JP5584890B2 - A method for controlling schistosomiasis of fish and a method for controlling schistosomiasis of fish - Google Patents

Description

  The present invention comprises 2-cyclohexylcarbonyl-1,2,3,6,7,11b-hexahydro-4H-pyrazino [2,1-a] isoquinolin-4-one (generic name: Praziquantel) as an active ingredient The present invention relates to a method for controlling schistosomiasis of fish, characterized by administering to the fish schistosomiasis control for fish and Prajiquantel.

  Praziquantel is known to be effective in the treatment of human liver fluke, pulmonary fluke, and Yokokawa fluke (Non-Patent Document 1). Praziquantel is approved by veterinary drugs (fishery use) as a pesticide parasite, Benedenia seriolae (single post sucker) (patent document 1), but these parasites are It is parasitic on the epidermis of fish and not on blood vessels.

  The schistosomiasis of fish parasitizes in the arteries from the heart to the pupa (Buri spp.), In the blood vessels of the internal organs (Pufferfish), and in the arteries from the heart to the pupa (Tuna spp.). In the genus Buri and Tuna, the insects die by clogging in the blood vessels of the coral or heart, and in the pufferfish, the blood vessels of the internal organs, resulting in a high death rate and causing great damage. In addition, even if a drug against fish parasites is against parasites belonging to the same schistosomiasis, the effect differs depending on the genus / species of the target fish, and therefore development of an effective drug is not easy.

  As for the anthelmintic effect of Praziquantel on fish fluke, the effect has been studied in three kinds of fish, Sawara, Hiramasa, and Trafugu, but no clear effect has been confirmed. In the examination of the control effect of sawara against schistosomiasis by praziquantel, it has been reported that the number of deaths decreased by the dose of praziquantel formulation 300mg / Kg / day, but the number of eggs retained again increased (Non-patent document 2). . In the examination of the effect of Praziquantel on schistosomiasis larvae, it was not confirmed, and in the examination of the effect of trough pufferfish on metacercaria in the brain, it was reported that metacercaria was not killed by medication. (Non-patent Document 3). That is, in the past, a clear effect has not been obtained in the extermination of fish fluke by Praziquantel.

Japanese Patent No. 3290137

Pharmaceutical package insert Birtriside tablet (Brazicantel tablet) 600mg, 2009, page 1-3 2001 Kagawa Prefectural Fisheries Experiment Station Project Report, 2002, pages 97-98 2004 Nagasaki Prefectural Fisheries Experiment Station Report, 2005, pages 163-170

  In recent years, it has been known that schistosomiasis belonging to the genus Kardikola is infested with tuna, unlike other fish, but the schistosomiasis parasitizing the heart that affects mortality is not even specified. (However, Cardicola opisthorchis was identified at a later date), its removal method is completely unknown. In resource nationalism, restrictions are placed on imports of high-quality fish such as bluefin tuna, and it is desired to improve fish culture techniques. In particular, it is desirable to eliminate schistosomiasis parasitic on the blood vessels of fish during the culture. An object of the present invention is to provide a drug effective for controlling schistosomiasis of fish, particularly tuna.

The present invention comprises (1) 2-cyclohexylcarbonyl-1,2,3,6,7,11b-hexahydro-4H-pyrazino [2,1-a] isoquinolin-4-one (generic name: Pradiquantel) as an active ingredient A schistosomibicide for fish,
(2) The pesticide according to (1), wherein the fish is a fish belonging to the genus Tuna, and the schistosomiasis is a fluke belonging to the genus Cardicola
(3) The pesticide according to (2), wherein the fish belonging to the genus Tuna is bluefin tuna, southern bluefin tuna or yellowfin tuna,
(4) The pesticide according to (1), wherein the fish is a yellowtail or amberjack belonging to the genus Buri, and the schistosome is a fluke belonging to the genus Paradeon Tacilix, or (5) Further, the present invention relates to a pesticide according to (1), wherein the schistosomiasis is a fluke belonging to the genus Psetterium.
(6) In addition, the aquatic feed containing the pesticide according to any one of (1) to (5) is also included in the present invention.
The present invention also provides (7) a method for controlling schistosomiasis of fish, characterized in that the drug is administered to a fish.
(8) The extermination method according to (7), wherein the fish is a fish belonging to the genus Tuna, and the schistosomes are flukes belonging to the genus Cardicola,
(9) The pesticide method according to (8), wherein the fish belonging to the genus Tuna is bluefin tuna, southern bluefin tuna or yellowfin tuna,
(10) The pesticide method according to (7), wherein the fish is a yellowtail or amberjack belonging to the genus Buri, and the schistosomiasis is a fluke belonging to the genus Paradeon Tacilix, or (11) A tiger puffer or a riverfish belonging to the order Pufferfish Further, the present invention relates to the extermination method according to (7), wherein the schistosomiasis is a fluke belonging to the genus Pssetarium.

