Why did you say that the first shell of the river crab was like passing through the gate of hell?

As the temperature rises gradually, the most difficult shell of the river crab is coming to an end. This year, the first shell of the river crab seems to have passed through the gate of hell.

1. Why did you say that the first shell of the river crab was like passing through the gate of hell?

(1) The weather is high and low, and the temperature difference between day and night is great. In early April, the temperature changed dramatically, and some Eriocheir sinensis just molted in rainy and cold weather, which led to excessive stress response of Eriocheir sinensis, which led to the death of many Eriocheir sinensis soft shells before molting, and the survival rate and turnover rate were seriously affected.

(2) Early culture of Eriocheir sinensis In order to control the growth of aquatic plants, many ponds are in shallow water level culture mode, some ponds have no ring ditches, the overall water level is shallow, and some newly opened ponds have serious water leakage. In addition, many bosses did not make a reasonable plan for the later aquaculture management before the weather changed, and did not raise the water level properly before the weather changed. This series of reasons led to 20 18 crabs molting in a relatively unstable water body.

(3) This year's pests are threatening, and they broke out earlier and more violently than before. Ammonia nitrogen and sub-salt in Tangkou seriously exceeded the standard, and dissolved oxygen was insufficient.

(4) In the early days, many aquaculture friends didn't pay attention to the fertilizer and water work, and the mouth of the pond was too thin. When the weather is bad, the water body is unstable and the anti-stress ability is weak.

(5) The long-standing moss problem.

(6) There is too much grass in the original pond, and the pH value of the water body is high, which seriously stimulates the crab gills and causes the crab to molt late and hard.

(7) The problem of drug residue in Qingtang led to crab poisoning.

Because many ponds use large doses of trichlorfon to kill trichlorfon when cleaning ponds, and many newly opened ponds have pesticide residues, the sediment has a strong adsorption to diphacinone and pesticides, and diphacinone and pesticide residues will volatilize into the water body with the increase of temperature, and many friends improperly choose detoxification drugs, resulting in a large number of drug residues in the water body.

What shall we do after a shell?

(1) Disinfect the water body, kill harmful bacteria in the water body, and deal with the problems of untreated crustacean ulcer and claw grinding caused by molting in the early stage.

(2) Dealing with moss problem

(3) Dealing with bugs

There are too many insects at the mouth of the pond, which leads to mixed water. After molting, you can choose Yanbian to kill insects in sunny morning, and then give water to detoxify and fertilize in time.

(4) Dealing with the problem of too much grass and too thick grass.

(5) Treatment of drug residues in clear soup.

(6) If a shell has a large number of dead ponds, it is suggested to replant seedlings according to their own dead ponds to avoid insufficient yield and reduce losses. Supplementary seedlings should be selected with appropriate size, neat specifications, sound limbs and no disease.