JPH0751029B2 - How to treat shrimp's bollworm disease - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for treating shrub shrimp, which causes death due to the attachment of pathogens such as Vorticella to shrimp shells, legs, swimming legs, caudal fins, gills and mustaches.

[0002]

2. Description of the Related Art In recent years, shrimp aquaculture has become more and more popular, but when a large number of shrimp die due to infectious diseases caused by harmful microorganisms due to organic matter contamination due to overfeeding or lack of dissolved oxygen. There is. As a source microorganism of infectious diseases, pathogens of the family Vorticella, which is a kind of ciliates, have recently been recognized, and the increase of infectious diseases to which shrimps attach to these ciliates has become a serious problem. The disease first occurs in large amounts in the aquaculture ponds such as Vorticella, which attach to shrimp shells, legs, swimming legs, caudal fins, gills and mustaches. At first, it shows a cotton shape, but then the shrimp looks rough and loses its luster. Also, when touched, it feels sticky and dirty, and the symptoms such as the legs and beards being torn off and the tip turning black are exhibited. Furthermore, when this pathogen invades the gills, black or yellow mud-like foreign matters will be attached to the gills surface, and in serious cases, they will proliferate in the gills epithelial cells and locally destroy the cells, It inhibits the gas exchange function of gills. Then, the vitality of the shrimp gradually decreased as the amount of the attached Vorticella increased, and they gathered near the wall of the aquaculture pond and the appetite gradually decreased,
There is a problem that other diseases are more likely to occur, and when the amount of dissolved oxygen in the aquaculture pond is extremely small, mass death occurs.

[0003] Conventionally, when a large amount of pathogens attach to shrimp in this way, a large amount of water in the aquaculture pond is used to promote molting, and in the case of serious infection, tea lees ( 1
Treatment with 10 to 15 ppm (containing 0% saponin) promoted molting of shrimp and also performed water exchange to wash away pathogens in the pond. If the infection is more severe or the shrimp is growing, formalin 25 to 30 ppm (1 if shrimp is small)
The chemical bath treatment was carried out for 1 day at about 5 to 20 ppm), and further the chemical bath treatment was carried out at 0.1 to 1 ppm of a quaternary amine disinfectant such as benzalkonium chloride (active ingredient 50%).

[0004]

However, the treatment method using a highly toxic agent such as formalin and a quaternary amine disinfectant described above is dangerous to the shrimp itself and humans who eat the shrimp, and the water exchange When carrying out, there is a problem that these highly toxic drugs are also washed away and cause pollution problems.

Therefore, the present invention is a safe method for shrimps, humans and other animals and plants without using highly toxic agents such as formalin and quaternary amine disinfectants, and has a sufficient effect against Vorticella. It provides a therapeutic or preventive method that can be expected.

[0006]

Means for Solving the Problems That is, the present invention focuses on the fact that tannin or tannic acid extracted from a plant in nature has bactericidal properties, and by administering tannin or tannic acid to shrimp, the beetle against shrimp. It is intended to safely and effectively treat or prevent diseases.

As a method for administering tannin or tannic acid to shrimp, for example, a high-concentration tannin or tannic acid solution may be used for a short period of time, or tannin or tannic acid may be directly added to a shrimp culture pond to reduce the concentration. There is a method of culturing shrimp in the solution of. The medicinal bath is effective for juvenile shrimp, and the method of directly adding it to the aquaculture pond is effective for adult shrimp.

[0008] Tannin or tannic acid is a substance widely existing in the plant kingdom, and is a general term for compounds that generate polyhydric phenol such as gallic acid by hydrolysis. Chemically, it is classified into hydrolyzed tannin and condensed tannin. The former is Genosho, peony, coffee,
Highly contained in maple, beech, etc. The latter is green tea,
It is often found in persimmons, grapes, keihi, yukinoshita, mimosa, etc. Therefore, since these extracts contain a large amount of tannin or tannic acid, the extract is dissolved in water or the like to prepare a solution having an appropriate concentration. Then, the concentration of tannin or tannic acid in the pond can be adjusted by sprinkling this solution so as to have a predetermined drug concentration according to the size of the pond.

Both the above-mentioned hydrolyzable tannin and condensed tannin are effective against Vorticella vulgaris, but it is necessary to select them depending on the degree of disease and the stage of shrimp development. In particular, those having a molecular weight of 500 to 3000 are considered to be suitable, and the test results show that the condensed tannin has a stable effect.

The fact that tannin or tannic acid exerts a therapeutic or preventive effect on Vorticella vulgaris is probably due to the astringent effect of tannin and tannic acid. This is because the free radical of the polyhydric phenol group possessed by tannin and tannic acid reacts also with protozoa such as Vorticella and destroys its cell wall or binds to a protein to contract the cell.

Among the protozoa, the pathogens of Vorticella vulgaris are ciliates belonging to the order of the limbus (pericardium). Among them, the most common species are genus Vorticella and Calquecium. It is a ciliate belonging to the family Vorticella, but other ciliates belonging to the family Epistyris may also be the pathogens of Vorticella.

