JPH07108858B2 - Drugs for the prevention of fish infectious diseases - Google Patents

Description

Detailed Description of the Invention

[0001]

The present invention relates to an prophylactic agent of infectious diseases of fish, particularly, Streptococcus (Streptococcus), class nodule bacteria (Pasteurella), Edwardsiella bacteria (Edwardsiella)
The present invention relates to a drug that reduces mortality due to fish infection caused by bacteria such as

[0002]

2. Description of the Related Art In fish farms, antibiotics and synthetic antibacterial agents are frequently used as countermeasures against frequent bacterial infections. However, these drugs not only lose their efficacy due to the emergence of resistant bacteria and the multidrug resistance of bacteria, but also have an antibacterial agent remaining in the meat of cultured fish, which poses a food hygiene problem. Therefore, there is a strong demand for a method of reducing mortality due to bacterial infection without using these drugs.

In recent years, as a preventive method for preventing infection, a method of administering a large amount of various vitamins such as vitamin C, vitamin E, pantothenic acid and choline chloride has been proposed [Journal of the Fisheries Society of Japan, 54 ( 1), 141-144 (1988)
Etc.], some effects are recognized but they are not sufficient, and they do not actively prevent infection.

In addition, prevention of fish diseases based on immunopotentiating activity
FK-565 as a therapeutic agent (Japanese Patent Laid-Open No. 63-233923), a specific crude drug or its extract (Japanese Patent Laid-Open No. 64-75426, etc.),
Further, it has been reported that a polysaccharide having a β-1,3-glucan structure derived from fungi or yeast is effective for infectious diseases of fish (JP-A-2-218615).

On the other hand, with regard to seaweed polysaccharides, there are known examples showing effects on mammalian tumors (food and development, Vo.
L.25, No.3, 32-38, 1990) has not been reported to be effective for bacterial infection of fish.

[0006]

DISCLOSURE OF THE INVENTION The present invention solves the problems of conventional antibiotics and synthetic antibacterial agents, is not inferior to the efficacy of antibacterial agents and synthetic antibacterial agents, and uses fish as a safe food. It intends to provide a drug that can prevent fish infections.

[0007]

[Means for Solving the Problems] The inventors of the present invention have focused their attention on enhancing the antibacterial activity and immunity of fishes, and as a result of diligent research, selected from brown algae and red algae among seaweeds. The present inventors have found that the extracted seaweed extract has an effect of preventing infectious diseases of fish, and completed the present invention.

That is, the present invention includes fukuronori, habanori, sardine, wakame, arame, kajime, mizushikomubu, mackerel, jolomoku, hijiki, akiyoremok, fusijimoku, akamoku, yanagimoku, yoremok, umitranoo, vendeamanori, arisa, arisa.
For the prevention of infectious diseases of fish, which contains ingredients extracted from water selected from seaweed selected from Onia manori, Ganoderma lucidum, Hanafunori, Fukurofunori, Matsunori, Tsunomata, Ibaranori, Amicus, and Drosophila melanogaster, which can be used as safe food. It provides an effective drug.

(Seaweed) The seaweed used in the present invention is selected from brown algae and red algae. Specifically, among brown algae,
Fukuronori, Habanori, sardine, seaweed, alame, Kajime, citrus kelp, macaque, jolomoku, hijiki, akiremok, fusijimoku, akamoku, willow moss, yaremoku, mizunori, mizunori, swordfish, among the red algae They are Hanafunori, Fukurofunori, Matsunori, Tsunomata, Ibaranori, Amixa, and Drosophila nori.

[0010] Even with the same seaweeds, water extract components from green algae such as Usubaonori and Anahusa have almost no effect, and even brown algae and red algae, for example, iroro, shiwanokawa, chigaiso, shimeji, gagome, Brown algae such as Tamaha Hakimoku, Narasamo, Yasumatamoku, Pirihiba,
Water extract components from red algae such as centipede, ogonori, birch, eucalyptus, and mitsudesoso have little effect.

Among the above-mentioned seaweeds used in the present invention, sardine, seaweed (grown leaf), mackerel, Akiyoremok, Fusijimoku, Susabinori, Fukurofunori, Matsunori, Tsunomata, Ibara Nori, Dwarf Nori are relatively easy to obtain. It is also preferable in terms of the effect.

(Water Extraction) The drug of the present invention contains a component extracted from the above specific brown algae and red algae with water.

The water extraction is generally carried out by using 1 to 100 liters of water, preferably 5 to 10 liters of water per 100 parts by weight of dried seaweed, and immersing the seaweed in this water, and then extracting as it is or by heating to 70 ° C. or higher. To do.

