Medicinal preparation for preventing tail-rot disease of cynoglossus semilaevis

Abstract

The invention relates to the technical field of pharmaceutical preparations, in particular to a pharmaceutical preparation for preventing tail rot of cynoglossus semilaevis, the pharmaceutical preparation is a drug-containing pellet with a three-layer coating structure, the drug-containing pellet comprises a drug-containing pellet core, active ingredients of the drug-containing pellet core comprise a first antibiotic and a second antibiotic, the first antibiotic is a DNA synthesis inhibitor, and the second antibiotic is a DNA synthesis inhibitor. The second antibiotic is a protein synthesis inhibitor; the drug-containing pellet core is coated with the pH-sensitive enteric-coated layer; the enteric-coated layer is coated with the bioadhesive sustained-release layer. According to the embodiment of the invention, the outer sustained-release layer reduces the dissolution loss rate of the medicine in water to 10% or below; the middle enteric-coated layer ensures that the medicine can directly reach the intestinal tract by 100%; and the inner adhesive layer enables the drug effect to last for 6-8 hours. DNA and a protein synthesis inhibitor are combined, through a dual-action mechanism and a synchronous release technology, the drug resistance risk is greatly reduced, the curative effect is remarkably improved, relapse is reduced, and the problems that a traditional scheme is poor in drug effect, prone to drug resistance, single in prevention and control and the like are fundamentally solved.

Description

Technical Field

[0001] This invention relates to the field of pharmaceutical preparation technology, specifically to a pharmaceutical preparation for preventing tail rot in the tongue sole. Background Technology

[0002] As an important marine aquaculture fish in my country, the half-smooth tongue sole has experienced frequent outbreaks of diseases caused by Vibrio alginolyticus in recent years due to the expansion of aquaculture scale, resulting in huge economic losses to the aquaculture industry. Vibrio alginolyticus belongs to the Vibrio genus of the Vibrioceae family. It is a Gram-negative short bacillus and a typical marine opportunistic pathogen. It is prone to outbreaks and epidemics at water temperatures above 20°C, with rapid spread and high mortality. After infection with Vibrio alginolyticus, the main manifestations in half-smooth tongue sole are: loss of scales and ulceration on the ocular side of the body surface, formation of ulcers, and tail rot, with some individuals also having ascites; congestion and redness of the muscles on the unocular side of the body or fins, even with blood spots; anemia in the gills, rotting of the gill filaments, and some resembling petals; shedding and reddening of the intestinal mucosa and submucosa, with white feces in the intestines; linear congestion in the liver, pale color and partial enlargement of the gallbladder, and mostly pale coloration of the mesonephroides, which seriously affect the survival and growth of the half-smooth tongue sole.

[0003] Current prevention and control technologies mostly employ single antibiotics or conventional disinfection methods. The use of single antibiotics easily leads to drug resistance in Vibrio alginolyticus; for example, some strains are already insensitive to seven antibiotics, including ampicillin, amoxicillin, and doxycycline. Conventional disinfection schemes (such as using chlorine dioxide or povidone-iodine alone) can only perform basic disinfection of the water body and cannot effectively target Vibrio alginolyticus infecting the fish. Furthermore, there is a lack of a systematic approach that coordinates internal and external prevention and control, making it difficult to simultaneously address both aquatic environmental sterilization and the elimination of pathogens within the fish's body. This results in limited prevention and control effectiveness and fails to meet the needs of the half-smooth tongue sole farming industry for efficient and safe control of Vibrio alginolyticus disease. Summary of the Invention

[0004] This application provides a pharmaceutical preparation for preventing tail rot in half-smooth tongue sole, thereby addressing the problems in the prior art such as poor efficacy in preventing and controlling Vibrio alginolyticus disease in half-smooth tongue sole, easy development of drug resistance, and lack of synergistic control strategies.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows: The present invention provides a pharmaceutical preparation for preventing tail rot in the tongue sole, wherein the pharmaceutical preparation is a drug-containing microsphere with a three-layer coating structure, and the drug-containing microsphere comprises:

[0006] The product contains a pill core, wherein the active ingredients comprise a first antibiotic and a second antibiotic, wherein the first antibiotic is a DNA synthesis inhibitor and the second antibiotic is a protein synthesis inhibitor;

[0007] A pH-sensitive enteric coating layer surrounding the drug-containing pellet core; and

[0008] A bioadhesive sustained-release layer encapsulating the enteric coating.

