<h2 class = "rich_media_title" in June, > the country entered the early summer season, the temperature rose, the water temperature also rose significantly, and aquaculture entered the peak production season. With the increase of aquaculture animal feeding, the residual bait and excrement in the aquaculture water body gradually increased, resulting in poor water quality, coupled with the increase in high temperature and sweltering weather, the proliferation rate of pathogenic microorganisms accelerated, at the same time, the middle and lower reaches of the Yangtze River and the southern coast were affected by the rainy season and typhoons, the sweltering and rainy, the weather was changeable, it was very easy to cause sudden changes in the water quality of the breeding environment, the stress response of aquaculture animals intensified, and the occurrence and epidemic of diseases were aggravated. According to the analysis, the following diseases need to be paid attention to across the country in June this year. </h2>
First, the diagnosis of the disease
(1) Fish diseases
1. Grass carp hemorrhagic disease: the pathogen is grass carp reovirus, mainly harmful to grass carp fingerlings, water temperature is easy to occur at 20 ~ 30 °C, 25 ~ 28 °C is the peak of the epidemic, the main transmission route is horizontal transmission, may also be vertically transmitted through fish eggs. The main grassland carp rearing areas need to focus on prevention and control.
2. Carp edema disease: the pathogen is carp edema virus, mainly harmful to carp and koi, the onset of water temperature is 7 ~ 28 °C, seedlings carrying pathogen circulation is the main way of transmission and spread of the disease, water change, improper medication or water quality, weather mutations, can induce outbreaks of the disease. All carp and koi breeding areas need to focus on prevention and control.
3. Koi herpes virus disease: the pathogen is koi herpes virus type III( also known as koi herpes virus), which mainly harms carp, koi and its variants, and is easy to circulate when the water temperature is 18 ~ 28 ° C, mainly through water bodies, diseased fish feces, mucus and other levels of transmission. All carp and koi breeding areas need to focus on prevention and control.
4. Crucian carp hematopoietic organ necrosis: the pathogen is carp herpes virus type II, mainly harmful to crucian carp, goldfish and crucian carp hybrid variants, water temperature 10 ~ 33 °C can occur, of which 22 ~ 28 °C is the most serious, the main transmission route is horizontal transmission. The main breeding areas of each crucian carp need to focus on prevention and control.
5. Viral neuronecrosis: also known as viral encephalopathy and retinopathy, the pathogen is viral neuronecrosis virus, mainly harmful to groupers and other marine fish baby fish, water temperature at 25 ~ 32 °C is prone to disease, pathogens can be transmitted horizontally through the water body, but also through the parental vertical transmission to offspring. The main rearing areas of marine fish breeding such as grouper need to focus on prevention and control.
6. Freshwater fish bacterial sepsis: the pathogen is mainly hydrophilic aeromonas, harmful crucian carp, tuantou bream, silver carp, bighead carp and other freshwater fish, water temperature in 9 ~ 36 °C are prevalent, the disease can be spread through diseased fish, bacteria pollution of bait, utensils and water sources, birds prey on diseased fish can also cause disease spread between different breeding ponds. All freshwater fish farming areas across the country need to focus on prevention and control.
7. Bacterial enteritis disease: the pathogen is intestinal punctate aeromonas, guinea pig aeromonas, mainly harmful to grass carp, bluefish, carp and other freshwater fish, water temperature above 20 ° C epidemic, the peak of the epidemic is 25 ~ 30 ° C, often with bacterial gill disease, red skin disease, etc., is one of the more serious diseases in farmed fish. All freshwater fish farming areas in the country need to focus on prevention and control.
8. Stimulate cryptonuclear worm disease: commonly known as "white spot disease" or "seawater melon worm disease", the pathogen is to stimulate cryptonuclear worm, mainly harmful to yellow croaker, oval pomfret, grouper and other marine aquaculture fish, stimulate cryptonuclear insects suitable propagation water temperature of 10 °C ~ 30 °C, the most suitable breeding water temperature is about 22 °C ~ 26 °C, to the cyst and larvae spread, infection speed, with high pathogenicity and high outbreak, high content of water quality organic matter, slow water flow, breeding density is too large the most prone to outbreak. All marine fish farming areas across the country need to focus on prevention and control.