As a method for effectively removing the pathogens attached to the shrimp using tannin or tannic acid, the tannin or tannic acid prepared at an appropriate concentration as described above is directly added to the shrimp culture pond, or Alternatively, there is a method of bathing shrimp in a bath of tannin or tannic acid. Specifically, tannin or tannic acid is dissolved in water for 10 to 5
It is carried out by evenly sprinkling the medicine prepared at 0% concentration on the aquaculture pond and the medicinal bath. The amount of input depends on various factors such as the area and water volume of the target aquaculture pond, the growth stage of shrimp, and the amount of shrimp euphoria, but in general, when treating V. bollworm disease once it occurs. When it was sprayed directly on the aquaculture pond, it was about 5 to 20 ppm, and when it was sprayed on the medicinal bath, it was about 10 to 30 ppm. Especially, the effect was seen at a high concentration of 50 ppm in the medicinal bath for a short time of about several minutes.
Moreover, even if it is a very low concentration of about 1 to 2 ppm in the case of preventing Vorticella beetle disease, it will have a favorable effect on the shrimp in the aquaculture pond.

[0013]

[Example 1] [Treatment test for Vinegar shrubs on juvenile shrimp] Venue: Donggang Fisheries Experimental Station, Taiwan Time: April Pond area: 8 square meters Pond depth: 1 m Pond water temperature: 26 ° C Seedlings: grass shrimp (average) Body length: 0.5 cm) Release date: April 25 Release amount: 500,000 species Drug type: 50% concentration solution of mimosa extract Under the above conditions, change the concentration of the administered drug and the bath time. The test was conducted with various changes. The results are shown in Table 1.
In the table, (+) means survival and (-) means death. Confirmation of survival or death was made by observing with a microscope, and the state in which the Vorticella was repeatedly contracting was regarded as alive, and the state in which it did not move was regarded as death. After the observation, the juvenile shrimp were returned to another pond containing no drug and allowed to cultivate, and the growth state thereafter was observed.

[0014]

[Table 1]

[0015]

[Example 2] [Treatment test for weevil disease on juvenile shrimp] Location: Hebei Province, China Time: May Pond area: 25 square meters Pond depth: 1 m Pond water temperature: 24 ° C Seedling: grass shrimp (average length) Release date: May 4th Release amount: 600,000 animals Type of drug: 50% concentration solution of mimosa extract Under the above-mentioned conditions, the concentration of the administered drug and the bathing time can be varied. The test was changed. The results are shown in Table 2.
The means for confirming survival and death is the same as in Example 1 above. After the observation, the animals were kept in another pond.

[0016]

[Table 2]

[0017]

[Example 3] [Treatment test for Vorticella vulgaris disease on adult shrimp] Venue: King's farm in Taiwan Season: May-September Pond area: 1 hectare Pond depth: 1.2 m Pond water exchange rate: 10 % / Day Pond water temperature: 28 ℃ Shrimp species: Grass shrimp Release date: May 15 Release amount: 300,000 types of drug: 50% concentration solution of mimosa extract Under the above conditions, The test was conducted by changing the concentration of the administered drug and the treatment time in the open pond. The results are shown in Table 3. In addition, the means for confirming survival and death is the same as in Example 1
Is the same as. After the observation, the animals were returned to the same pond where the drug was administered, and the subsequent growth state was observed.

[0018]

[Table 3]

According to the above test results, in the case of juvenile shrimp, if the drug concentration is as low as 5 ppm, the protozoa will not be killed even if the drug bath time is prolonged. Moreover, the concentration of the drug is 10ppm to 20pp.
When m is set, the protozoa can be killed without affecting the shrimp seedlings even if the medicinal bath time is extended to some extent. Furthermore, when the concentration of the drug is 30 ppm, it is possible to kill only the protozoa without affecting the shrimp seedlings if the drug bathing time is about 8 hours, but if the drug bathing is longer than that, the shrimp seedlings will also They may die together. However, even when the drug concentration is as high as 50 ppm, if the drug bath time is set to about 5 minutes, only the protozoa can be killed without killing the shrimp seedlings. Moreover, in this case, since the bath time is short, the stress on the shrimp can be minimized. On the other hand, in the case of adult shrimp, the treatment time is long even if the concentration of the drug is as low as about 5 ppm, and thus it effectively acts on the protozoa.

The shrimp seedlings thus treated for weevil disease were then cultivated in other ponds, and the growth was smooth, and the protozoa did not adhere again. Three months after the culturing, Ordinarily, those with a body length of 7 to 8 cm had grown to an average body length of 18 cm. When the adult shrimp were returned to the original pond and allowed to cultivate after the test, there was almost no adverse effect of the drug on the shrimp, and the protozoa grew well without reattachment.

[0021]

As described above, according to the method for treating shrimp's bollworm disease of the present invention, it is widely present in the plant kingdom without using highly toxic agents such as formalin and quaternary amine disinfectants. By using tannin and tannic acid, it is possible to effectively kill pathogens such as Vorticella that attach to shrimp by a very safe method, and prevent the massive death of shrimp due to Vorticella beetle disease. Further, according to this method, the pathogens of the same species do not adhere to the shrimp once treated, and there is also an effect that a smooth growth of the shrimp can be expected. Furthermore, in the case of the present invention, since the wastewater from the aquaculture pond has no toxicity, it does not cause pollution problems due to the wastewater, and is extremely safe not only for shrimp and humans but also for other animals and plants. Also has the effect of purifying drainage channels by the action of tannin and tannic acid.

Claims (3)

[Claims] 1. A method for treating bollworm disease, which comprises administering tannin or tannic acid to shrimp. 2. The method for treating weevil disease according to claim 1, wherein the juvenile shrimp is treated with a high concentration of tannin or tannic acid for a short period of time. 3. The method for treating weevil disease according to claim 1, wherein the adult shrimp is directly released in a low-concentration pond to which tannin or tannic acid has been administered.