. You can’t buy it even if you want to.

Question 6: Which freshwater fish in China is the most expensive?

Question 7: What is the most expensive freshwater fish now? Betta

Question 8: What is the most expensive freshwater fish? Wild Songjiang perch is in short supply; wild shad is also extremely expensive. Among ornamental fish, golden dragonfish is also very expensive.

Question 9: What is the most expensive freshwater fish to breed? The most expensive freshwater fish now is betta fish.

Question 10: Which freshwater fish is the most expensive? That depends on your purpose. Do you buy it for eating, for viewing, or for understanding? I can provide a few references: American shad, mineral fish guppy, red dragon white sturgeon, Dali bowfish, giant salamander

Adopt it