How should spring fish ponds be managed? How should common diseases be treated? Take a look at the great ways here
As the saying goes, the solution of the year lies in spring, and spring is the beginning of an aquatic production cycle. In the spring, if the fish pond is managed well, the water quality is well regulated, and the fish are less sick, or even no disease, they can reduce losses and improve efficiency. The following author talks about his own understanding according to his own practice.
In mid-to-late March, the water temperature of the pond gradually rises, and various pathogens begin to produce and multiply. At this time, the farmed fish have not eaten for a winter, and the water temperature has not yet reached the feeding temperature, which is the worst stage of the physique of the farmed fish, and the pathogen will take advantage of the void and cause harm to the fish, and it is crucial to prevent it as soon as possible.
<h1 class="pgc-h-arrow-right" >, completely clear the pond</h1>
1. Quicklime clear pond
The first is to clear the pond by drying the pond, drain the pond, and dig a number of small pits at the bottom of the pond so that the whole pond can be spilled. Quicklime is placed in a small pit according to the amount of 50-75 kg per acre, and after absorbing water, it is sprinkled hot. The second is to clear the pond with water, and the whole pond is sprinkled after melting at a depth of 1 meter per mu of water. Fry can be stocked after 1 week.
2. Bleaching powder clear pond
After adding water, it can generate hypochlorous acid, release oxygen, have a strong bactericidal effect, and can also kill harmful fish and its aquatic organisms, characterized by small dosage, easy to operate, and the medicinal effect disappears quickly. The dosage is calculated according to 20 grams per cubic meter of water, the whole pond is sprinkled, and the fry can be stocked after 5 days of medication.
<h1 class = "pgc-h-arrow-right" > second, fish body disinfection</h1>
1. Bleach powder
For the prevention and control of bacterial diseases on the surface of fish, the use is to soak the seedlings with a solution containing 30% bleach powder 10 ppm before seed stocking, for a period of about 15 minutes.
2. Table salt
Soaking seedlings with salt water concentration of 2%-2.5% for about 10 minutes can prevent gill rot, wheelworm disease, whitehead white mouth disease and so on.
3. Copper sulfate
Soak the seedlings with 8ppm concentration copper sulfate solution for about 20 minutes, which can prevent cryptoflagellosis, oblique tubeworm disease, silver carp and Chinese bream disease.
4. Potassium permanganate
The immersion concentration is 20ppm, and the water temperature is 10~20°C, and the immersion is 2~2.5 hours. This method is mainly used for the prevention and control of anchorhead loach and new loach disease, three generations of insect diseases, etc.
<h1 class= "pgc-h-arrow-right" > third, bait disinfection</h1>
Disinfection of bait is an important part of the production process. If it is plant-based bait duckweed, morning grass, etc., it is best to soak in 5ppm bleaching powder solution for about 25 minutes; If it is animal food, it is better to be fresh and clean.
<h1 class="pgc-h-arrow-right" >4. Tool disinfection</h1>
The nets used in fishery production should be soaked in 5% salt water for 30 minutes before use and then exposed to the sun, and other fishing gear can be disinfected with 5% bleach powder solution, washed in clean water and reused. Metal fishing gear should not be sterilized with bleach and potassium permanganate.
<h1 class = "pgc-h-arrow-right" > five, food field disinfection</h1>
In the season of high temperature fish disease, disinfection is carried out in the food field every half a month, and 6 hanging bags are hung in the food field frame, and each bleach is placed 100 grams, which is hung for 3 days for a cycle.
< h1 class = "pgc-h-arrow-right" > six, the prevention and treatment of common diseases</h1>
1. Skin mold disease
Caused by skin mold infection. Symptoms are manifested by white fine hairs growing outward from the wound, invading inward and penetrating deep into the muscles, and the sick fish swimming abnormally, refusing to eat, and dying of thinness.
Prevention and control methods
(1) Thoroughly clearing the pond to kill pathogenic bacteria before the fry are stocked can effectively prevent this disease.
(2) In the production operation, try to avoid scratches such as fish bodies by nets.
(3) Before releasing seedlings, it must be bathed with table salt or potassium permanganate solution.
