Australian gems, or gems, are Australia's prestigious freshwater fishes. China has introduced aquaculture in recent years. The gemstone has beautiful appearance, mild temperament, strong disease resistance, rapid growth and delicious taste. At present, the market price of commercial fish is 80-90 yuan per kilogram, which is still in short supply, and the aquaculture efficiency is 5 to 6 times that of conventional fish. The market prospect is very promising. Now we introduce the geminal efficient intensive culture technology as follows:
First, seedling cultivation selection area 1.5 acres ~ 3 acres, depth of 1.5 meters ponds, require the bottom flat, thick mud about 10 cm, into the drainage is convenient, the water is fresh and pollution-free, pH 6.8 to 7.5, dissolved oxygen 4.5 mg / l or more. Ponds are protected with concrete slabs around the pond, and each pool is equipped with a pump. In the 15 days prior to the stocking of the gems, 15 kg of quick lime per acre was used to dry clear ponds, killing enemy organisms and pathogens in the pond. Seven days before stocking, 350 kg of organic fertilizer fermented and fermented were placed per acre of water, followed by 0.6 meter of water. When filling the water, the water inlet is filtered with a 60-mesh sieve to prevent the entry of harmful organisms into the pool. A few days later, the breeding of clams, copepods, rotifers, and otters in the pond reached a peak, and this is the best time to put summer fry. Generally, in mid-and late-May, fish fry are released when the pond water temperature reaches 20°C. Fry specifications are about 2.5 cm in length. When stocking, the fry is first sterilized in a bowl containing 5% salt water for 10 minutes, and then the fish can be poured into the cultivating pool. The amount of 2500 to 3000 tails per acre is appropriate.
Three days after the fry began to feed, the juveniles were fed first, and 80,000 catfish seedlings with a body length of 1.2 centimeters per day were placed per mu. When the fry grows to more than 5 cm, it begins to tame. The method is to first stop casting the eel fry for 2 days, and on the third day, start feeding the fresh minced fish. The method of throwing and domesticating should be adopted, firstly feeding in small amounts, and then gradually increasing the amount of feeding. After 4 days to 5 days, it can be fully adapted. Feed 2 times a day, and vote for 3/5 of the day's volume from 7 am to 8 am and 2/5 from 4 pm to 5 pm. The daily feeding amount was 8% to 12% of the body weight of the fish. Summer fish fry should be shallow underwater pool, on the one hand, can increase the density of the bait in the unit of water in the pond, which is conducive to the feeding of fry; on the other hand, it can increase the temperature of water and promote the growth of fry. With the rapid growth of fry, the pool water is gradually deepened, and the water depth is added to 1.5 meters after 14 days. Change the water once every 7 days, changing the water volume from 1/5 to 1/6 of the pool water each time. Each morning, mid-night and evening patrols were conducted 3 times to observe fish feeding, activities, growth and pond water quality changes. 1 to 2 o'clock in the afternoon, the water pump is used to increase oxygen for 1.5 hours, and the dissolved oxygen and pH value are measured regularly so that the feeding amount can be adjusted timely and the prevention of fish diseases can be done properly. Breeding practice has proved that after 30 days of careful cultivation, the size of the gem seedlings can reach 9.5 cm in length. In this case, the fry should be promptly transferred to the adult fish breeding pond (box) and transferred into the adult fish culture.
Second, into the fish cage intensive
1. Water selection According to the habits of gemstones, select cages with a water depth of more than 3 meters and a flow rate of 0.02 m/sec to 0.2 m/sec, such as the bays, lakes, rivers, or outboards. Requires avoidance of the main channel, quiet environment, small waves, clean water, and no pollution.
2. There are many ways to place cages in cages. Generally, the work pontoon is centered, and cages are placed on both sides. This makes operation and management more convenient. The volume of the cage is generally 4m 4m 2.5m or 5m 4m 2.5m. The cage is an open, double-layered structure with a knotless polyethylene cage on the inside, 2 cm around the mesh, 1 cm on the bottom mesh, a 3 m 3 m polyethylene protection box on the outside, and a mesh of 3 cm. The cage is framed with angle steel and iron pieces, and the old oil barrel is used as a floater. When the cage is placed, the cage should be opened vertically and naturally. The cage should be put into water 10 days before the fish is released. The tank should be immersed in the water for 2 meters. The top of the cage should be 0.5 meters above the water surface. When the box is in contact with the water surface, use a polyethylene net cloth fence with a height of 40 cm and a size of 10 mesh. The net cloth should be 10 cm above the water surface to prevent the artificial floating food from floating out of the box, causing waste. The cages are usually placed 5 to 10 meters from the shore and fixed with steel ropes or polyethylene ropes.
3. Fish species stocking Choose large-sized fish species with robust physique, lively swimming, neat specifications, and no disease or injury. Stocking densities range from 30 to 40 per square meter. According to the characteristics that gems and catfish species are sensitive to the change of water temperature, the temperature difference should not exceed 2°C when the fish species enter the box. Before entering the box, apply 1.5% to 2% saline to disinfect fish for 7 minutes to 8 minutes.
