Common problems and prevention and control points of shrimp culture in hot weather
High temperature and heat is the peak of disease in aquaculture
From June to September of each year, the temperature is usually the highest in the year. At this time, shrimp farming has entered the peak production season. In the high temperature season, the weather is hot, the light is strong, the water temperature is high, the water is rainy, and the water quality is changeable. Not only do all kinds of bacteria breed in large numbers, but they also affect the feeding and molting growth of prawns, which is easy to cause disease and death. Typhoons also occur frequently in summer, which is the peak of disease occurrence in aquaculture. In the hot season, what diseases and problems will appear in shrimp farming? Let's see with Xiao Nuo!
Problems in shrimp culture under high temperature and heat
Vibrio products recognized by most shrimp farmers
1. High temperature: The temperature often exceeds 32 ℃, and the temperature of shrimp ponds with shallow water level is close to or even exceeds the temperature. It is also very common for the temperature to exceed 36 ℃.
2. Accelerated water metabolism, variable water quality: high temperature, accelerated water metabolism cycle, should be a good thing. However, the life cycle of algae and flora will also be shortened, which will affect the metabolic cycle of water body instead. In addition, it is rainy in summer, the temperature and water temperature are changeable, which is prone to sudden changes in salinity, low pH or pantothenic acid.
3. The water body is changeable, and prawns are easy to be sub healthy:
① High temperature weather will increase the water temperature, and high water temperature will also increase the bottom temperature, which is easy to cause bacteria (such as vibrio) and viruses to multiply in large quantities;
② Algae reproduce in large numbers (including cyanobacteria), forming a dominant population that is too thick and prone to toxins and algae fall;
③ The feces of residual bait are easy to corrupt;
④ During the high temperature period, the water body is prone to temperature stratification, which hinders the exchange of upper and lower water bodies, and the surface highly dissolved oxygen water body cannot enter the bottom. The tank bottom is easy to be anoxic and generate bottom odor and bottom heat;
⑤ Increase of ammonia nitrogen, nitrite, hydrogen sulfide and other toxic and harmful substances;
⑥ The high temperature period is also the typhoon prone season. The water body is easy to be stratified in typhoon weather, and the water quality indicators change seriously.
In a word, the high temperature period is conducive to the reproduction of various organisms (zooplankton, plants, microorganisms and cultured animals), and also brings more unstable factors. At this time, a certain factor changes, and the corresponding diseases such as inverted algae, white stool, jejunum and jejunum atrophy, white spot, blue algae, etc. will easily occur.
And farming is like driving. The most important thing is to reach the destination safely. The goal of farming is to cultivate safely. Then how can we ensure the healthy and vigorous growth of prawns in the hot season? Xiao Nuo believes that scientific management and prevention are the key.
Several common problems and prevention and control suggestions in high temperature season
Vibrio products recognized by most shrimp farmers
（1） Poured algae:
Inverted algae is a phenomenon that a large number of algae in the aquaculture water body die, causing the water color to suddenly become clear, turbid (yellow, white and pink green), or even red.
1. Changes in water body (physical and chemical factors) when "algae fall" occurs: firstly, dissolved oxygen will decrease, while carbon dioxide will increase: due to the death of algae, photosynthesis will be weakened, the decomposition of a large number of dead algae will also consume a large amount of oxygen, and the increase of carbon dioxide will rapidly reduce the pH value; Secondly, ammonia nitrogen and nitrite increase: a large number of dead algae decompose, which will increase the oxygen consumption, and also produce a large amount of ammonia nitrogen and nitrite; Third, protozoa in water will multiply in large numbers, which in turn will inhibit the growth of algae. Fourth, due to the lack of sedimentation of algae, the suspended solids (fine dust, feces, dead algae, etc.) in the water become turbid.
2. Reasons for algae falling: sudden change of weather, imbalance of aquatic organisms or improper management. Improper management includes bad timing of fertilization and supplement, excessive fertilizer and water at high temperature, improper drainage and replacement of water, and excessive use of disinfectants.
Prevention programme
Recommended use: Junba+Shuilishuang+Bottom sulfur light
① Timely supplement of carbon and microelements: Nutrients can be properly supplemented by Norris product Algopeptide Mong or Junba in time to maintain the growth of algal cells to maintain the stability of water quality, and EM bacteria (Junba, Junbao, Miracle King, etc.) can be used for auxiliary water regulation.
② Open more oxygen machines (prevent water stratification).
③ Sprinkle heat clearing and detoxifying drugs regularly.
Recommended treatment measures:
① Detoxification: You can use Norris High Efficiency Detoxification Treasure or Shuilishang to adjust and stabilize the water quality;
② Anti stress: high stable VC and bio health can be used for anti stress work;
③ Bottom modification: the bottom can be modified with products such as enzymolysis bottom modification and bottom sulfur light products;
④ Algae introduction: fresh water added with algae species.
⑤ Algae culture: select appropriate fertilizer and aquatic products according to water quality and weather conditions for algae culture.
White stool
1. Symptoms: shrimp feces are discharged from the body with intestinal mucosa, mainly due to hepatopancreas digestion and intestinal infection. Usually, a large amount of white stool can be seen at the tail of the shrimp pond (white stool is thin, sticky, floating on the water); The shrimp feed slows down, the jejunum empties the stomach, and the shrimp swim in the pond. After a few days, they begin to die secretly or die in large numbers, leading to pond discharge.