  According to the present invention, there is provided a schistosomiasis control agent for fish containing praziquantel as an active ingredient.

  2-Cyclohexylcarbonyl-1,2,3,6,7,11b-hexahydro-4H-pyrazino [2,1-a] isoquinolin-4-one used in the present invention is a known pharmaceutical compound whose general name is called praziquantel Japanese Patent Application Laid-Open No. 50-93999 describes a production method thereof.

  In the present invention, “fish” is not particularly limited, but the pesticide of the present invention is preferably used for fish used for aquaculture. Among such fish, fish belonging to the genus Thunnus, Fish belonging to the genus (Seriola) or fish belonging to the order of Tetraodontiformes is preferable, and fish belonging to the genus Tuna is particularly preferable. As the fish belonging to the genus Tuna, bluefin tuna (Thunnus orientalis, Thunnus thynnus), southern bluefin tuna (Thunnus maccoyii) or yellowfin tuna (Thunnus albacares) are preferred, and bluefin tuna is particularly preferred. As the fish belonging to the genus Buri, yellowtail (Seriola quinqueradiata), amberjack (Seriola dumerili) or tigerfish (Seriola lalandi) is preferable, and as the fish belonging to the pufferfish, Takifugu rubripes or Stephanolepsis cirrhifer is preferable.

  In the present invention, the term “schistosomiasis” includes any parasite that is generally referred to as schistosomiasis, and specific examples of schistosomiasis include Cardicola orientalis, C. sp. (identified as C. opisthorchis)), Paradeon tacilix genus (Paradeontacylix grandispinus, P. kampachi, etc.) that parasitize the yellowtail, and Psettarium spp. The pesticide is preferably used especially for schistosomes belonging to the genus Cardicola.

  These schistosomes parasitize in the arteries from the heart of the fish to the coral, in the blood vessels of the internal organs, in the arteries of the vaginal valve, and lay eggs. The pesticide of the present invention can be suitably used especially for schistosomiasis parasitic on the heart.

  In the present invention, the term “control agent” refers to a drug that can reduce the number of parasites in fish individuals or reduce damage to fish caused by parasites. The disinfectant of the present invention can be used as praziquantel alone, but praziquantel is formulated with other additives to prepare a marine product, or praziquantel is dissolved or suspended in a solvent such as ethanol as necessary, and then feed And the mixture can be dried to obtain aquatic feed, or the aquatic feed can be molded into solid feed (dry pellets, extruder pellets, etc.) and administered. Among these, it is preferable to administer the pesticide of the present invention as a fishery feed.

  The content of praziquantel in the aquatic preparation can be 10 to 90 parts by weight, preferably 20 to 80 parts by weight, and particularly preferably 30 to 70 parts by weight.

  Examples of additives used in the formulation include excipients, spreading agents, stabilizers, etc. Among these, excipients include, for example, lactose, starch, glucose, dextrin, cellulose, Examples thereof include gelatin and casein. Examples of the spreading agent include sodium alginate, gluten, monocalcium phosphate, polyethylene glycol, guar gum, sodium polyacrylate, natural gums, and the like. Specific product names of spreading agents include, for example, A trade name “Senku-kun” (manufactured by Asuka Pharmaceutical Co., Ltd.) containing sodium alginate, sodium polyacrylate, monocalcium phosphate and guagam. Furthermore, examples of the stabilizer include propylene glycol, magnesium chloride, calcium ascorbate, tocopherol acetate, ethoxyquin, and sodium pyronitrite. These can be used alone or in combination.