4. Feed feed requirements for the buoyant full price with granular materials, and high protein content, rich nutrition, good palatability. The crude protein content of feed is required to be 35% to 40%. When feeding, the first one-week feeding and domestication should be performed, that is, first hit the feed barrel or pot, so that it forms a conditional reflex. Domestication is performed twice a day, usually at 7 am to 8 am and from 16 am to 17 am. Feeding rate and feeding amount are grasped according to the "slow-fast-slow" rhythm and the "less-more-less" principle. Feeding amount should be flexibly controlled according to the water temperature, fish species specifications and actual feeding conditions. When the water temperature is 18°C ​​to 20°C, the feeding amount is 2% to 2.5% of the body weight of the fish, and when the temperature is 21°C to 35°C, it is 3% to 7% of the body weight of the fish. A food table can be built in the cage to allow it to hang at a depth of 1 meter. Operators can stand and feed at a fixed position on the working pontoon.
5. Day-to-day management requires four diligence and four defenses. The four are: ground patrols, diligent inspections, ground scrubbing nets, and ground maintenance cages. Ground patrol means that you should pay attention to the patrol pond so that problems can be found and dealt with in a timely manner. Diligent inspection means checking whether the nets of the cage are unblocked or damaged. The scrubbing of the nets can prevent the attached sediment, excessive algae, and the mesh from being blocked. Water exchange; maintenance, that is, to maintain the stability of the box, the tether is strong, the box is intact. The four defenses are: prevent caisson from escaping fish, prevent man-made damage, prevent winds from turning over, and prevent pesticide contamination. In addition, as the water level rises and falls, the cage needs to be adjusted to a suitable depth. In addition, due to the rapid growth of gems in gems and cages, after a period of breeding, there will be differences in specifications between individuals, and they should be cultured in a timely manner in order to avoid polarization and be conducive to high yields.
6. Fish disease prevention and control of fish diseases should adhere to the principle of "prevention and health management." Fish stocking and application of 1.5% to 2% of salt or 0.4ppm of dibromohydantoin, etc. into the tank after each stocking, and using 15ppm of quicklime and 0.3ppm in the cage every 20 days or so Disodium bromide disinfection. Intestinal septicemia is a common disease of gem gills. All kinds of fish are susceptible to infection. It can take 180 g of oxytetracycline per 100 kg of feed and continue feeding for 7 days to 10 days. In addition, the small melon worm is also a common disease of Australian gem worms. The disease is caused by the skin and pupa tissues of the small melon parasitized fish body. The fish body can be soaked with 8 g/L copper sulfate for 15 minutes to 20 minutes.
First, seedling cultivation selection area 1.5 acres ~ 3 acres, depth of 1.5 meters ponds, require the bottom flat, thick mud about 10 cm, into the drainage is convenient, the water is fresh and pollution-free, pH 6.8 to 7.5, dissolved oxygen 4.5 mg / l or more. Ponds are protected with concrete slabs around the pond, and each pool is equipped with a pump. In the 15 days prior to the stocking of the gems, 15 kg of quick lime per acre was used to dry clear ponds, killing enemy organisms and pathogens in the pond. Seven days before stocking, 350 kg of organic fertilizer fermented and fermented were placed per acre of water, followed by 0.6 meter of water. When filling the water, the water inlet is filtered with a 60-mesh sieve to prevent the entry of harmful organisms into the pool. A few days later, the breeding of clams, copepods, rotifers, and otters in the pond reached a peak, and this is the best time to put summer fry. Generally, in mid-and late-May, fish fry are released when the pond water temperature reaches 20°C. Fry specifications are about 2.5 cm in length. When stocking, the fry is first sterilized in a bowl containing 5% salt water for 10 minutes, and then the fish can be poured into the cultivating pool. The amount of 2500 to 3000 tails per acre is appropriate.
Three days after the fry began to feed, the juveniles were fed first, and 80,000 catfish seedlings with a body length of 1.2 centimeters per day were placed per mu. When the fry grows to more than 5 cm, it begins to tame. The method is to first stop casting the eel fry for 2 days, and on the third day, start feeding the fresh minced fish. The method of throwing and domesticating should be adopted, firstly feeding in small amounts, and then gradually increasing the amount of feeding. After 4 days to 5 days, it can be fully adapted. Feed 2 times a day, and vote for 3/5 of the day's volume from 7 am to 8 am and 2/5 from 4 pm to 5 pm. The daily feeding amount was 8% to 12% of the body weight of the fish. Summer fish fry should be shallow underwater pool, on the one hand, can increase the density of the bait in the unit of water in the pond, which is conducive to the feeding of fry; on the other hand, it can increase the temperature of water and promote the growth of fry. With the rapid growth of fry, the pool water is gradually deepened, and the water depth is added to 1.5 meters after 14 days. Change the water once every 7 days, changing the water volume from 1/5 to 1/6 of the pool water each time. Each morning, mid-night and evening patrols were conducted 3 times to observe fish feeding, activities, growth and pond water quality changes. 1 to 2 o'clock in the afternoon, the water pump is used to increase oxygen for 1.5 hours, and the dissolved oxygen and pH value are measured regularly so that the feeding amount can be adjusted timely and the prevention of fish diseases can be done properly. Breeding practice has proved that after 30 days of careful cultivation, the size of the gem seedlings can reach 9.5 cm in length. In this case, the fry should be promptly transferred to the adult fish breeding pond (box) and transferred into the adult fish culture.
