Koi is a kind of precious ornamental fish that has been artificially bred from the mutant strain of salmon. Its elegant posture, beautiful shape, bright colors, brilliant stripes, and high ornamental value are popular among people. The market is optimistic and breeding. Tendency to heat is currently a major species that can be earned in the European market for the ornamental fish breeding industry. Its breeding techniques are as follows:
First, aquaculture environment is selected for ventilation, sunny, adequate water flow, drainage and irrigation facilities to build a pool. The broodstock area is 30--40 square meters, the pool depth is 1.5-2 meters, and the water depth is 1.2--1.5 meters. Spawning pool 15-20 m2, pool depth 1.5m, depth 1-1.2m. The hatchery pool is 3--5 square meters, the pool depth is 0.8--1m, and the water depth is 0.6--0.8m. Seed pool 10-15 square meters, pool depth 0.5--0.6m, water depth 0.4m. The size of adult fishpond depends on the amount of feeding, generally 2000-3300 square meters is appropriate, not only easy to manage, the water quality is also relatively stable, pool depth 1.5--2m, water depth of about 1.5m.
Koi is more adaptable to the environment, but it cannot resist the rapid changes in water temperature. The temperature difference cannot exceed 2 - 3°C. A sudden drop or rise in water temperature is likely to lead to illness. The water temperature of the most suitable living of Koi is 20--25°C. In this water temperature, Koi swims actively, has a strong appetite, and is physically strong and colorful. Koi carp is suitable for living in a slightly alkaline, low hardness water quality environment, with spring water as the best, it contains a variety of mineral elements and other components, can increase the fish body pigment, make Koi body color more vivid, and soluble Oxygen is sufficient.
Second, reproductive technology Broodstock selection is one of the key measures for breeding Koi. Select healthy fish, pure lineages, clear varietal characteristics, clean and clear color margins, smooth and tidy scales, stable swim posture, complete fins, well-proportioned, non-damaging, disease-free fish as a parent. At the same time, females are required to be over 4 years of age, males above 3 years of age, and weighing over 1.5 kg. The choice of such a broodstock resulted in good reproductive gonad development, high viability of the egg and sperm, and high fertility and hatchability. The reproduction time of Koi is similar to that of ordinary squid. It is usually from April to May each year. When the water temperature is stable above 16°C, the female and male koi can be singled out in a ratio of 1:2 to 3. In the spawning pool, a pre-sterilized fish nest is placed in the spawning pond so that it can spawn on its own. After the spawning is over, the broodstock is picked up, the fish nest is transferred to the hatching pond for hatching, and the fry can be incubated after being hatched for 5-7 days. The cultivation method is similar to that of the common bream.
Third, feed feeding is currently used in the breeding process using artificial pellet feed for feeding. Crude protein content in feed is above 35%. Adopt domestication method when feeding, make the koi form the habit of focusing on grab food. According to the specifications of the fish body, timely replacement of feed with a suitable particle size (see Table 1). Feeding 2 times a day, the daily feeding amount is about 2% - 10% of the total weight of the fish. The specific amount of feeding also depends on the status of the fish, the size of the fish, and the water temperature. When the fish body size is specified, the lower the water temperature, the lower the daily feeding rate, and the higher the water temperature, the higher the daily feeding rate. When the water temperature is constant, the larger the fish body size, the lower the daily feeding rate, and the smaller the fish body size, the higher the daily feeding rate. Every time the amount of feed is controlled, it is appropriate to let the fish eat 80%.
Table 1: Feed particle size for different fish size selection Fish tail weight/g Feed particle size/mm
30--100 1.5
100--200 2
>200 2.4
IV. Water quality control Maintaining good water quality is an important factor in ensuring the healthy growth of Koi fish. Therefore, the water quality of the fish pond should be refreshing. It is necessary to adhere to the cleanup and regular water changes. The leftover bait residue should be removed from the pool on a daily basis to keep the water surface clean. There are floating objects and pollutants. In summer, when the water temperature is high, the water should be replaced once every 5-7d, and in spring and autumn, the water should be replaced once every 10-15d, and the amount of water changed is about 1/3 of the original pool. To maintain the transparency of the pool water at 30--40cm, the transparency is too high, the fish is easy to be scared; the transparency is too low, it is not easy to see the Koi's feeding and activities, and it is not easy to observe the pool.
In order to increase the oxygen level in time, the dissolved oxygen in the pool water should always be kept above 5 mg/L in order to maintain the vigorous feeding state and rapid growth rate of the carp. The method of applying quicklime is used to adjust the pH value of the pool water. Generally, quicklime is applied once a month, and the whole pool is used for sprinkling, so that the lime water content in the pool water can be 30 mg/L each time.
V. Prevention of Fish Diseases When the water temperature is 15°C, use a "water mold net" Quanchiposa 1 time to make the pool water content 0.15mg/L to prevent fungal diseases (such as hydromycosis, etc.); when the water temperature is 20°C With copper sulfate and ferrous sulfate mixture (mass ratio 5:2) Quanchiposa once, so that the pool water content of 0.7mg / L, to prevent small parasites on the parasite (such as trichoderma, oblique tuberculosis) disease Occurrence; When the water temperature is 20-25 °C, use 90% crystal trichlorfon Quanchiposa 1, so that the pool water content of 0.5mg / L, to prevent other parasites (such as fish carp, anchor carp) disease Occurrence; When the water temperature is 25--30°C, it is disinfected once a month with “chloricidal killing king†so that the content in the pool water is 0.5mg/L to prevent the occurrence of bacterial diseases such as erythroderma.