  The content of praziquantel in the aquatic feed of the present invention can be 0.01 to 20 parts by weight, preferably 0.05 to 2.0 parts by weight, and the feed content can be 80.0 to 99.99 parts by weight. Parts, preferably 98-99.95 parts by weight. In addition, 0.1 to 5.0 parts by weight of the stabilizer and / or 0.1 to 10.0 parts by weight of an excipient can be added to the aquatic feed as necessary.

  Examples of the feed contained in the aquatic feed of the present invention include raw foods such as sardine (minced), mackerel (minced), horse mackerel (minced), and squid (minced), fish meal, squid meal, krill meal, kaim meal, and feed Examples thereof include yeast, moist pellets, solid feed (dry pellets, extruder pellets, etc.), and these may be commercially available feeds or mixed feeds.

  When the aquatic feed of the present invention is a solid feed, in order to prevent a decrease in the palatability of the feed and make it difficult to leak praziquantel from the solid feed when fed, the solid feed is gelatin, methylcellulose, carboxymethylcellulose. Coating with ethyl cellulose, cellulose acetate phthalate, hydroxypropyl methylcellulose, fish oil, vegetable oil or the like is preferred. Examples of the coating method include known methods such as fluidized bed coating, Wurster coating, and jet stream dispersion coating.

  The pesticide of the present invention can also be used for immersion treatment. When using for the immersion treatment, a solvent and / or a solubilizing agent may be added. Examples of the solvent include ethyl alcohol. Examples of the solubilizer include polyvinyl pyrrolidone, sorbitan monostearate, sorbitan monopalmitate, sorbitan monolaurate, and polyvinyl alcohol. Furthermore, by using fish oil, vegetable oil, or the like as an additive, it is possible to more suitably perform dissolution of plaziquantel and adhere to an individual.

  In the “method for controlling schistosomiasis of fish” according to the present invention, the dose for oral administration of the aquatic preparation or the aquatic feed is 1 to 1 g, preferably 10 to 10 per gram of fish body weight per day. It can be in the range of 200 mg, more preferably 3 to 200 mg, particularly preferably 20 to 50 mg, more particularly preferably 7 to 50 mg. Dosing is once or twice a day. The number of administration days is 1 to 10 days, preferably 2 to 5 days, particularly preferably 3 to 4 days. Further, the dosing period is not limited to one time, but a plurality of dosing periods can be provided at intervals of 1 to 30 days, preferably 3 to 10 days.

  Examples and test examples of the present invention are shown below.

  Praziquantel formulation (trade name “Hadaclean” (registered trademark), manufactured by Bayer Yakuhin Co., Ltd.) 21 g containing 50% praziquantel is suspended in 500 ml of 99.5% ethanol, and this is mixed feed (trade name “Giant Tuna No. 8”, Japan The product was mixed with 2.0 kg (manufactured by Kiyomaru Beni feed Co., Ltd.), dried and coated with 22 ml of feed oil to prepare aquatic feed (Feed A).

  42 g of Hadaclean was suspended in 500 ml of 99.5% ethanol, mixed with 2.0 kg of Giant Tuna No. 8, dried, and then coated with 22 ml of feed oil to prepare aquatic feed (Feed B).

  30 g of Hadaclean, 40 g of carboxymethylcellulose, and 22 ml of feed oil were mixed with 8.0 kg of thawing squid, and aquatic feed (Food C) was prepared.

  54 g of Hadaclean, 40 g of carboxymethylcellulose, and 22 ml of feed oil were mixed with 8.0 kg of thawing squid, and aquatic feed (Feed D) was prepared.