9. Wheel worm disease: the pathogen is wheel worm, mainly endangering a variety of freshwater fish seed, the country's fish farming areas, all year round have occurred, suitable water temperature 22 ~ 29 ° C, the main symptom is the sick fish head and mouth around the slight white, secrete a lot of mucus, usually fish fry stocking 10 days after the disease, flocks of wild swimming along the pond, commonly known as "horse racing disease". All freshwater fish farming areas across the country need to focus on prevention and control.
(2) Crustacean diseases
1. Leukoplakia syndrome: the pathogen is leukoplakia syndrome virus, the main harm object is Penaeus vannamei, Chinese shrimp, Japanese shrimp, protocrayfish Crawfish, etc., the water temperature is prevalent at 20 ~ 30 ° C, oral infection is the main way of infection and transmission of leukoplak syndrome virus in farmed shrimp, the virus can also be transmitted vertically through the eggs of shrimp. The main coastal shrimp culture area needs to focus on prevention and control. In addition, the main cultivation areas of Ke's original crawfish in Hubei, Jiangsu, Anhui, Jiangxi and other places also need to strengthen the prevention and control of the disease.
2. Shrimp iridescent virus disease: the pathogen is decanter iridescence virus 1, mainly harmful to South American white shrimp, giant river prawn, Japanese giant shrimp, protocampus crawfish, etc., shrimp body length of 4 ~ 7 cm is most susceptible to infection, water temperature at 16 ~ 32 °C when the epidemic, cannibalism and other ways of horizontal transmission, with the virus seed circulation is an important reason for the rapid spread of the disease. The main culture areas of prawn and giant river prawn need to be controlled and controlled.
3. Acute hepatoscreascreassis necrosis: is a bacterial disease that endangers farmed shrimp, the main harm object is Penaeus vannamei, Penaeus monodon and Chinese shrimp, etc. At present, the main marine aquaculture shrimp areas in China have the epidemic of the disease, death mainly occurs within 30 to 35 days of seedlings, often acute death, and the mortality rate is as high as 100%, oral infection is the main way of transmission of the pathogen level. The main coastal shrimp culture area needs to focus on prevention and control.
4. Shrimp liver and intestinal cytozoan disease: the pathogen is shrimp liver and intestine, which can infect shrimp at all stages of life, mainly harming Penaeus vannamei and Penaeus monodon, the infection rate is high at water temperature of 24 ~ 31 °C, and horizontal transmission is the main way for the pathogen to spread and infect shrimp in the breeding pond. The main coastal shrimp culture area needs to focus on prevention and control.
In addition, during this period, fish also need to pay attention to the prevention and control of mandarin infectious spleen and kidney necrosis, catfish intestinal sepsis, tilapia streptococcal disease, rotten gill disease and other diseases, crustaceans pay attention to the prevention and control of nodamura virus disease, Dora syndrome, ciliates and other diseases, reptiles pay attention to the prevention and control of Chinese turtle rot skin disease and other diseases and non-pathogenic diseases caused by deterioration in water quality, weather changes, hypoxia, red tide, etc. May have an impact on aquaculture production.
2. Prevention and control measures
(1) Scientific feeding to ensure the quality of bait. When feeding feed, adhere to the "four certainties" principle of timing, positioning, quality and quantity, and flexibly grasp the feeding amount according to the weather, water quality and fish body activity feeding situation. Green bait requires green and refreshing, and the combination of bait requires reasonable formula and comprehensive nutrition.
(2) Regular disinfection to maintain good water quality. After the water temperature rises, all kinds of pathogens begin to be active, once encountered in an unstable environment, it is very easy to induce diseases, regular use of quicklime and other disinfectants and environmental improvers to do water disinfection, adjust water quality and improve the substrate, so that the transparency of the water body, dissolved oxygen, pH value, etc. are maintained in a suitable state.
(3) Timely oxygenation to prevent pond flooding. High temperature and sweltering heat, rainy weather is easy to cause water lack of oxygen and the occurrence of ponds, we must pay close attention to weather changes, actively prepare for heavy rain and typhoons, strengthen daily management, and find that hypoxia should be timely to open the aerator, fill new water and other measures to prevent ponds.
(4) Prevent blind medication. Once the disease occurs, it is necessary to consult the professional and technical personnel of aquaculture disease prevention and control in time or consult experts through the "National Aquatic Animal Disease Remote Auxiliary Diagnosis Service Network", and remember to blindly use drugs to avoid unnecessary losses.
