Due to the lower water temperature in winter ponds, fish eat less, and their growth rate is also slow. This often causes people an illusion that fish “cultivate†winter, and people “cultivate†winter, relaxing management. As a result, the fry survival rate was low when the fry was sold the following year. So, how can we improve the survival rate of fry? Now introduce its winter management technology.
Preparation before winter
1. Clearing ponds should be prepared before and after October of each year for disinfection of winter fry. The size of overwintering area should be selected based on actual conditions. Back-to-north direction should be selected as far as possible. Drainage and irrigation should be convenient, with an area of ​​over 1 mu, and the water depth should be maintained at 80 cm or more. Prepare stocking ponds for wintering seedlings. Disinfect the ponds thoroughly before putting the fishes. It is best to dry in water for one week and handle more than 15 centimeters thick mud (rinse with a mud-pumping machine or running water or discharge them out of the pond). .
Clearing ponds in the wintering ponds are also disinfected with the same fry before other seasons. Lime, tea bran or strong chlorine (bleaching powder) can be used for spilling. It is mainly to kill viral bacteria, miscellaneous fish and other natural enemies. Usage and dosage are shown in Table 1 (slightly).
Note: Tea bran should be crushed, soaked for 2-3 days, then boiled with boiling water, and then stir well, even the scum with Quanchiposa juice. Lime and strong chlorine powder (bleached powder) splashed in the whole pool after being mixed with water.
2. Preparation of fish species Stocking species for overwintering fry should be adapted to local conditions to suit their pond conditions and market needs. If the pond water temperature is maintained above 12°C and the water depth is maintained at more than 1.5 meters, consider warm water fish such as wild pheasants, earthworms and tilapia. If you don’t have safe wintering in stocking salmon in previous years, warm water fish need not be considered. Under normal circumstances, the average water depth is more than 1.2 meters per acre of water, and conventional stocking for wintering fry can refer to Table 2 (abbreviated).
Daily management
The daily management of wintering fry is first of all water quality management. In winter, the water temperature is lower, the fish eat less, the metabolites are less, the plankton is naturally reduced, and the transparency of the pool water is relatively high, which is not conducive to overwintering and growth of fish. Therefore, winter ponds are generally placed on the edge of ponds with pigs, ducks, chicken manure, or rice stalks after stacking, so that the water quality of ponds is refreshing, with a green bean color, and the transparency is maintained at about 20 cm. This will not only save feed costs, but also improve the survival rate of fry. Secondly, for feed feeding, when the water temperature is above 20°C, feed green feed (such as Sudan grass, ryegrass, oil cane, etc.) and concentrate feed (such as peanut bran, pellet feed, and grain sprouts) on a daily basis. . Generally, the daily amount of green feed accounts for about 6%-8% of the fish's body weight, and it is fed in the morning. The concentrate feed accounts for about 2%-3% of the fish's body weight. When the water temperature is lower than 15°C, no further feed is required. However, it should be noted whether there is any leakage in the pond and prevent the hypoxia or freezing of fry in the pond. Once again, the proper supplementation of new water, overwintering the pond for a period of time, will result in deterioration of the water quality. Therefore, if the conditions permit, on a sunny day, proper injection of fresh water will greatly benefit the growth and development of the fish.
Disease prevention and treatment
Most wintering fry are susceptible to bacterial gill disease at the beginning of winter, fish diseases caused by parasites before the beginning of spring, water blight at 15°C-25°C, or brucellosis after scraping fish.
1. Preventive measures: 1 Be careful to minimize fish injuries. 2 When the number of fry is too large, dip the fish fry for 10-15 minutes with 0.5%-0.6% saline or dip the fish with 0.1g of potassium permanganate solution per cubic meter for 5-10 minutes, and then put it again. pond. 3 Every 20-30 days, splash the limestone Quanchipi once, and use 15-20 kg per mu for 1 meter deep, splashing water at Quanchipi. 4 with tea bran (whole, should not break) per acre surface, a depth of 1 meter with 7-8 kg, placed in the middle of the pond and the middle, let it slowly dissolve, from the role of disinfection and regulation of water quality.