  A bluefin tuna (Thunnus orientalis) juvenile with an average body weight of 0.7 kg, raised in sea bream with infestation of schistosomiasis (Cardicola spp.), Group A (232 tails at the start of the test, diet A and diet C administration group) and group B Divided into 215 fish at the start of the test, feed B and feed D medication group, 10 animals were collected from each group, and the parasitism rate of the eggs, the parasitic rate of the adults, the average number of eggs in the cage, in the heart The average number of adults was measured. After preliminary breeding for 4 days, the amount of feed for the active ingredient of the pesticide was set to approximately 150 mg / kg of fish body weight per day as the first dosing period, and the group A was prepared in Example 1 Feed A was administered to group B with feed B once a day for 3 days. After breeding without a disinfectant for a week, 10 animals were collected and measured for the parasitism rate of the eggs, the parasitic rate of the adults, the parasitic rate (adult), the average number of eggs in the cage, and the average number of adults in the heart did. After that, the second dose was started and the feed amount was set so that the dose of the active ingredient of the pesticide was approximately 150 mg per kg of fish body weight per day. Feed C was administered to group A and feed D was administered to group B for 3 days. did. 10 animals were collected after 5 days after the completion of medication, and the parasite rate of insect eggs, the parasitic rate of adults, the parasitic rate (adult), the average number of eggs in the cage, and the average number of adults in the heart were measured. There was no difference in effect between the group and group B, and the combined results are shown in Table 1.

  According to Table 1, the number of schistosomiasis in the heart was drastically reduced by the administration of Praziquantel and was not seen at all after the second administration.

※平均虫卵数/鰓弁及び平均成虫数/心臓は非寄生魚を除外して算出した。
※ＮＡ： 計数せず。
※(2：8)は投薬前のイ群とロ群の生け簀中の生魚2匹と死亡魚8匹を検査したこと、(0：10)は第1回投薬後のイ群とロ群の生け簀中の死亡魚10匹を検査したこと、(2：8)は第2回投薬後のイ群とロ群の生け簀中の生魚2匹と死亡魚8匹を検査したことを意味する。なお、死亡魚の死亡原因はCardicola spp.によるものではない。

* The average number of eggs / falcon and average number of adults / heart were calculated excluding non-parasitic fish.
* NA: Not counted.
* (2: 8) is the examination of 2 live fish and 8 dead fish in the slaughter group before the medication and the 2 group, and (0:10) is the 1 group after the first medication. Examination of 10 dead fish in the sacrifice, (2: 8) means examination of 2 live fish and 8 dead fish in the groups a and b after the second dose. The cause of death of dead fish is not due to Cardicola spp.

  Preliminary breeding was carried out for 1 week, using 354 juvenile bluefin tuna (Thunnus orientalis) fish with an average weight of 0.1 kg, which had been confirmed to be parasitic on schistosomiasis (Cardicola spp.). Feeding during pre-breeding was based on satiety feeding and was fed twice a day for the first 6 days and once a day on the final day until they no longer received mixed feed or minced squid. After pre-breeding, once a day (approximately 50 mg per kg of fish body weight) with the same satiety feed using a mixed feed (trade name “Giant Tuna 8”, manufactured by Nisshin Marubeni Feed Co., Ltd.) containing 54 g of Hadaclean (The average daily feed during the 24 days of the study was 7,445 kg (feeding per day: 4,215-10,002 kg, daily feeding during the dosing period of 3 days: 8,000 kg, 7,890 kg, 9,000kg)). 1 animal before dosing, 1 day of dosing, 2 days of dosing, 3 days of dosing, and 14 days after the end of dosing for 3 days each, the number of live parasites in the ventricle and pupae of the bluefin tuna, ventricle And the number of dead parasites in the pupae and the number of eggs in the pupae were measured. Three bluefin tuna on the first day of dosing were collected and measured immediately before feeding on the second day. Three bluefin tuna on the second day of dosing were collected and measured immediately before feeding on the third day. Three bluefin tuna on day 3 of dosing were sampled and measured on day 4.