(5) Timely reporting of the epidemic situation. In the production process, once it is found that there is a large-scale disease and a large number of deaths of farmed species, it is necessary to report to the local aquatic technology promotion (aquatic animal disease prevention and control) institution in time, and take corresponding measures to prevent the spread of the disease. (Source: National Aquatic Technology Promotion Station)
Aquaculture disease forecast in Guangdong Province for June 2020
In June, the temperature and water temperature in Guangdong Province gradually rose, and there were more thunderstorms, which were affected by environmental factors and gradually increased the number of aquatic animal diseases. Before and after thunderstorms, we should pay close attention to the changes in the water quality and environment of the breeding ponds, timely monitor various physical and chemical factors, and take preventive measures to deal with diseases caused by sudden changes in the environment. According to the data analysis of monitoring results in previous years, the increase in bacterial diseases, especially streptococcus, aeromonas, shrimp vibriosis, hepatoborocreas necrosis syndrome, marine fish stimulation cryptonuclear worm disease and other outbreaks in local areas, we must pay attention to precautions in advance.
(1) Freshwater fish: prone to bacterial sepsis, gill rot, enteritis, ulcer disease, nocardiosis, wheelworm disease, ringworm disease, etc., focusing on grass carp, snakehead, sea bass and other species.
1. Grass carp: the fingerling stage is prone to hemorrhagic disease, gill rot disease, focusing on pond culture areas with low immunization rates.
2. Snakehead: prone to nocardiosis, focusing on the main area of the Pearl River Delta.
3. Tilapia: prone to streptococcal disease, focusing on the main culture areas of western Guangdong and the Pearl River Delta.
4. Perch: prone to iridescent virus disease, focusing on the Pearl River Delta region.
(2) Marine fish: parasitic diseases such as stimulating cryptonuclear insect disease are prone to occur, focusing on Chaozhou City, Huizhou City, Zhuhai City, Yangjiang City and Zhanjiang City.
(3) Shrimp: prone to iridescent virus disease, vibriosis, acute hepatobatic and pancreatic necrosis, etc., focusing on the Pearl River Delta and the main breeding areas of western Guangdong.
(1) Strengthen testing and quarantine efforts. Through testing and quarantine measures, high-quality seedlings are selected from the source, and the virus carried by the seedlings is prevented from being released into the breeding environment, so as to ensure the quality of the seedlings and enhance the disease resistance of the seedlings.
(2) Frequent thunderstorms, fish ponds are prone to flooding due to lack of oxygen, pay attention to observe the water quality and feeding of fish and shrimp, find that hypoxia should be filled with new water in time, and take measures such as oxygenation, if necessary, put oxygenizers. Regularly sprinkle microbial agents and substrate improvers to regulate water quality, and appropriately reduce the amount of bait before heavy rainstorms, and add vitamin C, immune enhancers and anti-stress drugs to prevent sudden changes in the water environment from causing stress and violent diseases.
(2) Do a good job of clearing the pond disinfection work before releasing seedlings, use quicklime or bleach powder to sprinkle the whole pond to kill pathogenic bacteria and remove predators, use microbial preparations to regulate water quality, after the weather is stable, choose to put seedlings in the pond without abnormal circumstances after testing the water on sunny days, and before the seedlings are planted in the pond, do a good job of disinfection work and stress work in time to avoid disease outbreaks and stress deaths. After the seedlings are planted in the pond, it is necessary to strengthen the management of breeding and production, especially to do a good job in the prevention and control of parasitic diseases, control the density of breeding, feed multi-dimensional and immune enhancers and other enhancement physique, provide disease resistance, and achieve the principle of focusing on prevention and combining prevention and control.
Disease prevention and control methods should be implemented according to the actual situation of the farmed species and under the guidance of relevant professional institutions or technical personnel. (Source: Guangdong Provincial Center for Animal Disease Prevention and Control)
Aquaculture disease forecast in Jiangsu Province in June 2020
In June, Jiangsu is about to enter the high temperature and rainy season, and thunderstorms occur from time to time. Aquatic animals have also begun to enter the peak growing season, feeding is exuberant, aquatic animal metabolites in the water body increase, water quality is easy to deteriorate, and various harmful bacteria begin to breed. Prevention should be strengthened to reduce the economic losses caused by diseases to aquaculture production.
