Why can't shrimp farmers breed on a large scale?

1. Weather: Continuous low temperature and rainy weather, farmers replant seedlings 8-9 times, and the more they replenish, the worse they get.

In a normal year, May in the north, the temperature around the long summer should be about 20 degrees at night and 30 degrees at noon, which is already suitable for planting seedlings. Most farmers also choose to release seedlings at this time, but this year, the climate is abnormal, and the continuous low temperature and rainy weather will cause most of the released seedlings to freeze to death. The rest will also become weak seedlings, which will be difficult to reproduce in the future. Coupled with the reason of replanting seedlings, the vast majority of farmers do not have the economic strength to buy high-quality seedlings again. Some farmers are greedy for small and cheap, so they choose to find the original seedling manufacturer and ask for a part for free or buy a part at a low price. Driven by interests, those nursery farms will never give high-quality shrimp seedlings to farmers. To take a step back, even if you have the money to supplement high-quality shrimp seedlings, you can't estimate the number of shrimp seedlings left in the pond, either more or less. And the rest of the shrimp seedlings are already weak seedlings. Therefore, these farmers directly lost at the starting line.

At this time, friends who have not released seedlings will choose to wait and see until the temperature rises. However, new problems have come again. The water transfer in the pond has been completed, and the seedlings are ready to be released around this time. The seedlings can't be released, but the water system will change normally. When the temperature rises, it is no longer suitable for seedling release, and normal seedling release becomes compulsory seedling release.

Another reason is that some nursery work in nursery places is also completed around this time point. It's time to get out. It's impossible. The nursery pond can't bear the metabolism of many shrimp seedlings because of overload. Miao Chang will not sit idly by, and hard-earned money will be wasted. They will tide over the difficulties by controlling materials, changing water vigorously or using illegal drugs. What can't be done can only be lost. There are also some seedling farms where shrimp seedlings are discharged, which is euphemistically called "better discharge, not harming farmers". In fact, it is really impossible to cross. The high-quality seedlings that can barely survive have also become weak or sick seedlings. So when you look at shrimp seedlings in the nursery, you will find white seedlings, shrimp seedlings with different colors, and shrimp seedlings with half stomach and half jejunum. At this time, the seedling farm is in a hurry, and if it is not sold, it will die. Shrimp farmers are in a hurry. If they don't release the seedlings, they won't release them. So as soon as the weather improves, we will grab the seedlings immediately. And this kind of shrimp seedlings, put in a pond that is not suitable for them, the consequences can be imagined.

By the time of the second batch of shrimp seedlings, most seedling farms no longer cultivate high-quality seedlings, but mostly second-generation or original seedlings. At this time, because there is no market for the first batch of seedlings, there will be a second batch of seedlings, which will be in short supply, leading to the scramble for seedlings all the way, and sick seedlings, weak seedlings and immature shrimp seedlings will enter the market. Then there is a vicious circle, and then replant seedlings. In some ponds, seedlings can even be replanted eight or nine times until the end of June. The later, the worse the quality of shrimp seedlings. This also determines the tragic ending of most farmers.

Second, shrimp seedlings: "iron seedlings" that don't grow up, or infected with germs when raising seedlings.

For the reason why shrimp don't grow up, most farmers will think it's the fry. I personally don't think so. Genetic reasons are of course important, but have you ever thought about breeding friends? In any nursery, 100 prawns will not be selected as cultured prawns. Inbreeding is possible, but it will only cause weak seedlings, and it is extremely impossible to cause iron seedlings.

I think the main reasons can be divided into two points.

The first point is that shrimp seedlings are infected with some germs (not several seed farms near the same area, it is estimated that the water source carries germs), parasites, or illegal drugs. The technical ability of the technician in the seedling farm is uneven, and his habit of using a certain drug may also be that the quality of the drug he is used to is unstable, and the amount of experience has different results. This is what I always say. The side effect of success lies in thinking that this year's experience is also suitable for next year. So it caused a stiff seedling.

The second point is that the liver is always in a sub-health state during the breeding process. The imbalance of water system causes some toxins to be too high, feed ratio, some trace elements to be lacking, and some Chinese and western medicines are habitually mixed, which affects the absorption and utilization of various trace elements.

