JP3306174B2 - How to control parasites on marine animals - 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 controlling parasites found on aquatic animals, such as when culturing aquatic animals.

[0002]

2. Description of the Related Art As the fishery production in Japan falls below 10 million tons, the proportion of aquaculture and marine animals increases every year.
It has become an indispensable existence. However, on the other hand, diseases are diversifying due to increased production of multiple fish species, imported seeds and seedlings from abroad, and eutrophication of aquaculture water areas, but also infectious diseases of viruses and bacteria as well as parasitic organisms that cause them. The damage caused by the disaster has been enormous. Conventionally, as a countermeasure, only a chemical bath using formalin, copper sulfate, potassium permanganate, hydrogen peroxide, methylene blue, an organic phosphorus agent or the like has been implemented.

[0003] However, the chemicals used in this chemical bath are highly toxic and have many adverse effects on fish and the like.
Poor prognosis is often accepted.
In addition, it adversely affects food hygiene, environmental pollution, and other cultured products such as shellfish in the vicinity. Some types of parasites have become resistant and have lost or reduced their efficacy. Also, for some parasites, for example, heterobotulium, which infests pufferfish, no effective control measures have been found by nature.

Conventionally, especially in marine aquaculture, fishing net antifouling agents such as tributyltin are mainly mixed with various paints, applied to fishing nets, and used to control algae and shellfish attached to fishing nets. To prevent the attachment of parasitoid eggs such as flukes, and furthermore, the active ingredient suppresses the occurrence of larvae and an intermediate host for certain parasites, for example,
Although it prevented the adhesion of cracks and the like, its use was completely restricted due to problems in marine pollution and food hygiene. Since then, no particularly effective fishing net antifouling agents have been developed, despite the marked increase in occurrence of parasitosis.

[0005]

SUMMARY OF THE INVENTION The present inventors have screened a number of known low-toxicity chemicals, natural products, and their components in a cross-over dipping method against various parasites by screening, and an oral method. As a result of repeated tests of administration methods, etc., it was found that cinnamaldehyde (cinnamaldehyde) is effective, and cinnamaldehyde is soluble in only a small amount in water, but its dilute aqueous solution works well on parasitic organisms. And found that the present invention is extremely valuable for its practical use.

The present invention relates to a method for producing cinnamic aldehyde
When the support material is placed in a water area,
The supporting material supported so as to be eluted is cultured in aquaculture
Cinnamon bark placed in water and gradually eluted from the carrier into the water
Characterizes aldehydes acting on parasites
This is a method for controlling organisms that are parasitic on marine animals .

[0007] Cinnamic aldehyde is almost industrially synthesized at present, and is oily at room temperature, soluble only in a very small amount in water, used as a flavor, and has an LD50 (after 24 hours) in subcutaneous injection on the back of mice. 7.15mg / 10g
And its toxicity is extremely low.

Further, cinnamon oil may be used as the cinnamaldehyde. Cinnamon oil is a genus of camphor (Cinamom)
um), such as C. zelanicum, C. cassia, C. loureirii, and the like, depending on the type of plant, depending on the type of plant, stem bark, branches and leaves, and root bark. Etc. are collected and steam-distilled to obtain 70-90% of cinnamic aldehyde.
contains.

As the carrier, cinnamaldehyde can be supported in an open manner, that is, cinnamaldehyde is brought into contact with surrounding water in water such as a pond, swamp, river, or sea where the carrier is disposed. What can be carried so as to be eluted is used.

The cinnamaldehyde is supported on the carrier by, for example, coating or impregnating on the carrier or mixing with the carrier. Coating and impregnating cinnamaldehyde,
If necessary, after diluting with a diluent such as a liquid polyamide resin, it can be applied to a carrier or by immersing the carrier in cinnamic aldehyde or a diluent thereof and drying.