Sixth, daily management must first adhere to the tour pond to prevent flooding. Second, we must fill water regularly to maintain the water level. In summer, the pool water is continuously evaporating due to the sun's radiation, and the water level will gradually decrease. Therefore, new water must be constantly added to keep the water level during feeding. Maintaining a deeper water level during the winter will benefit the safe wintering of Koi.
First, aquaculture environment is selected for ventilation, sunny, adequate water flow, drainage and irrigation facilities to build a pool. The broodstock area is 30--40 square meters, the pool depth is 1.5-2 meters, and the water depth is 1.2--1.5 meters. Spawning pool 15-20 m2, pool depth 1.5m, depth 1-1.2m. The hatchery pool is 3--5 square meters, the pool depth is 0.8--1m, and the water depth is 0.6--0.8m. Seed pool 10-15 square meters, pool depth 0.5--0.6m, water depth 0.4m. The size of adult fishpond depends on the amount of feeding, generally 2000-3300 square meters is appropriate, not only easy to manage, the water quality is also relatively stable, pool depth 1.5--2m, water depth of about 1.5m.
Koi is more adaptable to the environment, but it cannot resist the rapid changes in water temperature. The temperature difference cannot exceed 2 - 3°C. A sudden drop or rise in water temperature is likely to lead to illness. The water temperature of the most suitable living of Koi is 20--25°C. In this water temperature, Koi swims actively, has a strong appetite, and is physically strong and colorful. Koi carp is suitable for living in a slightly alkaline, low hardness water quality environment, with spring water as the best, it contains a variety of mineral elements and other components, can increase the fish body pigment, make Koi body color more vivid, and soluble Oxygen is sufficient.
Second, reproductive technology Broodstock selection is one of the key measures for breeding Koi. Select healthy fish, pure lineages, clear varietal characteristics, clean and clear color margins, smooth and tidy scales, stable swim posture, complete fins, well-proportioned, non-damaging, disease-free fish as a parent. At the same time, females are required to be over 4 years of age, males above 3 years of age, and weighing over 1.5 kg. The choice of such a broodstock resulted in good reproductive gonad development, high viability of the egg and sperm, and high fertility and hatchability. The reproduction time of Koi is similar to that of ordinary squid. It is usually from April to May each year. When the water temperature is stable above 16°C, the female and male koi can be singled out in a ratio of 1:2 to 3. In the spawning pool, a pre-sterilized fish nest is placed in the spawning pond so that it can spawn on its own. After the spawning is over, the broodstock is picked up, the fish nest is transferred to the hatching pond for hatching, and the fry can be incubated after being hatched for 5-7 days. The cultivation method is similar to that of the common bream.
Third, feed feeding is currently used in the breeding process using artificial pellet feed for feeding. Crude protein content in feed is above 35%. Adopt domestication method when feeding, make the koi form the habit of focusing on grab food. According to the specifications of the fish body, timely replacement of feed with a suitable particle size (see Table 1). Feeding 2 times a day, the daily feeding amount is about 2% - 10% of the total weight of the fish. The specific amount of feeding also depends on the status of the fish, the size of the fish, and the water temperature. When the fish body size is specified, the lower the water temperature, the lower the daily feeding rate, and the higher the water temperature, the higher the daily feeding rate. When the water temperature is constant, the larger the fish body size, the lower the daily feeding rate, and the smaller the fish body size, the higher the daily feeding rate. Every time the amount of feed is controlled, it is appropriate to let the fish eat 80%.
Table 1: Feed particle size for different fish size selection Fish tail weight/g Feed particle size/mm
30--100 1.5
100--200 2
>200 2.4
IV. Water quality control Maintaining good water quality is an important factor in ensuring the healthy growth of Koi fish. Therefore, the water quality of the fish pond should be refreshing. It is necessary to adhere to the cleanup and regular water changes. The leftover bait residue should be removed from the pool on a daily basis to keep the water surface clean. There are floating objects and pollutants. In summer, when the water temperature is high, the water should be replaced once every 5-7d, and in spring and autumn, the water should be replaced once every 10-15d, and the amount of water changed is about 1/3 of the original pool. To maintain the transparency of the pool water at 30--40cm, the transparency is too high, the fish is easy to be scared; the transparency is too low, it is not easy to see the Koi's feeding and activities, and it is not easy to observe the pool.
In order to increase the oxygen level in time, the dissolved oxygen in the pool water should always be kept above 5 mg/L in order to maintain the vigorous feeding state and rapid growth rate of the carp. The method of applying quicklime is used to adjust the pH value of the pool water. Generally, quicklime is applied once a month, and the whole pool is used for sprinkling, so that the lime water content in the pool water can be 30 mg/L each time.
V. Prevention of Fish Diseases When the water temperature is 15°C, use a "water mold net" Quanchiposa 1 time to make the pool water content 0.15mg/L to prevent fungal diseases (such as hydromycosis, etc.); when the water temperature is 20°C With copper sulfate and ferrous sulfate mixture (mass ratio 5:2) Quanchiposa once, so that the pool water content of 0.7mg / L, to prevent small parasites on the parasite (such as trichoderma, oblique tuberculosis) disease Occurrence; When the water temperature is 20-25 °C, use 90% crystal trichlorfon Quanchiposa 1, so that the pool water content of 0.5mg / L, to prevent other parasites (such as fish carp, anchor carp) disease Occurrence; When the water temperature is 25--30°C, it is disinfected once a month with “chloricidal killing king†so that the content in the pool water is 0.5mg/L to prevent the occurrence of bacterial diseases such as erythroderma.
Sixth, daily management must first adhere to the tour pond to prevent flooding. Second, we must fill water regularly to maintain the water level. In summer, the pool water is continuously evaporating due to the sun's radiation, and the water level will gradually decrease. Therefore, new water must be constantly added to keep the water level during feeding. Maintaining a deeper water level during the winter will benefit the safe wintering of Koi.