2, treatment: 1 bacterial gill disease. Symptoms: The diseased fish has a dark body color and travels alone. The lids are opened. There are many mucus on the silk, and some decay into a "open skylight" shape. This is a typical bacterial gill disease. At this time, the pond water body can be disinfected with quicklime (method is the same as preventive measure 3), and the next day with half a catty of trichlorfon (crystals) plus 2 coarse salty water, Quanchiposa (1 meter deep per acre), meanwhile The compound fish drug was fed continuously for 3-6 days. 2 small melon worm disease. Popular in water temperature 15 °C -25 °C, the symptoms: sick fish swim slowly, floating on the water, sometimes the cluster around the pool, check the sick fish fish, fins, chin, there are many small white spots. At this time, 1 meter of water per acre can be used half a catty of dry chili and 2 pieces of dried ginger, boiled with 4 pounds of water and boiled for half an hour. Then even the scum with a splash of Quanchipa, for 2 consecutive days, once a day, can be expected Effect. 3 Other fish diseases caused by parasites. Mainly in the late winter and early spring, larger individual fish fry, caused by poor water quality, such as trichomonads, hidden whipworm, pupa tuberculosis and other diseases, then can use buckwheat leaves and leaves water, every 40 kg of water per 667 cubic meters of water tied into The piled up near the inlet can achieve the purpose of prevention. It can also use copper sulphate and ferrous sulphate mixture. Each cubic metre of water is splashed with 0.5 g and 0.2 g water respectively. 4 hydromycosis or mold mildew. Mainly caused by mechanical injury or frostbite, the diseased fish is sluggish, and there is a mass of cotton-like substance on the fish. If it is not treated, it will slowly die. At this point can be used four millionth of baking soda and four-thousandths of salt mixed with water solution Quanchiposa or per cubic meter of water with 0.1 grams of potassium permanganate solution Quanchiposa, 2 consecutive times, once per day. 5 fish fry enemy - water snake. Water snakes are generally caught during the night patrol, or placed in the pond with banana stalks. They are pulled ashore every few days. If there are snakes in the stem, they will naturally slip out and kill them. Of course, when clearing the pond embankment before entering the winter, try to plug loopholes and prevent water snakes from hiding. It can also be effective in reducing the survival of water snakes, and it will have a positive effect on wintering fry and increasing the survival rate.
Preparation before winter
1. Clearing ponds should be prepared before and after October of each year for disinfection of winter fry. The size of overwintering area should be selected based on actual conditions. Back-to-north direction should be selected as far as possible. Drainage and irrigation should be convenient, with an area of ​​over 1 mu, and the water depth should be maintained at 80 cm or more. Prepare stocking ponds for wintering seedlings. Disinfect the ponds thoroughly before putting the fishes. It is best to dry in water for one week and handle more than 15 centimeters thick mud (rinse with a mud-pumping machine or running water or discharge them out of the pond). .
Clearing ponds in the wintering ponds are also disinfected with the same fry before other seasons. Lime, tea bran or strong chlorine (bleaching powder) can be used for spilling. It is mainly to kill viral bacteria, miscellaneous fish and other natural enemies. Usage and dosage are shown in Table 1 (slightly).
Note: Tea bran should be crushed, soaked for 2-3 days, then boiled with boiling water, and then stir well, even the scum with Quanchiposa juice. Lime and strong chlorine powder (bleached powder) splashed in the whole pool after being mixed with water.
2. Preparation of fish species Stocking species for overwintering fry should be adapted to local conditions to suit their pond conditions and market needs. If the pond water temperature is maintained above 12°C and the water depth is maintained at more than 1.5 meters, consider warm water fish such as wild pheasants, earthworms and tilapia. If you don’t have safe wintering in stocking salmon in previous years, warm water fish need not be considered. Under normal circumstances, the average water depth is more than 1.2 meters per acre of water, and conventional stocking for wintering fry can refer to Table 2 (abbreviated).