The carrier may be an inorganic material or an organic material.
It may be plates, rods and molded materials formed into various shapes, and may be made of fibrous materials such as ropes, cords, nets, and for example, pumice, coral, zeolites,
An inorganic porous material such as activated carbon, or an organic porous material such as an open-cell foam of a synthetic polymer such as polyamide, polyurethane and polyvinyl alcohol may be used.

The thus obtained cinnamaldehyde-containing support material is placed in water in which parasites are or may occur. For example, if the supporting material is a net, it is preferable to surround the farmed animal with the net, and in the case of a rope, a cord, or a plate tied in an interdigitated shape, it is preferable to suspend the animal in the culture water area. In the case of a porous material, if it is a small lump, it can be similarly suspended by taking a method such as wrapping it with a net.

Cinnamaldehyde in solid materials elutes in water, albeit in very small quantities. Thus, for example, in the case of parasites, a small amount of this dissolved active ingredient always affects the development of larvae from fluke eggs and the like attached to fishing nets and the like.
It is not known when the larvae will occur,
A small amount must always be contained somewhere in the seawater. Since cinnamaldehyde is effective against each grown parasite, larvae having immature cells and tissues are relatively easily affected. Suppressing larval development ensures that the absolute number of parasites is reduced and that the parasites themselves will always be completely controlled.
In addition, many larvae (Oncomirachidium) swim freely with cilia, and parasitism is established only when associated with a specific host of the parasite. If the larva cannot reach the host, it will die in about half a day. Therefore, according to the present invention, the drug can always be present in seawater, so that the chance of the larvae to associate with the larvae is further reduced, and as a result, the infestation can be completely prevented or the infestation rate can be significantly reduced. This means
The same applies not only to larvae, but also to grown larvae and adults, and also to parasites other than fluke, and the control material of the present invention can be effectively applied to control aquatic bacteria and various pathogenic bacteria. .

The parasites that are the subject of the present invention include parasites from protozoa to metazoans, aquatic bacteria and various pathogenic bacteria, and are exemplified as follows. In protozoa, the ciliates Trichodina (Trich)
odina sp), kilodonella (Chilodone)
lla sp), white point insect (Ichthyophithi)
rius sp and Cryptocaryons
p), Scuticociliatid
a). Ichthyobodo sp of flagellates (Flagella) and the like.

[0015] In metazoans, flatworms (Plastel)
minthes) (Monogene)
nea), Heteraxine, Bivagina, Heteroboturium (He)
terobothrium), Benedenia (Bened)
enia), Gyrodactylus
s), Dactylogyrus or Pseudodactylus
logyrus), Lamello Discus (Lamello)
discus) and other parasites on gills and skin.
In the species of nematodes (Nemathelmnthes), they belong to hookworms (Acanthocephala), and are infested with the intestine.
lum).

The aquatic bacteria include, for example, Saprolegnia, Achly (Achly)
a), Aphanomyces,
Those belonging to a genus such as Fusarium.

[0017] Pathogenic bacteria include, for example, Vibrio and Pasteurell.
a), those belonging to the genus such as Aeromonas, Streptococcus, and Edwardsiella.

The marine animals that host the parasites in the present invention include freshwater and marine animals, and particularly include aquaculture and ornamental animals of all ages, such as fish, crustaceans, and shellfish. In. For example, in freshwater, rainbow trout (Salmo gairdnerii or Oncorhynchus mykis), sweetfish (P
lecoglossus artivelis, eel (Anguillajaponica), carp (Cy)
primus carpio, goldfish, crucian carp (Ca
rassius, tilavia (Oreochromi)
s aureus, coho salmon (Oncorhynch)
us kisch), Pehelay (Odonthes)
tesbonariensis).