The measuring method is to pick up the collected fish from the ginger and check for the presence or absence of adults in the living heart and arch (survival), and culvert (about 12 lobsters close to the heart of the right first arch) The presence or absence of the egg inside was confirmed. The results are shown in Table 2 below.
A large number of live schistosomiasis was confirmed in the heart and sputum before medication, and no dead schistosomiasis was confirmed. The worm body is considered to be Cardicola orientalis (Ogawa et al., 2010, Parasitology International, 59, pp. 44-48), and the heart worm body is considered to be another Cardicola (unidentified species (identified as Cardicola opisthorchis)).

  Looking at the post-medication situation, the schistosomiasis already alive on the first day of dosing was no longer seen in the ventricles or sputum. On day 3 of administration, almost no dead schistosomiasis was seen, and 14 days after the end of medication, no dead schistosomiasis was seen.

  However, schistosomiasis eggs have been confirmed in all individuals from pre-medication to 14 days after the end of dosing, and schistosomiasis eggs can be anthelminous by administration of Praziquantel (22.5 mg of Praziquantel per kg of fish body weight). I knew it couldn't be eliminated.

  In this study, the daily dose of Praziquantel was 22.5 mg / kg of fish body according to the instructions of the veterinarian, which was about 30% of the dose when Praziquantel was used to control yellowtail. It was. Nevertheless, schistosomiasis died from the first day of dosing. From this, it can be said that the anthelmintic effect of Praziquantel on Schistosoma japonicum was so remarkable that it was not necessary to perform statistical processing.

  The test subjects were 5,000 fish (Seriola quinqueradiata) with an average body weight of 1,500 g seaweed breeding confirmed to be parasitized with schistosomiasis (Paradeontacylix spp.).

  Praziquantel formulation (trade name “Benesal” (registered trademark), manufactured by Asuka Pharmaceutical Co., Ltd.) 750 g containing 50% by weight of praziquantel and a spreading agent (trade name “Tenkukun”) 220 kg (corresponding to 3% of the total fish weight) was fed once a day for 3 days using a mixed feed (trade name “Marine 11”, manufactured by Hayashi Kane Sangyo) containing 200 g of Asuka Pharmaceutical Co., Ltd.

  Ten animals were collected before and 5 days after the administration, and 5 animals were collected on the 20th day from the end of the administration, and the parasite rate of eggs, the parasitic rate of adults, and the average number of adults in the arteries from the heart to the pupae were measured. The results are shown in Table 3. In the yellowtail, a remarkable extermination effect (parasitism rate 0% 20 days after administration) was shown.

※平均成虫数は、非寄生魚を除外して算出した。

* The average number of adults was calculated excluding non-parasitic fish.

  Test subjects were 8,000 amberjacks (Serlola dumerili) with an average weight of 850 g, which were bred in sea surface where parasites of schistosomiasis (Paradeontacylix grandispinus, Paradeontacylix kampachi) were confirmed.

  Praziquantel formulation containing 50% by weight of praziquantel (trade name “Benesar” (registered trademark), manufactured by Asuka Pharmaceutical Co., Ltd.) 680 g (50 mg of plaziquantel per kg body weight of fish) and caking agent (carboxymethylcellulose, Wako Pure Chemical Industries, Ltd.) Using anchovy (frozen raw food) blended with 35 g (manufactured), 800 kg (corresponding to 3.5% of the total fish weight in terms of dry weight of the raw food) was fed once a day for 3 days.

  Ten animals were collected before and 5 days after the administration, and 5 animals were collected on the 20th day from the end of the administration, and the parasite rate of eggs, the parasitic rate of adults, and the average number of adults in the arteries from the heart to the moth were measured. The results are shown in Table 4. In amberjack, a significant extermination effect (0% parasitism 20 days after dosing) was shown.

※平均成虫数は、Paradeontacylix grandispinusとParadeontacylix kampachiの合計。
※平均成虫数は、非寄生魚を除外して算出した。

* The average number of adults is the sum of Paradeontacylix grandispinus and Paradeontacylix kampachi.
* The average number of adults was calculated excluding non-parasitic fish.

