CATDOLL : CATDOLL: What diseases need to be prevented and treated in farmed snakehead fish?

1. What diseases need to be prevented and treated when breeding young snakehead fish?

Cultivation of fish fry

The newly hatched fry have a swollen yolk sac in their abdomen. After the yolk sac is absorbed, they are fed egg yolk twice a day and a certain amount of small zooplankton. After 2 days, they can be transferred to the nursery pond for cultivation.

1. The nursery pond area is 60-100 square meters and the water depth is 60 centimeters. The nursery pond should be cleaned with quicklime 2 weeks in advance. After filling the pond with water, add 100 kg of fermented organic fertilizer to cultivate zooplankton. Sprinkle soybean milk throughout the pond two days before the fry are released.

2. Stock the fish pond with 5,000 fry per square meter. At first, feed them with artificially caught rotifers, cladocerans, and copepods. Then, artificial fertilizers and soy milk are applied to the pond to cultivate zooplankton. After one week, a certain amount of sexually mature fish such as wheatear fish and silver carp are placed in the pond to allow them to spawn naturally.

Breeding fry as bait fish. Snakehead fry grow fast. During the domestication process, they are fed with some wild fish and artificial synthetic feed. When the fry are about 3 cm long, they can be divided into ponds for breeding. This stage takes about 20 days.

(II) Fish breeding

1. Clean the fingerling pond with quicklime or bleaching powder as usual and disinfect it, and cultivate zooplankton.

2. The stocking density is 60,000 to 70,000 per 0.067 hectares.

3. Feed the fish with domesticated bait, some wild fish and shrimp and artificial compound feed. 500-600 snakehead fish with a body length of 3 cm need 500 grams of chopped shrimp every day, and then increase 250 grams every 5 days.

4. Strengthen feed management. First, the fry should be placed in the pond in the early morning in the windward position. Second, the fry must be placed in the pond with fertilized water to prevent the fry from suffocating and dying. On hot and humid nights, the fry should be evacuated in time to prevent them from swarming. Third, after half a month of feeding, if the fry are found to be of different sizes, they should be separated into different ponds to imitate the big fish eating the small fish. Fourth, the water quality must be adjusted during the fish seed breeding process. The cement pond should be watered once every 1 to 2 days, and the earth pond should be watered once every 7 to 10 days, with each watering of 20 to 30 cm. Quicklime should be sprinkled regularly at a concentration of 10 to 20 ppm. Biological water quality regulation is to release 500 silver carp per 0.067 hectares to feed on phytoplankton and control the water quality from being too fertilized. After 2 months of breeding, the black snakehead fry can reach a body length of 8 to 13 cm and can be put into the adult fish pond for breeding as fingerlings.

2. The dace I keep at home is infected with bacteria, but I don’t know what the disease is! What should I do? Please give me a good prescription!!

Xiaobai, give it a thumbs up

3. Please ask experienced masters for advice on how to raise pond flea fish and how to prevent and treat common diseases. Thank you~~~