In seafood, yellowtail (Seriola)
quinqueradiatae), red sea bream (Pag)
rus major, flounder (Paralichth)
ysolivaceus), Takifugu
u rubripes), Carrot (Caranx d)
elicatissimus, amberjack (Serio)
la purpuraseceus, horse mackerel (Trac)
hurus japonicus, hiramasa (Ser)
iola aureovitttats), Japanese quailfish (Navodan modestus), Ishidai (O
plegnatus fasciatus, swordfish (Oplegnatus punctatu)
s), swordfish (Lethrinus), blackfish (Sparus longispuis), sea bream (E
ynnis japonicus, Suzuki (Lat)
elabax japonicus, Mebaru (Se
basses inermis), Mahata (Epine)
phelus seplemfasciatus, prawns (Penaeus japonicus) and the like.

[0020]

The control material of the present invention controls parasites without damaging cultured animals by gradually releasing cinnamaldehyde in water. In addition, it is possible to remove the parasites on the skin by hanging the control material on, for example, a culture water area and rubbing the control material frequently with animals.

[0021]

The present invention will be further described in the following examples. Example 1 Efficacy test by application to fishing net (field experiment)

Test period May 1 to September 30 Test place Wakayama test fish 2 year old fish of Torafugu (average weight 300g)
1,000 in total Parasitic organisms tested Heterobothrium okamotoi Test subdivision 3m x 3m x 8m nylon fishing nets: 3 test plots, 1 control plot Total 4 water temperature 19 ° C to 28 ° C

Preparation of Test Fishing Nets Test zone fishing nets (A, B, C) A fishing net in which 8 volumes of cinnamaldehyde and 2 volumes of a amide resin (liquid) were applied to the entire surface and dried. Control zone fishing net Fish net coated only with polyamide resin (liquid) * In this case, the coating film component can be oil-based, vinyl-based, epoxy-based, etc. used for ship bottom paint (No. 2).

Test Method Four test subdivisions are prepared at the same tidal current, the same water depth and at a place where they cannot cross each other in the farm, and the test nets A, B and C and the control nets are provided for each subdivision. Was installed respectively. In advance, a group having a high parasitic rate of the insect (3,000
Tail), randomly from test area A containing 25
0 fish, 250 fish for B, 250 fish for C, and 250 fish for the control group were picked and divided into small portions for each test. After the test fish were released to each subdivision, the same feed was fed in the same amount and in the same manner. Test plot A: a plot that was replaced with a new fishing net treated with the reagent once a month during the test period on the first day of each month. Test zone B: A zone where a new fishing net was similarly replaced only once on the middle month of the test period. Test section C: A section in which processing was performed only once at the beginning of the test period, and the net change was not performed until the end. Control plot: untreated, and no net change was performed.

After the end of the test period, on October 1, 10 fish were randomly picked from each section, and the parasitism was examined by microscopic examination at the same time as dissection to judge.

The results are shown in Table I. A clear significant difference was observed in the test plot compared to the control plot. The evaluation in the test plot showed the number of parasites in the order of test plot A <B <C. It was found that the frequency of changing nets increased the control effect. Overall, its effectiveness was demonstrated.

In this test, a five-month test period was established from an academic report that the lifespan of this insect was less than four months (1989, The Society of Fish Diseases of Japan, Ogawa et al.). The rate will change. In particular, the results of past evaluations of fishing net antifouling agents began with the hypothesis that the effect might be exerted at the time of emergence of larvae (Oncomirachidium) from eggs, but the results show that Proven. No findings suspected of toxicity, such as death of fish during the test period, were found.

[0028]

[Table I]

* Larval section: The total number of parasites observed when one piece of the same amount of 10 right and left gill lobes was observed under a microscope. * Adult: The total number of adult parasites in the right and left gill operculum of each of 10 tails.

