JPH1072344A - Vermifuge for cultured fish - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a vermifuge for cultured fishes, capable of controlling parasites such as hadamushi (insects adhered to skins) or eramushi (insects adhered to gills) parasitizing on the cultured fishes, capable of stimulating the growth of the fishes, and further enhancing the commercial values of the cultured fishes. SOLUTION: This vermifuge is adjusted to a pH of 3.0-5.0 with an acid such as citric acid, malic acid, cinnamic acid, itaconic acid, propionic acid or acetic acid, and preferably contains a water-soluble polymer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an agent for controlling parasites on cultured fish.

[0002]

2. Description of the Related Art When a parasite is infested in a cultured fish, such as a puffer fish, a yellowtail, a yellowtail, a Japanese flounder, and the like, growth is inhibited, anorexia is reduced, and the commercial value is reduced. Cordyceps and insects are the main parasites. The damselfly hooks on the skin of fish and eats epithelial cells and pigments of fish. Insects parasitize the gill lobes of fish, and the gills greyish-white due to the direct etiological effect of anemia, resulting in anorexia and weakness. In severe cases, death may occur.

[0003] As measures to eliminate these parasites,
A freshwater bath, a concentrated saltwater bath, and a medicinal bath are used. In this method, fish are picked up and stored in still water. Because freshwater baths are difficult to supply and transport large amounts of freshwater,
It is virtually impossible. Concentrated salt bathing is also not possible due to the high risk of fish becoming dehydrated and the need for large amounts of salt. Therefore, a chemical bath method using formalin is currently employed. However, the method using formalin has the disadvantage that it is capable of extermination of spider worms but cannot exterminate the viper, and also has a problem in that it accumulates in fish by regular formalin treatment and generates off-flavor fish.

[0004] Formalin has a capacity of 1000 per cage per year.
Kg is also used, and a large amount of formalin is discarded into seawater after treatment, which has a great effect on marine fish in nearby fishing grounds. Recently, a large amount of formalin is accumulated in cultured pearl oysters and killed in large quantities. Accidents have also occurred. Formalin irritates mucous membranes such as the respiratory tract, and causes 0.
The presence of 5 mg can be fatal. It is a very dangerous compound for work. Therefore, development of a drug that is safe for the human body, has good degradability in seawater, and can eliminate parasites without residual accumulation has been desired.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a safe and highly effective parasite control agent for cultured fish, which has good degradability in seawater and does not accumulate in marine products. .

[0006]

Means for Solving the Problems As a result of intensive studies to solve the above-mentioned problems, parasites are obtained by immersing cultured fish in seawater adjusted to pH 3.0 to 5.0. We found that we could exterminate insects. Substances that adjust pH include citric acid, malic acid, succinic acid, itaconic acid, gluconic acid, acetic acid, lactic acid, methanesulfonic acid, tartaric acid, fumaric acid, propionic acid, adipic acid, glutaric acid, phytic acid, levulinic acid・ Ascorbic acid ・ erythorbic acid ・ pyruvic acid ・ malonic acid ・ crotonic acid ・ nitric acid ・
Organic acids and inorganic acids such as phosphoric acid, sulfuric acid and hydrochloric acid can be used.
These substances are contained in foods or recognized as food additives, have high safety, and have good degradability in seawater. Also, when the cultured fish is immersed in seawater having a pH of 3.0 to 5.0, if a water-soluble polymer is contained, the condition of the cultured fish during the treatment is very good.
The load on the acid can be reduced. Examples of the water-soluble polymer include, but are not particularly limited to, gelatin, chitosan, methylcellulose, sodium alginate, agar, sodium polyacrylate, and natural viscous components. It is more preferable to perform the treatment while passing air or oxygen.

[0007] As shown in Test 1, by immersing the parasite-attached tiger puffer with a solution adjusted to pH 3.2 using various acids, it is possible to exterminate spider worms within the survival range of the tiger puffer. According to Test 3, when the pH is 2.5 or less, the time for exterminating the spider beetle and the time for killing the puffer fish are the same, and there is no time for extermination. PH6.
If it is 0 or more, it will not be possible to exterminate the spider beetle in three hours. Therefore, by performing the immersion treatment in seawater adjusted to pH 3.0 to pH 5.0, it is possible to exterminate spider beetles without damaging the tiger puffer. Test 4 shows that the present invention can control not only spider beetles but also insects. Also, as shown in Test 5, when the water-soluble polymer was used in combination with an acid, the condition of the fish during the treatment was good, and the fish began to swim immediately after returning to the seawater. Get higher.

(Test 1) 80 l of seawater was put into a 100 l plastic container, and each acid substance was added and mixed so as to have a pH of 3.2. Investigated the time it took to fall off and die. After the treatment for a certain period of time, it was returned to seawater, and the state after 48 hours was observed to investigate the effect on the tofugu. The water temperature during the treatment was 25 ° C. The results are shown in Table 1.

[0009]

[Table 1]

(Test 2) Using two kinds of each acid substance, pH
The adjustment was carried out between 3.0 and 5.0. The results are shown in Table 2.

[0011]

[Table 2]

(Test 3) pH 2.
The test was carried out between 5 and 6.0. The results are shown in Table 3.

[0013]

[Table 3]

(Test 4) 80 l of seawater was put into a 100 l plastic container, and propionic acid was added to adjust the pH to 3.5 and 4.0. And the time to death was investigated. The results are shown in Table 4.

[0015]

[Table 4]

(Test 5) 80 l of seawater was placed in a 100 l plastic container, and the pH was adjusted to 4.5 by adding propionic acid, and then the gelatin was added at 0.01 w / v% or 0.1 w / v.
% And dissolved to prepare 2 samples of the treatment solution. Next, the mixture was adjusted to pH 4.5 by adding propionic acid to prepare a comparative test group. Two cultivated tiger puffer fishes with parasitoids were introduced into these three treatment plots, and the time of extermination of the worms and the state of the tiger puffer fish were observed. The water temperature during the treatment was 25 ° C. The results are shown in Table 5.

[0017]

[Table 5]

[0018]

EFFECT OF THE INVENTION pH 3.0 to 3.0 with acids such as citric acid, malic acid, succinic acid, itaconic acid, propionic acid and acetic acid.
Parasites can be controlled by immersing the cultured fish in seawater adjusted to 5.0.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location A61K 33/20 A61K 33/20 33/42 33/42 47/30 47/30 Z

Claims (3)

[Claims] 1. A parasiticide for cultured fish, which is adjusted to pH 3.0 to 5.0. 2. Citric acid, malic acid, succinic acid, itaconic acid, gluconic acid, acetic acid, lactic acid, methanesulfonic acid, tartaric acid, fumaric acid, propionic acid, adipic acid, glutaric acid, phytic acid, levulinic acid, ascorbic acid・ Erythorbic acid ・ pyruvic acid ・ malonic acid ・ crotonic acid ・ nitric acid ・
The parasiticide according to claim 1, wherein the pH is adjusted using at least one of phosphoric acid, sulfuric acid, and hydrochloric acid. 3. The parasiticidal agent according to claim 1, comprising a water-soluble polymer.