2. Reasons: In hot weather, the algae is too thick and the algal toxin is increased. In addition, the shrimp ingested feed with high nutrition (such as high protein) or unbalanced nutrition, which led to atrophy of the liver and pancreas, impaired digestion and absorption of the intestine and stomach, leading to intestinal swelling, then atrophy, thinning, segmentation, and then jejunum and stomach, swimming in the pond, leading to death.
Prevention programme
Recommended use: Zhenling+Ganlijian+Changlijian
① Zhenheling: It can prevent enteritis, remove white stool, promote the proliferation of beneficial bacteria in the intestinal tract, and significantly improve the defecation, loose stool, white stool, intestinal disconnection and other phenomena of aquatic animals.
② Liver building health: comprehensively improve the detoxification and detoxification functions of aquatic animals, care for the health of liver and tissues, and cooperate with appropriate disease drugs to quickly eliminate the toxic and side effects of drugs, enhance the efficacy of drugs by 7-10 times, and shorten the recovery time by 50% - 60%.
③ Changlijian: Improve intestinal health in 24 hours! Prevent and control enteritis and white stool, regulate the balance of intestinal flora, improve the immune function of animals, and effectively reduce the occurrence of enteritis and other diseases.
Hepatic atrophy of jejunum and jejunum caused by vibrio parahaemolyticus
1. Symptoms: A small amount of prawns eat or do not eat. The intestines and stomach are empty and there is no food, which is light yellow. The hepatopancreas is obviously atrophied, which is only one third of the normal size in severe cases. The diseased prawns rarely swim on the water surface, often lie on the side of the pool, with weak vitality, and there is sand raking phenomenon in the Nitang.
2. Cause: The continuous high temperature causes the water to become thick and green, the algal toxins to strengthen, damage the liver of the shrimp, and reduce the resistance of the shrimp; The concentration of Vibrio thermophilus in bottom odor increased sharply with the increase of feed feeding and feces of residual bait;
Prevention programme
Recommended use: Arc Hunting Agent 3+Arc Hunting Agent 4
The latest generation of bacteriophages can rapidly lyse the harmful bacteria of Vibrio parahaemolyticus, which is safe and efficient.
（1） Cyanobacteria:
Blue algae are suitable for growth and reproduction in the environment of high temperature, high nitrogen and low salt. The aquaculture water body is eutrophic, the water is not changed frequently, and the water body containing more organic phosphorus is prone to cyanobacteria.
Harm of cyanobacteria:
① Inhibiting the growth of other algae, resulting in insufficient dissolved oxygen at night;
② The pH value is too high, leading to chronic alkalosis of shrimp;
③ Cyanotoxin can cause fish and shrimp poisoning and death;
④ It is difficult for prawns to digest blue-green algae, and they are prone to enteritis.
Prevention programme
Recommended use: Lanjing, live enzyme, Junbao
① According to the conditions, the water should be changed properly. Before changing the water, it is better to detect and eliminate the water source containing cyanobacteria species, so as to avoid pumping cyanobacteria species when changing the water.
② Maintain the original beneficial algal colony advantage, improve the sediment and control the growth of cyanobacteria by supplementing living bacteria.
③ The practice shows that the regular use of compound lactic acid bacteria has a good inhibitory effect on cyanobacteria.
④ Once it is found that the water body tends to be blue and green, it is necessary to change the water in time and use products containing sodium humate and compound spores for continuous regulation, so as to strengthen oxygen enrichment in the process.
Viral leukoplakia
1. Symptoms: At the beginning of the disease, white spots can be seen on the shell of the diseased shrimp, most of which are in the head and chest, followed by the abdomen. Sometimes there are also white spots at the end of the fallopian tube. At the later stage, the white spots turn to black spots. The diseased shrimp swim alone, and their swimming power is weakened until they die.
2. Cause: high temperature and rainstorm, sharp drop in water temperature, triggering the outbreak of white spot virus, etc.
Prevention programme
Recommended use: immune multiantibody+Zhenling+special immune globulin
Use of immune multiantibody water sprinkling, Zhenling and immune globulin mixture
① Before rain: regularly sprinkle calcium and magnesium containing products, stabilize water and replenish calcium (Norris nanocrystals or AD calcium oxide products can be used to rapidly replenish calcium and trace elements)
② In the rain: use vitamin C containing phosphate products to do a good job in shrimp protection and anti stress, and it is recommended to use Shanghai Norris High Stability VC
③ After rain: After high temperature and rainstorm, use mild disinfectants to disinfect in time to prevent bacteria from breeding after rain. It is recommended to use Norikwick Shanghai for pond disinfection.
④ Oral administration: At the same time, take orally lactic acid bacteria, mannan oligosaccharides and other beneficial intestinal health substances to protect the liver and intestines.
In addition, in order to reduce the burden of prawn hepatopancreas and reduce the accumulation of organic matter in the water and bottom sewage after entering the hot weather, it is recommended to properly control the feeding (control the feeding time of prawn) and stop feeding one meal a week.
reminder:
In hot weather, fish and shrimp will also have different symptoms due to the environment, water quality, food and other factors. If you are unable to identify the situation or have doubts about the use of Norris products, you can call the official telephone of Norris or leave a message on the WeChat public platform to thank everyone for their trust and support in Shanghai.
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