Embodiment 2 FIG. Removal test for field insects (flukes) (field experiment)

Test period July 1-July 31 Test place Wakayama H farm 2 sample fish Hamachi 2 year old fish (average weight 1,200
g) Parasites to be tested Parasites on the skin Benedenia seriole (protozoa) Test small split 5m × 5m × 8m nylon fishing net 2
Base water temperature 27 ° C Preparation of test net cage Pumice of 3-5 cm in size is wrapped in a bag shape with a small net for fry to be 20 cm wide and purple at 30 cm intervals to form segments. This net basket having a length of 2 to 3 cm is sufficiently immersed in a liquid in which 2 volumes of a polyamide resin is turbid in 8 volumes of cinnamaldehyde and then dried.

Test method: A total of 200 fishes were randomly selected from 2,000 fishes in a group with remarkable parasite infestation and 100 fishes in a test plot and 100 fishes in a control plot. In the test plot, the test net basket was used, and in the control plot, only the resin excluding cinnamaldehyde was used. The net basket which had been immersed and dried was passed through a rope at the center of each small portion and fixed to the rope.
However, the net basket itself was suspended so that it could be rotated in a circle. Each net basket was hung as it was until the end of the test. After the test was completed, 10 fish were picked from each section, and the number of parasites was counted and judged.

Results The results are shown in Table II. The test plot clearly showed an effect of controlling worms. This is not limited to hamachi, but uses the habit of rubbing the body surface of the fish for self-defense, providing a place where the skin can be easily rubbed, and soaking a drug that is effective against worms. Frequently, the fish rub the skin and gradually weaken the insects that have stuck, causing them to fall. Once dropped, the insects die without parasitizing the skin again. Rubbing the skin by the fish makes the skin more likely to be damaged as a side effect, but making the mesh basket movable can prevent this. In addition, the shape at this time may be a float or a rod, and the shape is not limited to a net basket. Conceivable.

[0034]

[Table II]

Test Example Efficacy test against marine bacteria

Test bacteria Saprolegnia sp. Isolated from ayu skin Preparation of Reagents for Two Bacteria One volume of cinnamaldehyde was mixed with 10 volumes of water, heated to boiling and cooled at room temperature, and the resulting supernatant was used as a base drug solution.

Test Method Agar discs having test bacteria A and B cultured on a Sabouraud agar medium plate at 15 ° C. for 48 hours were cut into squares of 1 to 2 mm on a side with a sterile scalpel, and hyphae were attached only to the surface. Is prepared. This was placed on a Sabouraud agar medium plate containing a test agent at a predetermined concentration, and then cultured at 15 ° C. for 48 hours.
C was determined.

Results The MIC for each strain was: 500 μg / ml B. At 500 μg / ml, A. B. In both cases, a similar inhibitory effect was observed.

[0039]

According to the present invention, there is provided a material for controlling parasites which can be very easily controlled by simply arranging them in the water of the aquaculture water area and which is not likely to contaminate the water area. .

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields investigated (Int. Cl. ⁷ , DB name) A01N 25/08 A01N 35/02 A01N 65/00 A01K 61/00 A23K 1/00 CA (STN) REGISTRY (STN ) JICST file (JOIS)

Claims (6)

(57) [Claims] Claims: 1. A support material in which cinnamaldehyde is supported in a carrier material such that cinnamaldehyde is eluted when the support material is disposed in a water area, and the support material is disposed in water in a culturing water area of a marine animal. A method for controlling parasites in marine animals, comprising causing cinnamaldehyde, which gradually elutes from the water to the waters, to act on the parasites. 2. The control method according to claim 1, wherein the cinnamaldehyde is applied or impregnated on the carrier. 3. The control method according to claim 1, wherein the supporting material is an inorganic or organic molding material, a fibrous material, or a porous material. 4. A parasitism for marine animals, wherein a supporting material supporting cinnamaldehyde is placed in the water of aquaculture water area of marine animals, and cinnamaldehyde, which is gradually eluted from the supporting material, acts on parasites. How to control parasites. 5. The control method according to claim 4, wherein the cinnamaldehyde is applied or impregnated on the supporting material. 6. The control method according to claim 4, wherein the supporting material is an inorganic or organic molding material, a fibrous material, or a porous material.