1. Scientific stocking Eels are temperature-changing animals. As long as the water temperature is between 10 and 32 degrees Celsius, they can be stocked all year round. Stocked eels are required to be healthy, active in swimming, free of disease and disability, and of any size. Because eels tend to bully the small and the weak, and bite each other for food when food is scarce, the eels raised in the same pond should have basically the same size. Generally, eels weighing more than 100 to 350 grams can be placed in the waiting pond for sale at any time; eels weighing more than 50 grams can be placed in the cultivation pond and can grow to commercial specifications in the same year; eels weighing less than 50 grams can be placed in the seedling pond and can grow to more than 50 grams in the same year, providing large-sized eel species for eel cultivation next year. The stocking density should be flexibly controlled according to the stocking specifications and feeding conditions, and generally 1 to 5 kilograms are stocked per square meter of water surface. 2. Preparation for entering the pond Before the eels enter the pond, a small amount of fermented and decomposed organic fertilizer can be applied to breed aquatic animals such as chironomid larvae, silk earthworms, aquatic insects, etc., or snails or loaches can be placed in the pond and allowed to breed to provide fresh bait for fresh fish. Where conditions permit, black light lamps can be set up in the pond to lure insects into the pond. 3. Feeding After 1-2 days of short-term adaptation, the bait can be fed, and the amount of feed is generally 2%-10% of the total weight of the fish. The amount of feed should be increased or decreased as appropriate according to the water temperature, bait quality, water quality, etc. Generally, feed once a day. Feed at 4-5 pm or in the evening. You can also gradually advance the feeding time to tame it during the day, feeding once at 8 am and 4-5 pm. Eels mainly feed on animal baits, and they like to eat fresh baits, such as various insects and their larvae, earthworms, small fish and shrimps, silkworm pupae, maggots, snails, clams, large zooplankton, livestock and poultry viscera and tadpoles. The bait should be fresh and not rotten. In places where animal baits are insufficient, some plant baits, such as bean cakes, bran or corn flour, can be fed. The above plant baits are mixed with minced fish and shrimp meat into a wet ball (which can stay in the water for a long time) and then fed. Larger baits should be chopped or hung in the pond and allowed to be torn and eaten. The shells of hard-shelled baits such as snails, river clams and cockles must be smashed before being put in. The bait should be fed at a fixed point, and each fish pond should have 2-8 feeding points. The suitable water temperature for eels to feed is 15-30℃, and they have the habit of hiding during the day and coming out at night to feed. If the fish pond is covered with plastic film greenhouses or other warming and insulation measures are adopted in winter to maintain a suitable water temperature, eels can feed and grow throughout the year, thus greatly shortening the short breeding period, reducing costs, and increasing production and benefits. Before feeding, the residual bait should be removed to avoid affecting the water quality. 4. Adjust the water level and water quality. Because eels can breathe oxygen directly in the air, they need to often stick their heads out of the water. Therefore, the water level in the fresh fish pond should be shallow. The water level should be determined according to the specifications of the eels. The water level in the seedling pond should be shallow, generally 10-20 cm. The cultivation pond can be deeper, generally 30-40 cm. The water level in the pool for sale can be shallower. Eels consume a lot of oxygen and like fresh water quality. Therefore, new water should be injected frequently. Generally, the water should be changed 1-2 times a month in winter, once a week in spring and autumn, and once every 1-3 days in summer. The amount of water changed each time is 20-50%. Micro-flow water can be formed in the eel pond where conditions permit. In the hot season, the number of water changes should be increased, or loofahs and grapes should be planted on the pond to prevent exposure to the scorching sun and to cool down and prevent heatstroke. In larger and deeper eel ponds, a small amount of omnivorous fish such as tilapia, carp, crucian carp, and loach can be mixed to remove residual bait and feces and purify water quality. 5. Timely screening and pond division The eel species are very competitive. After a period of breeding, the fish in the same specification will have uneven specifications, which is not conducive to the increase of production in the long run. Therefore, during the growth period of eels, all eels in the pond should be caught every 1 month or so, and after screening, large, medium and small eels should be raised in separate ponds. Before the end of the growth period after autumn, all fish should be caught, and the fish that have reached the commercial specifications should be put into the waiting pond for sale. The rest of the fish of different specifications should be stocked in separate ponds according to the production needs of the next year. In this way, after a winter of adaptation, the eel species can enter the vigorous growth stage earlier next year. 6. Prevention and control of fish diseases Before stocking, the eel pond must be cleaned and disinfected with quicklime or bleaching powder. Foreign eels must be disinfected with a bleaching powder solution with a concentration of one millionth, or 3% salt water for 10-20 minutes before being put into the pond. During the breeding period, the entire pond should be sprinkled with bleaching powder at a concentration of one millionth every month. Dragging and washing the scalped toads in the pond has a certain effect on white spot disease and rotten skin disease. 7. Do a good job in protection. The eel pond is small and shallow. When pouring new water, prevent water from overflowing and fish from escaping. The water surface of the fish pond should be controlled below 20 cm from the edge of the pond, and the firmness of the fish intercepting net cloth and the pool wall of the inlet and outlet gates should be checked at any time. Especially when there is a lack of food, thunderstorms, long rainy weather or water quality deterioration, eels are most likely to escape, and escape prevention should be paid more attention at this time. In addition, ducks, rats, cats and other predators should be prevented from harming eels. 8. Wintering Management Generally after November, when the water temperature drops below 15℃, eels begin to drill deep into the soil and enter hibernation until February-March of the following year. During the winter, warming and heat preservation measures should be taken in the waiting pool. Eels that do not meet the commercial specifications of the year can overwinter in the original pool, and a higher water level can be maintained during the winter. Especially when the water surface is frozen, the water depth under the ice should be kept at more than 0.3 meters, and the pool water should be changed once a month. Dry wintering can also be adopted, that is, when the water temperature drops below 10℃, drain the pool water, cover the bottom of the pool with some wheat straw or rice straw, keep the soil moist and not frozen, and the eels can safely overwinter. In places with heat sources, keep the pool water at 25-30℃ all year round, and the eels can avoid hibernation and grow all year round.