The extraction temperature is not particularly limited, but in cold water extraction, it is generally 1 to 48 hours, preferably 12 to 48 hours with water at 0 to 20 ° C.
Soak for ~ 24 hours. At this time, it is preferable to assist the extraction by stirring or the like. It should be noted that hot water having a temperature of higher than 20 ° C is not preferable because the seaweed may spoil during long-term immersion. On the other hand, in the case of hot water extraction, generally 70
Dry seaweed powder is added to water at a temperature of not less than ℃, preferably 90 ℃ ~ boiling, and extracted for 1 to 12 hours, preferably 3 to 5 hours.

After completion of the water extraction, the residue is removed by centrifugation and the aqueous layer is freeze-dried to obtain the extract as a powdery or fibrous solid. The yield of solid matter varies depending on the type of seaweed used and the extraction conditions, but is usually 10 to 45%.

[0016] Although the components of the extract are not clear, in the case of hot water extraction containing a seaweed polysaccharide such as fucoidan, there is a possibility that some such as those having a sulfate group have been decomposed and modified.

(Method of use) Examples of fishes to which the drug of the present invention is applied and infectious diseases thereof include vibrio diseases such as yellowtail, red sea bream, puffer fish, flounder, grouper, coho salmon, rainbow trout, eel, carp, ayu, tilapia. ( Vibrio anguill
arum), edwardsiellosis disease (Edwardsiella tarda), kind nodule disease (Pasteurella piscicida), streptococcal disease (Streptoc
occus sp.), nocardiosis ( Nocardia campachi ),
Bacterial gliding disease ( Flexibacter sp.), Aeromonosis ( Aero
monas hydrophila , Aeromonas salmonicida ) and other bacterial infections.

The agent of the present invention is used by oral administration, intraperitoneal administration, intramuscular administration, or by immersing fish in an aqueous solution of the agent of the present invention.

For oral administration, the seaweed extract of the present invention is usually added to, for example, 0.001 to 10
%, Preferably 0.01 to 5%, and administered as a feed.

For intraperitoneal administration or intramuscular administration, the seaweed extract of the present invention is usually used as an aqueous solution prepared by dissolving it in sterile physiological saline. In this case, even if it is not completely dissolved but partially suspended, it can be used as it is.

In the case of intraperitoneal administration, for example, 0.1-10%,
It is preferably administered by intraperitoneal injection as a 0.5-1.0% aqueous solution, or by intramuscular injection as a 1-10%, preferably 5-10% aqueous solution by injection into the muscle. The dose is generally 1 to 200 mg / kg fish body weight of the seaweed extract, preferably 10 to 50 mg / kg fish body weight for both intraperitoneal and intramuscular administration.

When the fish is immersed in the aqueous solution of the drug, the seaweed extract is usually added in an amount of 0.001 to 1%, preferably 0.01 to 0.5.
% Of fresh water or seawater for 1 minute to 2 hours, preferably 10 minutes to 1 hour, and short time immersion for 3 to 7 days in the same fresh water or seawater. is there.

[0023]

The present invention will be described in detail with reference to the following examples.

Example 1 and Comparative Example 1 (Preparation of seaweed extract) From March 30 to April 19, 1991, the seaweeds shown in Table 1 were collected on the coast of Tsuyazaki-cho, Fukuoka Prefecture and air-dried overnight. Then, it was freeze-dried. 100 dry seaweeds each
5 g of water was added to g, and the mixture was allowed to stand still in water at 95 ° C for 3 hours and then centrifuged to obtain a seaweed extract. The obtained extract is freeze-dried using a freeze dryer to obtain a seaweed extract.
Obtained 12-45g.

(Protective effect against carp against carp) For each seaweed extract, carp (average weight: 25.6 ± 3.9 g) purchased from the Sugishima Fish Farm in Yatsushiro on May 22, 1991 and June 24, 1991 for each 5
Using a tail, an aqueous solution of seaweed extract prepared by dissolving 1 g of the above seaweed extract in 100 ml of 0.8% saline was used per 1 kg of fish weight.
50 mg (seaweed extract dry weight) at a rate of 2 every 2 days
It was administered once intraperitoneally. The same amount of physiological saline was intraperitoneally administered to the control fish.

[0026] Edwardsiella tarda 3 days after the last administration
NG8104 (3 × 10 ⁷ CFU / 100 g) was inoculated intraperitoneally. Table 1 shows the survival rate 7 days after the bacterial attack.

[0027]

[Table 1] Survival rate of seaweed (%) ──────────────── Example (Brown algae) Fukuronori 80 Habanori 60 Sardine bean 80 Wakame (adult leaf) 100 Alame 60 60 Kajime 80 Mitsuishikonbu 80 Macombus 80 Jolomok 80 Hijiki 60 Akiyoremok 100 Fushijimoku 80 Akamok 80 Yanagimoku 60 Yoremok 60 Umitranoo 60

(Rhodophyta) Bendea Nori 80 Asakusanori 60 Susabinori 80 Onia Manori 60 Pomegranate 100 Hanafunori 100 Fukurofunori 100 Matsunori 80 Tsunomata 100 Ibaranori 100 Amixa 60 Shojo Kenori 60

Comparative Example (Brown algae) Iroro 20 Shiwanokawa 20 Chigai 0 Stripe 0 Kagome 20 Tamaha Hakimoku 20 Narasamo 0 Yasumatamoku 20

(Red algae) Pirihiba 0 Mukadenori 20 Ogonori 0 Cabanoris 20 Yukari 0 Mitsudesoso 20

(Green algae) Usubaaonori 20 Anahaosa 20

The survival rate of the control fish intraperitoneally administered with physiological saline was 20%.