[0009] Based on the above technical means, the outer layer of this application embodiment is a bioadhesive sustained-release layer, which has both waterproof properties and intestinal targeted retention capability. On the one hand, it effectively resists the erosion and loss of drugs by the water environment, controlling the drug loss during the feeding process to less than 10%. On the other hand, it prolongs the residence time of drugs in the intestine through bioadhesion, extending the effective duration of action from 2-4 hours of conventional formulations to 6-8 hours, significantly improving drug utilization efficiency. The middle layer is a pH-sensitive enteric coating layer, which utilizes the pH difference between the stomach and the intestine to form a protective barrier in the stomach, achieving zero irritation and zero loss, avoiding the destruction of drug components by gastric acid, and precisely triggering drug release in the intestine, ensuring that 100% of the drug enters the target site of action, ensuring precise drug efficacy. The inner layer is a drug-containing pellet core, which adopts solid dispersion technology to tightly mix the two core drugs, DNA synthesis inhibitor and protein synthesis inhibitor, at the molecular level, laying the structural foundation for the synchronous release and synergistic effect of the two drugs from the source of formulation.

[0010] Relying on the precise regulation of the three-layer structure, the blood drug concentrations of the two core drugs are precisely matched with "synchronous peak and synchronous decay" after absorption in the intestine. This kinetic optimization allows the potent synergistic effect of the two drugs (such as FIC index <0.5) verified in vitro to be fully released in vivo, completely avoiding the problem of synergistic failure caused by differences in drug absorption rate and metabolic rhythm, and maximizing the prevention and treatment potential of combined drugs. It specifically targets and kills pathogens in vivo, and is seamlessly connected with the "external environment blocking module" formed by chlorine dioxide water disinfection, to build a three-dimensional prevention and control system of "internal and external joint prevention and treatment of both symptoms and root causes" that "blocks the spread of pathogens in vitro and eliminates infectious bacteria in vivo". It exerts dual efforts from the source of disease transmission and the core link of infection to achieve comprehensive prevention and control.

[0011] Preferably, the material of the bioadhesive sustained-release layer is selected from chitosan, sodium alginate, or carbomer.

[0012] Preferably, the material of the pH-sensitive enteric coating is selected from hydroxypropyl methylcellulose phthalate, hydroxypropyl methylcellulose acetate succinate, or acrylic resin.

[0013] According to the above technical means, the embodiments of this application maintain structural integrity and do not dissolve in the strongly acidic environment of the fish's stomach (pH usually <3.0), forming a reliable physical barrier; once the microspheres enter the neutral to weakly alkaline environment of the intestine (pH>6.5) with the food, the material layer dissolves and disintegrates rapidly, precisely triggering the release of the internal drug.

[0014] Preferably, the DNA synthesis inhibitor is a fluoroquinolone antibiotic, and the protein synthesis inhibitor is an aminoglycoside antibiotic.

[0015] Preferably, the fluoroquinolone antibiotic is enrofloxacin, the aminoglycoside antibiotic is neomycin sulfate, and the weight ratio of enrofloxacin to neomycin sulfate is (3.5:1) to (4.5:1).

[0016] Based on the aforementioned technical means, in this embodiment, enrofloxacin, as a DNA synthesis inhibitor, targets bacterial DNA gyrase, directly blocking the flow of genetic information by interfering with bacterial DNA replication, repair, and transcription, leading to rapid bacterial death. Neomycin sulfate, as a protein synthesis inhibitor, irreversibly binds to the 30S subunit of the bacterial ribosome, causing codon misreading and resulting in the synthesis of a large number of non-functional erroneous proteins, thus damaging its functional execution units. Therefore, even if bacteria exhibit temporary adaptive adjustments to one drug, these adjustments will be rapidly disrupted by the action of the other drug, fundamentally reducing the probability of drug-resistant mutations being screened out, and providing a molecular basis for a strong synergistic effect.

[0017] Preferably, the DNA synthesis inhibitor is an amide alcohol antibiotic, and the protein synthesis inhibitor is a tetracycline antibiotic.

[0018] Preferably, the amide alcohol antibiotic is florfenicol, the tetracycline antibiotic is doxycycline, and the weight ratio of florfenicol to doxycycline is (2.0:1) to (2.5:1).

[0019] Based on the aforementioned technical means, in this application embodiment, florfenicol, as an amide alcohol drug, inhibits peptidyl transferase activity by binding to the 50S subunit of bacterial ribosomes, thus blocking peptide chain elongation; doxycycline, as a tetracycline drug, binds to the 30S subunit of ribosomes to prevent aminoacyl-tRNA from entering the A site, thus blocking peptide chain initiation. The two drugs form a "pincer attack" targeting the key steps of bacterial protein synthesis initiation and elongation, resulting in a significant synergistic bactericidal effect. This combination has a completely different mechanism of action than the enrofloxacin and neomycin combination, providing an important alternative for clinical use while possessing targeted resistance-breaking capabilities. Florfenicol is not affected by common tetracycline efflux pumps and can kill strains resistant to doxycycline, while doxycycline can cover strains with low florfenicol sensitivity, forming bidirectional protection.