Daily management
The daily management of wintering fry is first of all water quality management. In winter, the water temperature is lower, the fish eat less, the metabolites are less, the plankton is naturally reduced, and the transparency of the pool water is relatively high, which is not conducive to overwintering and growth of fish. Therefore, winter ponds are generally placed on the edge of ponds with pigs, ducks, chicken manure, or rice stalks after stacking, so that the water quality of ponds is refreshing, with a green bean color, and the transparency is maintained at about 20 cm. This will not only save feed costs, but also improve the survival rate of fry. Secondly, for feed feeding, when the water temperature is above 20°C, feed green feed (such as Sudan grass, ryegrass, oil cane, etc.) and concentrate feed (such as peanut bran, pellet feed, and grain sprouts) on a daily basis. . Generally, the daily amount of green feed accounts for about 6%-8% of the fish's body weight, and it is fed in the morning. The concentrate feed accounts for about 2%-3% of the fish's body weight. When the water temperature is lower than 15°C, no further feed is required. However, it should be noted whether there is any leakage in the pond and prevent the hypoxia or freezing of fry in the pond. Once again, the proper supplementation of new water, overwintering the pond for a period of time, will result in deterioration of the water quality. Therefore, if the conditions permit, on a sunny day, proper injection of fresh water will greatly benefit the growth and development of the fish.
Disease prevention and treatment
Most wintering fry are susceptible to bacterial gill disease at the beginning of winter, fish diseases caused by parasites before the beginning of spring, water blight at 15°C-25°C, or brucellosis after scraping fish.
1. Preventive measures: 1 Be careful to minimize fish injuries. 2 When the number of fry is too large, dip the fish fry for 10-15 minutes with 0.5%-0.6% saline or dip the fish with 0.1g of potassium permanganate solution per cubic meter for 5-10 minutes, and then put it again. pond. 3 Every 20-30 days, splash the limestone Quanchipi once, and use 15-20 kg per mu for 1 meter deep, splashing water at Quanchipi. 4 with tea bran (whole, should not break) per acre surface, a depth of 1 meter with 7-8 kg, placed in the middle of the pond and the middle, let it slowly dissolve, from the role of disinfection and regulation of water quality.
2, treatment: 1 bacterial gill disease. Symptoms: The diseased fish has a dark body color and travels alone. The lids are opened. There are many mucus on the silk, and some decay into a "open skylight" shape. This is a typical bacterial gill disease. At this time, the pond water body can be disinfected with quicklime (method is the same as preventive measure 3), and the next day with half a catty of trichlorfon (crystals) plus 2 coarse salty water, Quanchiposa (1 meter deep per acre), meanwhile The compound fish drug was fed continuously for 3-6 days. 2 small melon worm disease. Popular in water temperature 15 °C -25 °C, the symptoms: sick fish swim slowly, floating on the water, sometimes the cluster around the pool, check the sick fish fish, fins, chin, there are many small white spots. At this time, 1 meter of water per acre can be used half a catty of dry chili and 2 pieces of dried ginger, boiled with 4 pounds of water and boiled for half an hour. Then even the scum with a splash of Quanchipa, for 2 consecutive days, once a day, can be expected Effect. 3 Other fish diseases caused by parasites. Mainly in the late winter and early spring, larger individual fish fry, caused by poor water quality, such as trichomonads, hidden whipworm, pupa tuberculosis and other diseases, then can use buckwheat leaves and leaves water, every 40 kg of water per 667 cubic meters of water tied into The piled up near the inlet can achieve the purpose of prevention. It can also use copper sulphate and ferrous sulphate mixture. Each cubic metre of water is splashed with 0.5 g and 0.2 g water respectively. 4 hydromycosis or mold mildew. Mainly caused by mechanical injury or frostbite, the diseased fish is sluggish, and there is a mass of cotton-like substance on the fish. If it is not treated, it will slowly die. At this point can be used four millionth of baking soda and four-thousandths of salt mixed with water solution Quanchiposa or per cubic meter of water with 0.1 grams of potassium permanganate solution Quanchiposa, 2 consecutive times, once per day. 5 fish fry enemy - water snake. Water snakes are generally caught during the night patrol, or placed in the pond with banana stalks. They are pulled ashore every few days. If there are snakes in the stem, they will naturally slip out and kill them. Of course, when clearing the pond embankment before entering the winter, try to plug loopholes and prevent water snakes from hiding. It can also be effective in reducing the survival of water snakes, and it will have a positive effect on wintering fry and increasing the survival rate.