Example 2 For each of the seaweed extracts shown in Table 2, 10 yellowtails (average weight 77.1 ± 18.6 g) of Mitsubishi Petrochemical Co., Ltd. fish farm on July 30, 1991
Using the tail, in the same manner as in Example 1, 50 mg per 1 kg of fish weight
(Seaweed extract dry weight)
It was administered intraperitoneally twice every two days. The control fish received only the same amount of physiological saline.

On the third day after the final administration, Streptococcus sp.
(1 × 10 ⁶ CFU / 100 g) was intraperitoneally inoculated. From fungus attack
Table 2 shows the survival rate on the 7th day.

[0035]

[Table 2] Survival rate of seaweed (%) ───────────────── (Brown algae) Iwahigashi 100 Seaweed (adult leaves) 90 Mitsuishikonbu 100 Macombus 60 Aquiloremoku 90 Fushijimoku 100

(Red algae) Susabinori 100 Fukurofunori 100 Matsunori 70 Tsunomata 40 Ibaranori 80 Shojo Kenori 80

The survival rate of the control fish which was intraperitoneally administered with physiological saline was 20%.

Example 3 For each of the seaweed extracts shown in Table 3, 10 yellowtail juveniles (average weight of 45 ± 5 g) at Mitsubishi Petrochemical Co., Ltd. fish farm on July 10, 1991
Using a tail, 100 mg (seaweed extract dry weight) per 1 kg of fish weight was used and orally administered for 10 days using Mitsubishi Yuka Co., Ltd. yellowtail pellet feed containing 1% by weight of seaweed extract.

On the third day after the final administration, Streptococcus sp.
(1 × 10 ⁵ CFU / 100 g) was inoculated intraperitoneally. From fungus attack
Table 3 shows the survival rate on the 7th day.

[0040]

[Table 3] Survival rate of seaweed (%) ──────────────── (Brown algae) Wakame 80 Wakame (adult leaves) 100 Alame 80 Macomb 70 Macomb (bottom of leaf) 90 Akiyoremoku 100

(Red algae) Susabinori 100 Fukurofunori 100

The survival rate was 40% in the case of the control fish using the yellowtail pellet feed containing no seaweed extract.

Example 4 About each seaweed extract shown in Table 4, juvenile yellowtail fry (average weight 45 ± 5 g) of Mitsubishi Yuka Co., Ltd. fish farm on July 10, 1991, 10 each
With tail, after receiving the test fish 3 days fish water tank of 120 l of the respective seaweed extract satisfies the seawater containing 0.1%, St
Reptococcus sp. (1 × 10 ⁵ CFU / 100 g) was inoculated intraperitoneally and returned to the aqueous layer again. Table 4 shows the survival rate 7 days after the bacterial attack.

[0044]

[Table 4] Survival rate of seaweed (%) ──────────────── (Brown algae) Wakame 70 Wakame (adult leaves) 80 Alame 40 Macomb 40 Macomb (bottom of leaf) 60 Akiyoremoku 80

(Red algae) Susabinori 70 Fukurofunori 90

The survival rate of the control fish treated in the same manner with seawater containing no seaweed extract was 30%.

[0046]

INDUSTRIAL APPLICABILITY By using the drug of the present invention, the disease resistance and immunity of fish are enhanced, bacterial infection of fish can be prevented, and fish can be used as a safer food. it can. In addition, it can be expected to improve the therapeutic effect in combination with a drug for treating fish.

Claims (3)

[Claims] Claims 1. Fukuronori, Habanori, sardine, seaweed, alame, Mitsuishikonbu, Kajime, Macombus, Jolomok, Hijiki, Akiyoremok, Fusijimoku, Akamoku, Yanagomiku, Yoremok, Umitranoo, Bendeamanori, Anoha, Asakusa Nori, Asakusa Nori, Asakusa Nori, Asakusa Nori, Asakusa Nori, Asakusa Nori, Asakusa Nori, Asakusa Nori, Asakusa Nori, Asakusa Nori, Asakusa Nori A preventive agent for infectious diseases of fish, comprising a component extracted from water selected from seaweed selected from fukurofunori, matsunori, tsunomata, iwaranori, mikusa, and drosophila mori. 2. The drug according to claim 1, wherein the water extraction is performed at a temperature of 0 to 20 ° C. 3. The drug according to claim 1, wherein the water extraction is performed at a temperature of 70 ° C. or higher.