Second, into the fish cage intensive
1. Water selection According to the habits of gemstones, select cages with a water depth of more than 3 meters and a flow rate of 0.02 m/sec to 0.2 m/sec, such as the bays, lakes, rivers, or outboards. Requires avoidance of the main channel, quiet environment, small waves, clean water, and no pollution.
2. There are many ways to place cages in cages. Generally, the work pontoon is centered, and cages are placed on both sides. This makes operation and management more convenient. The volume of the cage is generally 4m 4m 2.5m or 5m 4m 2.5m. The cage is an open, double-layered structure with a knotless polyethylene cage on the inside, 2 cm around the mesh, 1 cm on the bottom mesh, a 3 m 3 m polyethylene protection box on the outside, and a mesh of 3 cm. The cage is framed with angle steel and iron pieces, and the old oil barrel is used as a floater. When the cage is placed, the cage should be opened vertically and naturally. The cage should be put into water 10 days before the fish is released. The tank should be immersed in the water for 2 meters. The top of the cage should be 0.5 meters above the water surface. When the box is in contact with the water surface, use a polyethylene net cloth fence with a height of 40 cm and a size of 10 mesh. The net cloth should be 10 cm above the water surface to prevent the artificial floating food from floating out of the box, causing waste. The cages are usually placed 5 to 10 meters from the shore and fixed with steel ropes or polyethylene ropes.
3. Fish species stocking Choose large-sized fish species with robust physique, lively swimming, neat specifications, and no disease or injury. Stocking densities range from 30 to 40 per square meter. According to the characteristics that gems and catfish species are sensitive to the change of water temperature, the temperature difference should not exceed 2°C when the fish species enter the box. Before entering the box, apply 1.5% to 2% saline to disinfect fish for 7 minutes to 8 minutes.
4. Feed feed requirements for the buoyant full price with granular materials, and high protein content, rich nutrition, good palatability. The crude protein content of feed is required to be 35% to 40%. When feeding, the first one-week feeding and domestication should be performed, that is, first hit the feed barrel or pot, so that it forms a conditional reflex. Domestication is performed twice a day, usually at 7 am to 8 am and from 16 am to 17 am. Feeding rate and feeding amount are grasped according to the "slow-fast-slow" rhythm and the "less-more-less" principle. Feeding amount should be flexibly controlled according to the water temperature, fish species specifications and actual feeding conditions. When the water temperature is 18°C ​​to 20°C, the feeding amount is 2% to 2.5% of the body weight of the fish, and when the temperature is 21°C to 35°C, it is 3% to 7% of the body weight of the fish. A food table can be built in the cage to allow it to hang at a depth of 1 meter. Operators can stand and feed at a fixed position on the working pontoon.
5. Day-to-day management requires four diligence and four defenses. The four are: ground patrols, diligent inspections, ground scrubbing nets, and ground maintenance cages. Ground patrol means that you should pay attention to the patrol pond so that problems can be found and dealt with in a timely manner. Diligent inspection means checking whether the nets of the cage are unblocked or damaged. The scrubbing of the nets can prevent the attached sediment, excessive algae, and the mesh from being blocked. Water exchange; maintenance, that is, to maintain the stability of the box, the tether is strong, the box is intact. The four defenses are: prevent caisson from escaping fish, prevent man-made damage, prevent winds from turning over, and prevent pesticide contamination. In addition, as the water level rises and falls, the cage needs to be adjusted to a suitable depth. In addition, due to the rapid growth of gems in gems and cages, after a period of breeding, there will be differences in specifications between individuals, and they should be cultured in a timely manner in order to avoid polarization and be conducive to high yields.
6. Fish disease prevention and control of fish diseases should adhere to the principle of "prevention and health management." Fish stocking and application of 1.5% to 2% of salt or 0.4ppm of dibromohydantoin, etc. into the tank after each stocking, and using 15ppm of quicklime and 0.3ppm in the cage every 20 days or so Disodium bromide disinfection. Intestinal septicemia is a common disease of gem gills. All kinds of fish are susceptible to infection. It can take 180 g of oxytetracycline per 100 kg of feed and continue feeding for 7 days to 10 days. In addition, the small melon worm is also a common disease of Australian gem worms. The disease is caused by the skin and pupa tissues of the small melon parasitized fish body. The fish body can be soaked with 8 g/L copper sulfate for 15 minutes to 20 minutes.