(1) Fish bacterial sepsis, enteritis disease, gill rot disease: freshwater fish high-density breeding areas need to focus on prevention and control.
(2) Crucian carp hematopoietic organ necrosis: focus on Yancheng, Taizhou, Yangzhou, and other areas.
(3) Mandarin fish infectious spleen and kidney necrosis: focus on mandarin fish breeding areas in Yangzhou, Suzhou and other regions.
(4) Crustacean ciliate disease, gill rot, enteritis disease, shrimp leukoplakia syndrome: focus on shrimp and crab areas such as Yancheng, Nantong, and Huai'an.
2. Prevention and control measures
(1) Myxosporidiosis of fish: avoid purchasing seed in the epidemic area for breeding. Avoid the introduction of water from the epidemic area to the breeding pond, do a good job of disinfecting the pond, eliminate the water earthworms in the water body and the sediment, and kill the dormant spores. Treatment should be fed using nationally prescribed antiprotozoal drugs for aquaculture or other insecticide-repellent mixtures
(2) Fish gill rot disease: thoroughly clear the pond, and organic fertilizer after full fermentation should be applied when fertilizing the fish pond; Select high-quality healthy fish fingerlings, fish body soaking and disinfection measures should be carried out before the fish species are put into the pond, and the diseased fish pond can choose to use Chinese herbal medicines such as double yellow bitter ginseng powder, green plate yellow cedar powder, three yellow powder, plate blue root end, rhubarb powder, rhubarb fish powder and rhubarb five-fold seed powder, and the dosage is carried out according to the instructions for use.
(3) Fish enteritis disease: do not feed spoiled feed, cultivate robust fish species, strengthen feeding management, feed comprehensive nutrition and high-quality feed, maintain excellent and stable water quality, and improve the resistance of fish. Sick fish can be treated with Chinese herbal medicine or taken internally (on the basis of drug susceptibility tests), and the dosage is carried out according to the instructions for use.
(4) Infectious spleen and kidney necrosis of mandarin fish: reduce the density of fry culture and reduce environmental stress. Strengthening feeding management and strictly disinfecting water sources, breeding eggs and broodstock, introduced fry and corresponding facilities can cut off the source of infection and reduce the probability of viral infection. Broodstock found positive are treated in a timely manner to cut off the vertical transmission route of the virus. If a diseased fish is found, it must be destroyed in its entirety after being diagnosed, and the water source and utensils must be treated harmlessly.
(5) Crustacean leukoplakia syndrome: 1. Healthy shrimp that have been quarantined without pathogens are selected as broodstock when breeding; 2. Do a good job in dredging and disinfection of breeding ponds, use quicklime or chlorine disinfectant to evenly sprinkle the whole pond, and then enter the water after disinfection for about 1 week. Cultivate the water color during the breeding process and maintain excellent water quality. 3. Combine the local water source, environment, shrimp pond structure and breeding equipment, production technology, management experience, shrimp fry specifications, feed quality and other comprehensive conditions, reasonable stocking density. 4. In the process of feeding management, we must pay attention to the changes in water quality and various physical and chemical factors, maintain the relative stability of the water body; adhere to the pond patrol, regular inspection, correct diagnosis, and active prevention.
(6) Other matters needing attention
Reasonably start the aerator to improve the dissolved oxygen of the water. Pay attention to weather changes, pay special attention to sudden weather forecasts such as heavy rainfall, strengthen breeding facilities in time, beware of lack of oxygen in pond water, pay attention to the stress response of farmed aquatic animals, and take effective countermeasures in a timely manner. In the process of river crab breeding, the use of drugs is standardized, and prevention is more important than treatment. Add Chinese herbs and minerals to the feed to promote the digestion and absorption of river crabs, enhance appetite and improve body immunity, and enhance the disease resistance of river crabs. (Source: Jiangsu Aquatic Animal Disease Prevention and Control Center)
Forecast of aquaculture diseases in Hubei Province in June 2020
June has entered the early summer season, aquaculture animals grow rapidly, feeding vigorously, the pond bait and excrement increase, pathogenic microorganisms multiply in large quantities, easy to lead to disease occurrence and epidemic. During this period, attention should not only be paid to the common and frequent bacterial and parasitic diseases, but also to the significant harm that some viral diseases may cause to aquaculture.