(4) Thiosefloxacin 0.5-1 ppm, medicinal bath for 3-5 minutes.
(5) Mix griseofulvin into the feed and calculate it according to 25 mg per kilogram of fish body weight.
2. Gill rot disease
The gills of the sick fish rot with sludge, the inner epidermis of the gill cap is hyperemic, and the middle part is often corroded into a small circular transparent window. The gills are swollen, mucus is increased, and the terminals are defective.
(1) Bacterial and fungal gill rot disease is sprinkled with dibromohydantoin 0.3ppm in the whole pond, and at the same time, it is mixed and fed for 3 to 6 days with fish funning, allicin, and violent hemophoresis at a rate of 0.2%.
(2) The gill rot caused by wheel worms and ringworms is sprinkled with powerful insecticides or fungal killers, and its concentration is 0.01-0.02ppm; Take the fishing insect g internally and feed it 2 times. 200 grams per 100 catties of feed; Sprinkle with compound effect multiplier enemy insects 150 grams per acre.
3. Small melon worm disease
Symptoms are small white dotted vesicles that can be seen in various parts of the surface of the fish body, and in severe cases, the fins are decayed, the scales are shed, and there is a large number of parasitism on the gills.
(1) Thoroughly clear the pond with quicklime.
(2) According to the dosage of 250 to 500 grams of dried peppers per mu at a depth of 1 meter, mash the dried peppers in the pot, add water to boil, and sprinkle the fish pond once a day for 3 consecutive days.
4. Enteritis
The pathogen is Aeromonas pneumaticis. Symptoms are manifested by a decrease in appetite shortly after the onset of the disease, swelling of the abdomen, redness and swelling of the anus, darkening of the body color, and swimming in isolation. A slight squeeze of the abdomen allows yellow mucus to flow out of the anus. There is no food in the intestine, there is yellowish mucus, and the inner wall is eroded.
(1) Sprinkle the whole pool with bleach powder 1ppm concentration every half month, which can be prevented.
(2) During treatment, 0.3g/m3 bromochlorohydantoin can be used to disinfect the aquaculture water body, and at the same time, 2‰ to 3‰ of allicin is added to the feed for internal administration, and continuous feeding is carried out for 5 days.
(3) For fish that have no food intake due to severe disease, isomalto-oligosaccharides can be fed every day to ensure that 15g per fish per day is insisted on for 2 weeks, which can inhibit pathogenic bacteria.
5. Grass carp hemorrhagic disease
The causative agent is reovivirus. The symptoms are that the organs and tissues of the diseased fish have different degrees of congestion and bleeding. The fish body is dark, and the small fish species can be seen in sunlight or light perspective, and the subcutaneous muscles are congested and bleeding; The mouth, upper and lower jaws, top of the head, around the orbit, gill caps, gills, and the base of the fins are hyperglycrated, sometimes protruding from the eyeballs. Peeling off the skin of the fish, the muscles can be seen to be dotted or lumpy, hyperemic and bleeding, and in severe cases, the muscles of the whole body are bright red, at which time the gills often show "white gills"; The intestinal wall is hyperemic, but still tough, and there is no food in the intestine: the mesentery, peripheral fat, bladder, gallbladder, liver, spleen, kidney also have bleeding spots or blood capillaries, and some bladder and gallbladder are purple-red; When muscle bleeding is severe, the color of the liver, spleen, and kidneys often fades.
(1) Injection or soaking grass carp hemorrhagic disease tissue plasma inactivated vaccine or cell weakening vaccine for prevention, more effective, but the disadvantage is time-consuming and labor-intensive.
(2) During the onset season, the whole pool is sprinkled with chlorine dioxide, surfactants and other disinfectants, which have a certain effect on the simulated virus.
In summary, the spring release of seedlings must be selected healthy and lively body harmless seedlings, before the release must be cleared pond, so that the pathogen can be completely killed, effectively reduce the occurrence of diseases of farmed fish. In the usual daily management, it is necessary to adhere to the disinfection of aquaculture water bodies once every half a month, or to adjust the water quality with micro-ecological preparations, so as to improve the survival rate, reduce costs, and enhance the efficiency of aquaculture.