Third, the liver-nourishing stage: farmers can't control the feeding amount in the "liver-changing stage"

You can also change the name, called the transition period. That is, the liver transition period of shrimp from eating the feed of larvae to eating the feed of adults. These two kinds of feed are completely different, almost worlds apart. In a short time, the liver is difficult to adapt. This period requires all adjustments to be made around the successful transformation of the liver. Observe prawns carefully, and do not feed them in large quantities before the liver has been successfully transformed. However, many farmers, unaware of this layer, often appear and begin to die within a few days of formal feeding. The light ones will start to die at 80 to 150, and the serious ones will almost die. The breeder is at a loss, but he can't find the reason. The fundamental reason is that they have not done well in this transitional period. Others are afraid to feed because of fear, which leads to malnutrition and stunting. Shrimp eats a lot of dead algae in sediment because of lack of food, which causes liver and intestinal diseases.

Fourth, medication: the misuse of "deified" drugs and their side effects.

In the market, there are many kinds of drugs used in shrimp ponds. So far, I haven't found any drugs with side effects. Excessive and unrealistic propaganda even myths the functions of some drugs. What is even more hateful is that it is clearly a medicine, but it is marked as a health care product. Not a word about its side effects. A friend joked that shrimp did not die of illness, but died of medicine. For example, in the matter of mixing materials, I mistakenly believe in the propaganda of mixing materials in the whole process with both Chinese and western medicines. I didn't know that all therapeutic drugs were toxic. Long-term mixed administration and oral administration will cause different degrees of liver damage. Lighter people will cause the degradation and dependence of the immune system and destroy the absorption and utilization of some nutrients. In severe cases, it directly leads to liver failure, and dead shrimp.

There are also some bad manufacturers that produce fake and shoddy products. When a single drug is used, the side effects may be relatively small. When several drugs are used together, the side effects may accumulate, which may be toxic. This has yet to be confirmed. This also explains why the more treatment, the faster the death. That is, farmers, whether shrimp should be treated after it is ill has always been the focus of debate. Often shrimp will heal, so it's better to leave it alone. To put it simply, the use of detoxification products can be divided into acidic and alkaline, and its acidic antidote is forbidden to be used in ponds with low alkalinity and low salt content; Its alkaline antidote is forbidden to be used in ponds with high alkalinity and high ammonia nitrogen. The more detoxification, the greater the toxicity. This is basic common sense. But to be honest, few shrimp farmers know. I haven't seen it either. It's on the drug instructions of any manufacturer. For another example, VC class is extremely unstable; Bacterial preparations, affected by pH, will compete for oxygen to kill shrimp under the condition of bottom oxygen, as well as bottom modification, disinfection, trace elements, calcium and magnesium, etc., so I won't list them one by one.

5. Eutrophication: harmful algae are easy to break out, and once out of control, they will be unable to return to the sky.

With the extension of aquaculture years, the accumulation of silt at the bottom of the pond, other aquaculture wastewater, domestic sewage, agricultural wastewater, etc. , a series of pollution, leading to eutrophication of water sources. In this environment, harmful algae will erupt on a large scale and many times, and other systems will change accordingly. Resulting in slow nitrogen circulation. Shrimp ponds belong to high-speed nitrogen circulation system. However, farmers did not realize the stakes, did not fully consume excess nutrients before releasing seedlings, and did not establish a system suitable for high-speed nitrogen circulation in shrimp ponds in the future. No sooner had a small amount of feed been put into the pool than the water got out of control. There's nothing we can do about it.

The intransitive verb Vibrio: makes prawns sick and stimulates the outbreak and spread of parasites.

In other words, pathogenic bacteria. There are many kinds of bacterial diseases, but Vibrio is the main cause of harm. Vibrio can not only make prawns sick, but also stimulate the outbreak and spread of parasites. Once out of control, it means the end of farming. Personally, I think the reason of Vibrio flooding is nothing more than system imbalance. There are many reasons for the imbalance of the system, such as the weather, adjustment errors in a certain link, medication errors, blind disinfection, etc ... This article does not describe how to adjust the system.

Seven, the wrong idea: shrimp depends on luck.

Shrimp farmers who can comprehensively understand and systematically cultivate concepts are rare. So some shrimp farmers simply rely on good resources and make money by luck. It is claimed that shrimp farming is blind farming and never accepts learning and scientific and systematic farming techniques. These people, who have good resources, simply breed with high consumption resources and have a chance of success. Earn a little money and get carried away. But once there are other changes in resources, it is the lamb to be slaughtered. Luck is unreliable after all.