The common and frequent diseases of aquaculture in Hubei Province in June mainly include: bacterial sepsis of freshwater fish, gill rot, bacterial enteritis disease, wheelworm disease, yellow jaw fish bacterial disease, grass carp hemorrhagic disease, crucian carp hematopoietic organ necrosis, white spot syndrome, turtle ulcer disease, etc.
(1) Bacterial sepsis of freshwater fish: the main hazard objects are crucian carp, tuantou bream, silver carp, bighead carp, yellow eel, mandarin, California perch, etc., which have the characteristics of urgent disease course and high mortality rate. Over the years, the disease has caused great economic losses to the aquaculture industry in our province, and all breeding areas in the province need to focus on prevention and control.
(2) Gill rot disease: the disease generally begins when the water temperature is above 15 ° C, the higher the water temperature, the more likely it is to outbreak and epidemic, the shorter the time to death, is a more common fish disease. There are two main types of gill rot disease: parasitic gill rot and bacterial gill rot. The main hazard objects are blue carp, grass carp, crucian carp, tuantou bream, mandarin fish, California perch, etc., which should be paid attention to by various breeding areas.
(3) Bacterial enteritis: a disease caused by enteric punctate aeromonas infection. The main hazard objects are grass carp, blue carp, crucian carp, tuantou bream, yellow eel and so on. It is often complicated with bacterial gill rot disease and erythroderma, and is one of the most harmful diseases in farmed fish. When the water temperature is above 18 ° C, it is easy to get sick and cause epidemics.
(iv) Rotiferosis: a disease caused by large numbers and multiples of rotifer parasitisms on the skin or gills of fish. Suitable water temperature of 20 °C ~ 28 °C. Clinical symptoms are mainly "white head white mouth" or "running horse" (swimming around) and so on, is a parasitic disease that is more harmful to farmed fish, and occurs in fish farming areas throughout our province, especially in fish ponds where farming is dense, continuous rainy weather is especially easy to cause outbreaks.
(5) Yellow jaw fish bacterial disease: the pathogen is generally Vickers, Edwards virtus and so on. Clinical symptoms are mainly the sick fish swimming alone, or lying quietly at the edge of the pool; the head of the sick fish is red, black or "perforated", the skin on the surface of the body is ulcerated, the body color is yellow or the skin is discolored; the snout, the mouth, the jaw, and the gill cover are congested; the base of the dorsal fin, the base of the pectoral fin, and the tail fin are ulcerated; there is no food in the stomach and intestine, and some stomachs are filled with viscous fluid; the anus is red and swollen and bleeding, or there is ascites; liver blood loss, spleen blackening, and gallbladder is enlarged. The province's yellow jaw fish breeding area needs to focus on prevention and control.
(6) Grass carp hemorrhagic disease: mainly harmful to grass carp fingerlings and 1-foot-old bluefish. When the water quality deteriorates, the fish body resistance is low, which is easy to make grass carp hemorrhagic disease epidemic. The water temperature of the disease is 20 °C ~ 30 °C, and 25 °C ~ 28 °C is the most likely to occur. Breeding areas in the province need to focus on prevention and control.
(7) Crucian hematopoietic organ necrosis: caused by the infection of crucian carp by carp herpes virus type II ( CyHV-II.), with hemorrhage and hyperemia of body surface and internal organs as the main features, 15 ° C ~ 30 ° C can be onset, 25 ° C ~ 28 ° C is the peak of the disease epidemic. Breeding areas in the province need to focus on prevention and control.
(8) Leukoplakia syndrome: when the water temperature is 18 ° C ~ 30 ° C, the disease is prone to outbreak, the main harm object is South American white shrimp, crayfish, etc., our province crayfish breeding area and rice shrimp breeding area need to focus on prevention and control.
(9) Turtle ulcer disease: diseases caused by various bacterial infections such as aerophilic aeromonas and mild aeromonas, water temperature above 20 ° C are prone to disease and epidemic, the higher the temperature, the higher the incidence. In greenhouse culture, it occurs all year round, and juvenile turtles are susceptible to infection. Once the disease occurs, it lasts for a long time and is more harmful. The main areas such as public security and Jingshan in our province need to focus on prevention and control.