  Preliminary breeding was carried out for 1 week with 90 trough larvae with an average weight of 126 g infected with schistosomiasis (Psettarium spp.) As test subjects. The feed during the pre-breeding period is a moist produced at a ratio of 6.4: 1.6: 2 of frozen saba mince: frozen krill: mixed feed (trade name “Marine Light No. 8”, Hayashi Kaneko Co., Ltd.) The pellet was fed 350 g once a day.

  Divide the test fish into 3 aquariums of 30 fish each, and in each of the 2 aquariums, 1 sample of praziquantel formulation (trade name “Benesar” (registered trademark), manufactured by Asuka Pharmaceutical Co., Ltd.) containing 50% by weight of praziquantel On the day, 50 mg and 100 mg per kg fish weight were set. To administer 50 mg, 0.378 g of Benesal was blended with 100 g of the pre-bred feed, and 0.756 g of Benesal was blended with 100 g of the pre-bred feed to feed 100 mg, and fed once a day for 3 days. The remaining 1 tank was fed with 80 g of the same feed containing no Benesal as a control.

  5 days after the administration and 5 days after the completion of the administration, 5 fish were picked up from each water tank, and the parasitic ratio of eggs, the parasitic ratio of adults, and the average number of adults in the visceral blood vessels were measured. However, there was no difference in effect between 50 mg and 100 mg, and the combined results are shown in Table 5. Although only the result on the fifth day after the end of the medication, a significant extermination effect is observed also in the trough puffer if the results of the yellowtail and the amberjack on the fifth day after the end of the same medication are referred to.

※平均成虫数は、非寄生魚を除外して算出した。

* The average number of adults was calculated excluding non-parasitic fish.

The present invention is useful for prevention and control of schistosomiasis parasitic on fish.

Claims (9)

2-cyclohexylcarbonyl-1,2,3,6,7,11b-hexahydro-4H-pyrazino
An insecticide for schistosomiasis of fish comprising [2,1-a] isoquinolin-4-one as an active ingredient, wherein the fish is a fish belonging to the genus Tuna, and the schistosomiasis is an insecticide belonging to the genus Calcicola .   2. The pesticide according to claim 1, wherein the fish belonging to the genus Tuna is bluefin tuna, southern bluefin tuna or yellowfin tuna. 2-cyclohexylcarbonyl-1,2,3,6,7,11b-hexahydro-4H-pyrazino
A schistosome insecticide for fish comprising [2,1-a] isoquinolin-4-one as an active ingredient, wherein the fish is a yellowtail, amberjack or hiramasa belonging to the genus Brassica, and the schistosomiasis is a genus of Paradeon Tacilix An insecticide that is a fluke. 2-cyclohexylcarbonyl-1,2,3,6,7,11b-hexahydro-4H-pyrazino
It is a schistosomiasis agent for fishes that contains [2,1-a] isoquinolin-4-one as an active ingredient, and the fish is a tiger puffer or kingfisher that belongs to the order Pufferfish, and the schistosomiasis belongs to the genus Pssetarium Pesticide .   The feed for fisheries containing the disinfectant of any one of Claims 1-4.   7. A method for controlling disinfectant, comprising administering 7 to 50 mg of the disinfectant according to claim 1 to 1 kg of fish body weight. The extermination method according to claim 6 , wherein the fish belonging to the genus Tuna is bluefin tuna, southern bluefin tuna or yellowfin tuna. 7. A method for controlling an insecticide according to claim 3, wherein 7 to 50 mg is administered to 1 kg of fish body weight, wherein the fish belonging to the genus Brassica is a yellowtail or amberjack, and the schistosomes are paradeon tacilix. An extermination method that is a fluke belonging to the genus. 5. A method for controlling the insecticide according to claim 4, wherein 7 to 50 mg is administered to 1 kg of fish body weight, wherein the fish is a tiger puffer or a riverfish and the schistosomes belong to the genus Pssetarium. An extermination method that is fluke.