CATDOLL : CATDOLL: How to detect sporozoites in shrimp fry?

1. How to detect sporozoa in shrimp fry?

For the detection of sporozoa, most of the time, a preliminary judgment can be made with the naked eye based on the large spore cysts on the shrimp fry. If you want to further confirm which type of sporozoa is causing it, you need to observe it under a microscope.

When debugging, start with 400 times observation and finally adjust to high magnification. Make judgments and distinctions based on polar capsules, polar filaments, and iodine bubbles. Sometimes the cysts of sporozoan diseases are very small. Larger ones appear as milky white cysts the size of millet on the body surface and fins, or parasitize in the muscles, causing the shrimp's body surface to be uneven, or with tumor-like protrusions, or parasitize in the muscle fibers, the skull, and the spine. The latter is more difficult to judge, and can be judged by combining whether the shrimp swims abnormally in the water and whether it is emaciated.

2. What does it mean if the belly of a crayfish is white?

Today, I flipped through several books on crayfish farming and finally found the cause of the white belly of crayfish: microsporidiosis.

I believe that many crayfish farmers have never heard of "microsporidiosis". I only learned about it after checking books, so I will explain it briefly to you here, and I hope it will be helpful to everyone!

Microsporidiosis:

Cause: Caused by microsporidia.

Symptoms: The muscles of the diseased shrimp turn from red to white, and the tissues are loose and soft. Some diseased shrimps have blue-black pigmentation on their backs and dorsal sides. They can parasitize in the gonads inside the shrimp's cephalothorax, as well as in the smooth muscles of the blood vessels and digestive tract. There is an opaque white area on the midline of the back of the diseased shrimp.

There is currently no cure for microsporidiosis, and we can only strengthen prevention to prevent the occurrence of the disease.

Prevention of this disease:

① Before releasing the shrimp fry, the shrimp pond must be disinfected and cleaned. For shrimp ponds that have been infected with this disease, find some free time to drain the water and dry the pond to kill the bacteria as much as possible.

② The shrimp bodies must be disinfected before the shrimp fry are put into the pond.

③For diseased shrimp ponds, timely disinfection is required. If there are diseased or dead shrimps, they must be promptly removed and buried deeply to prevent the spread of pathogens in the water and cause large-scale infection of crayfish.

④ During the breeding period, the water quality of the shrimp pond must be maintained in good condition. The water must be changed frequently, and the bottom must be disinfected and improved regularly to kill harmful bacteria and adjust the water quality.

Summary: Microsporidiosis is not like other crayfish diseases. This disease can be prevented but not cured, so prevention should be strengthened during the breeding process. First, it is necessary to disinfect and clean the shrimp pond; then, disinfect the crayfish; finally, strengthen management during the breeding period, change the water frequently, disinfect and improve the bottom regularly, and adjust the water quality.

3. What is the treatment plan for spore worm ponds?

1. Thoroughly clean the pond

Before stocking the fry, the pond needs to be thoroughly desilted to remove the surface silt. 150 kg of quicklime per acre of water surface is used for pond desilting. Pond desilting and other measures are essential for the prevention and control of myxosporidiasis. It can kill aquatic oligochaetes (water earthworms) and radiosporidians in the water and bottom mud.

2. It is recommended to take the following products for prevention before the peak period of the disease (before May).

Mix 650 grams of chlorpheniramine hydrochloride + 720 grams of levamisole (calculated at 98% content) with 1 ton of feed and use it continuously for 3-5 days.

3. Scientific and reasonable feeding, regular adjustment and improvement of water quality and bottom environment, use of astragalus polysaccharides, vitamin C and other immune enhancers to feed and enhance the physique of fish can effectively reduce the incidence of myxosporea.

4. In areas where the disease is prevalent or where aquaculture species are being raised, different species can be mixed and the species-changing breeding method can effectively reduce the occurrence of spore diseases. In the main crucian carp production areas, river crabs and shrimps are mixed in crucian carp ponds to feed on water silkworms at the bottom of the ponds, which can effectively reduce the occurrence of spore diseases by reducing the number of intermediate hosts.

4. Can cotton shrimp be eaten?

It is best not to eat it. I think it is best not to eat cotton shrimp, as it does not taste that good.

Cotton shrimp is actually a disease of shrimp. During the breeding process, white substance appears on the shrimp's abdomen. As time goes by, the range of this white substance will become larger, making the entire abdomen of the shrimp appear white and turbid, and the meat is loose, like cotton flocs. This is what farmers often call cotton shrimp.

This disease occurs mainly because the shrimp is infected with microsporidia. Although there will not be a large number of deaths at the beginning, the shrimp's intestines will show symptoms, the intestinal wall will become thinner, and digestion and absorption will be seriously affected. The growth will become slow. When the number of spores increases, they will erode the liver and cause abdominal erosion.

Cotton shrimp can be eaten, but it must be cleaned and steamed at high temperature before it can be eaten