(1) Establish a scientific breeding management system. Pay attention to improving the bottom quality and water quality of the pond, cultivate a "fat, refreshing, tender and live" water body, provide a good living environment for fish, enhance the physique of fish, and improve disease resistance. Adopt scientific and standardized breeding measures to carry out healthy breeding and ecological breeding of aquatic products to improve the immunity of fish bodies; select varieties with strong disease resistance, reduce the incidence of disease, and reduce the use of fishing drugs.
(2) Bacterial diseases can be disinfected with quicklime or national standard fishing chlorine-containing and iodine-containing disinfectants, combined with drug susceptibility tests, using antibacterial drugs with high sensitivity and good bacteriostatic effect for mixing and feeding, and can be combined with the use of allicin, Chinese herbal medicine (such as compound three yellow powder, rhubarb essence) and vitamins at the same time to enhance the efficacy.
(3) The prevention and control of parasitic diseases should be based on the body structure and parasitic laws of different parasites to select appropriate drugs, and pay attention to the use method and dosage. For infected ponds, the national standard fishing drug dimethoate, copper sulfate ferrous sulfate compound (5:2), Chinese herbal preparations to deworm and other drugs can be used, and highly effective and non-toxic drugs can be selected as much as possible.
(4) There is currently no effective drug for the treatment of grass carp hemorrhagic disease, and the most effective control measure is to inject grass carp hemorrhagic disease inactivated vaccine or grass carp hemorrhagic disease live vaccine, and there are also some areas that use tissue pulp inactivated vaccine. In the onset season, the whole pond of povidone iodine is used for water disinfection, and the whole pool of disinfectants such as quicklime can also be sprinkled, which has the effect of prevention and auxiliary treatment.
(5) There is currently no effective treatment for leukoplakia syndrome, mainly based on prevention. Feeding high-quality feed enhances the physique and disease resistance of shrimp, maintains good water quality, controls the density of culture, and improves the habitat environment of shrimp. Prevention can be sprinkled in whole pools such as povidone iodine once every half a month. If shrimp are found to have disease, the diseased shrimp should be isolated in time to control the further spread of the disease. (Source: Hubei Institute of Fishery Sciences)
Aquaculture disease forecast in Guizhou Province in June 2020
In June, Guizhou Province predicted that the temperature would be between 15 and 31 °C, the water temperature of aquaculture would be between 13 and 26 °C, the aquaculture animals would be at the peak of growth and feeding, the residual bait excrement would increase, and the pathogenic microorganisms would also increase; at the same time, the extreme weather of heavy rain would cause a large temperature difference between day and night and the upper and lower layers of the water body, the water quality would change rapidly, the stress response of aquaculture animals would intensify, and the immunity would decline, which would lead to diseases.
(1) Bacterial sepsis: mainly harmful to silver carp, bighead carp, carp, grass, crucian carp and other freshwater fish, from summer flower fish species to adult fish can be infected, May to September is the peak period, water temperature 9 ~ 36 °C are prevalent, 25 ~ 30 °C the most serious disease, serious incidence of farm incidence of up to 100%, mortality rate of up to 95% or more.
(2) Bacterial enteritis: mainly harmful to grass, bluefish, carp, etc., the water temperature began to circulate above 18 °C, the onset of 25 ~ 30 ° C is the most serious, and the mortality rate is between 50% and 90%.
(3) Bacterial gill rot disease: the main harm to grass, green, carp, crucian carp, tilapia, etc., from fish species to adult fish can occur, popular in April to October, suitable water temperature of 15 ~ 30 °C.
(4) Koi herpes virus disease: mainly infected with carp and koi, the incidence of water temperature is mainly 2 ~ 28 °C, the peak of incidence is 22 ~ 28 °C, can lead to 80% ~ 100% mortality.
(5) Wheelworm disease: mainly harmful to fry and fingerlings, endemic in April to July, suitable water temperature of 20 ~ 28 °C, poor water quality, high organic matter content, stocking density is an important cause of the occurrence of the disease.
(6) Anchor head loach disease: this disease has a high infection rate, a long epidemic season, and can be propagated at 12 to 33 °C, focusing on silver carp, bighead carp, carp and carp species.
(7) Hypoxia: shrimp, grass, green, silver carp, bighead carp are prone to hypoxia, when the oxygen content in the water is low, resulting in hypoxia in aquatic animals, or the carbon dioxide content in the water is too high, affecting the release of carbon dioxide in the blood of aquatic animals, paralyzing the central nervous system, aquatic animals are difficult to absorb oxygen from the water, and will also cause the occurrence of hypoxia, causing floating heads, pan ponds, and suffocation deaths.
(1) Bacterial sepsis: remove the excessively thick silt and sprinkle it with quicklime or trichloroisocyanuric acid powder in the whole pool; mix and feed with florfenicol or thiamphenicol.
(2) Bacterial enteritis and bacterial gill disease: thoroughly clean the pond and disinfect to maintain clean water quality; feed fresh feed, do not feed spoiled feed; sprinkle bromochloroheine whole pond when the disease occurs; mix and feed with sulfa dimethiazine powder.
(3) Koi herpes virus disease: select breeding species with strong disease resistance to improve disease resistance; do a good job in isolation and quarantine and other preventive measures; strictly disinfect water sources, breeding eggs and broodstock, introduced fry and corresponding facilities, etc., and cut off the source of infection.
(4) Wheelworm disease: at the time of onset, it is sprinkled with 0.8-1.2 mg/L of copper sulfate or 1.2-1.5 mg/L of copper sulfate and ferrous sulfate mixture.
(5) Anchor head loach disease: when the disease occurs, the whole tank of the dinoflagellate solution with a concentration of 0.3 to 0.5 mg/L is used; a medicinal bath of potassium permanganate solution can be used, but it is necessary to pay attention to the resistance of the farmed species and grasp the time and concentration of the bath.
(6) Hypoxia: remove excessively thick silt from ponds; disinfect water bodies with quicklime or bleaching powder; improve water quality and substrate with microecological preparations; sprinkle oxygenizers, start aerators, and fill new water.
Aquaculture disease forecast in Liaoning Province in June 2020
In May, the temperature in Liaoning Province was lower than in previous years, and the rainfall was small. It is expected that the temperature will rise rapidly in June, and the water temperature of the culture pond will continue to rise, reaching 18°C-26°C, which is the best growing season for aquaculture species. Due to the short stocking time of pond seedlings and the light pollution of water quality, major diseases such as bacteria are not easy to occur. Freshwater fish focus on parasitic diseases, paying attention to various diseases such as parasites and white-headed white-moutheds in the summer flowering stage of various freshwater fry. Marine aquaculture pays attention to the various diseases of sea cucumbers, mudflat shellfish and jellyfish due to rapid temperature rises.
(1) Carp: prone to wheelworm disease and ringworm disease. Focus on the main breeding area and high-density intensive breeding area in the province.
(2) Freshwater fish summer flower: Silver carp, bighead carp and other conventional freshwater fish are prone to myxosporidosis, wheel worm disease, oblique tube worm disease, white-headed white-mouth disease and bubble disease in the summer flower stage, focusing on Shenyang and Liaoyang aquaculture areas; silver carp, catfish, yellow jaw fish summer flower stage is very prone to ciliate disease, focusing on Shenyang and Liaoyang aquaculture areas.
(3) Grass carp: prone to gill rot, enteritis, complications of red skin disease, and wheelworm disease. Focus on the main breeding areas of Shenyang and Liaoyang.
(4) Turbot: prone to enteritis, red-billed disease, and bacterial rotten fin disease. Focus on the factory breeding area of Huludao.
(5) Rainbow trout: parasitic diseases such as small melon worm disease, three generations of insect disease, and bacterial diseases such as gill rot and enteritis disease are prone to occur. Focus on Huludao, Benxi, Dandong, Liaoyang aquaculture areas.
(6) River crab: prone to molting disease and edema disease. Focus on Panjin, Anshan rice paddies and reed field breeding areas.
(7) Loach: prone to water mold disease, focusing on the high-density breeding area of Panjin loach.
(8) Sea cucumber: prone to rotting disease. Focus on all coastal farming areas.
(9) Chinese shrimp, Penaeus vannamei: prone to leukoplakia syndrome and erythematosis. Key coastal aquaculture areas.
(10) Jellyfish: prone to flat head, long neck, atrophy, hanging disease and other diseases. Focus on Dandong aquaculture area.
Suggestions: First, strengthen water quality management, regularly change water, inject water, disinfect, maintain a good water environment; second, ensure the quality of bait. At the same time, it is necessary to find abnormal conditions in time, and do a good job of regulating water quality, sterilization, and bottoming out in advance for various symptoms to prevent diseases. The third is to pay attention to weather changes. According to the forecast of the Liaoning Meteorological Bureau, the precipitation in the province in the summer (June-August) is 461-503mm, which is 10%-20% more than the usual year (418.8mm), of which Dalian, Yingkou and Huludao areas are 10%-20%, Fushun and Tieling areas are more than 20%, and other areas are more than 10%." The average temperature in the province is 23.4-23.9 degrees, which is 0.5-1.0 degrees higher than the usual (22.9 degrees).
(1) Parasitic diseases: grasp the reasonable stocking density, keep the water quality clean, regularly open the aeration equipment, such as encountering sweltering hot weather, the oxygenation time should be extended. Regularly disinfect and regulate water quality with quicklime, bleach powder, biological agents, etc. The whole pool is sprinkled with the corresponding drugs (insecticides) for prevention.
(2) Myxosporosis of freshwater fish summer flower fry: first, when the water temperature is above 15 degrees, the cultivated water body is inoculated with beneficial bacteria in time to control the balance of beneficial algae phases and improve immunity; the second is to adopt soil pond slope protection measures to cut off the infection route of the intermediate host; the third is to feed dikjuli in the unprotected soil pond for prevention and control.
(3) Ciliate disease in the summer flower stage of snakehead, catfish and yellowtail: mainly based on the prevention and control of copper sulfate or traditional Chinese medicine preparations, and 2 intervals of drug sprinkling, 0.75ppm in the morning and afternoon.
(4) Rainbow trout rotten gill disease and enteritis disease: maintain a reasonable stocking density, clean aquaculture water, feeding nutritious and fresh bait. Regularly disinfect production tools and fish ponds; clean the ponds frequently to keep the breeding environment clean and reduce pathogen reproduction; and can also be fed with allicin in the ratio of 3 grams/kg to prevent the occurrence of diseases.
(5) White-headed white-billed and bubble disease of freshwater fish summer flower fry: In the pond under the water splash for about 15 days, the whole pond is sprinkled with chlorine preparation national standard fishing medicine 1-2 times, which can prevent the white-headed white-mouth disease of the summer flower fry; after 10 days under the water splash pond, the whole pond is sprinkled with water quality improver once, which can prevent the bubble disease of the summer flower fish fry.
(6) Turbot enteritis, red-billed disease and bacterial rotten fin disease: strengthen the management of aquaculture water quality, ensure the oxygen content of water bodies, and maintain a good breeding environment; strengthen feeding, scientific feeding of high-quality bait (fresh and miscellaneous fish should be disinfected), enhance the disease resistance of fish bodies, and prevent the occurrence of diseases.
(7) Shrimp leukoplakia syndrome and erythrosis: shrimp ponds should be filled with water before the arrival of the high temperature period, change water as little as possible, and avoid the entry of harmful microorganisms and viruses; strictly prohibit large-scale irrigation to avoid stress reactions to shrimp and cause diseases; regularly disinfect the water bodies of shrimp ponds.
(8) Sea cucumber: pay attention to controlling the breeding density, maintaining good water quality and substrate environment; regularly disinfecting water bodies; regularly improving water quality; pay attention to the change in salinity of the pond water caused by rainfall, maintain an appropriate amount of oxygenation, and prevent too much change in temperature and salinity, causing sea cucumber skin.
(9) Jellyfish: Maintaining an adequate amount of bait is the key to prevent jellyfish with flat heads and long necks.
(10) River crab: For the disease of shelling failure, it is necessary to regularly sprinkle quicklime throughout the whole pond to keep the pool water weakly alkaline. The second is to supplement nutrition, add an appropriate amount of deforatin and shell powder, bone meal, eggshell powder, fishmeal and other mineral-rich substances to the feed. The third is to create a suitable shelling environment to keep the water body relatively stable and the water temperature is 19-28 degrees. River crab edema disease should be changed frequently, keep the water fresh, in the breeding process to be careful to operate, do not cause crab body abdomen injury, can also be 1 mg / l bleach powder or 0.3 mg / l bromochlorohydantoin whole pool sprinkled. (Source: Liaoning Provincial Aquatic Technology Promotion Station)