[0020] Preferably, the particle size of the drug-containing microspheres is 100-500 micrometers, and the thickness of the bioadhesive sustained-release layer is 20-100 micrometers.

[0021] This application also discloses a method for preparing a pharmaceutical preparation for preventing tail rot in the tongue sole, comprising the following steps:

[0022] S1: Provide a pill core containing the active ingredient;

[0023] S2: Using a fluidized bed coating process, the pH-sensitive enteric coating layer and the bioadhesive sustained-release layer are sequentially coated onto the surface of the drug-containing pellet core to form the drug-sensitive enteric coating layer and the bioadhesive sustained-release layer.

[0024] This application also proposes the use of a pharmaceutical preparation for preventing tail rot in half-smooth tongue sole in the preparation of a drug for the prevention and / or treatment of Vibrio alginolyticus infection in half-smooth tongue sole.

[0025] The beneficial effects achieved by using the present invention described above are as follows:

[0026] 1. This invention prepares a drug formulation for preventing tail rot in half-smooth tongue sole. This formulation achieves a breakthrough upgrade in physical delivery through a three-layer composite structure design. The outermost bioadhesive sustained-release layer has excellent hydrophobic and adhesive properties, resisting water erosion and reducing the water solubility loss rate of drug microparticles during feeding from 50% to less than 10% compared to traditional feed mixing, achieving near-zero waste of drug resources and directly reducing medication costs and environmental residues. The middle pH-sensitive enteric layer acts like a smart switch, utilizing the pH difference between the stomach and intestines to ensure that the microparticles pass through the acidic environment of the stomach 100% intact. This avoids the chemical damage of the drug (especially enrofloxacin) to the stomach acid and prevents irritation and damage to the gastric mucosa, delivering the drug efficacy 100% accurately to the intestines. The bioadhesive layer absorbs water and gels in the intestines, adhering tightly to the intestinal wall, allowing the drug to be released slowly through a gel diffusion mechanism. The effective action time is extended from 2-4 hours for ordinary formulations to 6-8 hours, maintaining a stable and sustained effective concentration in vivo, and significantly reducing the feeding frequency.

[0027] 2. This application employs a golden combination of DNA synthesis inhibitors and protein synthesis inhibitors. Enrofloxacin acts on bacterial DNA gyrase, interfering with DNA replication, repair, and transcription, thus blocking the flow of genetic information. Neomycin sulfate binds to the 30S subunit of the bacterial ribosome, causing codon misreading and damaging the functional execution unit. Florfenicol binds to the 50S subunit of the ribosome, blocking peptide chain elongation, and doxycycline binds to the 30S subunit of the ribosome, blocking peptide chain initiation. These two combinations construct a dual killing network from different dimensions, ensuring a stable in vitro synergistic index (FIC) ≤0.5. Simultaneously, solid-state dispersion pellet technology allows for molecular-level mixing of the two drugs, coupled with precise controlled-release coating, ensuring simultaneous release, absorption, and peak concentration of the drugs in the intestine. This solves the problem of synergistic failure caused by pharmacokinetic differences in traditional compound formulations, fully translating the laboratory-verified in vitro synergistic effect into in vivo, increasing the cure rate from 40-65% for single-drug formulations to over 96%.

[0028] 3. Simultaneously, the two core drugs have vastly different mechanisms of action. Bacteria need to undergo multiple independent gene mutations simultaneously to develop resistance to both, a probability that is extremely low. After application, the incidence of pathogen resistance can be reduced by more than 60%, building a robust defense for key antibiotics and significantly extending the drug's clinical lifespan. Furthermore, the two preferred combination therapies—enrofloxacin and neomycin sulfate, and florfenicol and doxycycline—have completely different pathways of action. The former attacks the flow of genetic information and functional execution units, while the latter targets the initiation and extension of protein synthesis. This provides reliable first-line treatment and second-line alternatives for clinical use, supporting farmers in implementing scientific drug rotation, preventing the directed evolution of stable drug-resistant populations by pathogens at the ecosystem level, and systematically delaying the overall development of drug resistance.

[0029] 4. This formulation is not a single treatment tool, but a core component of a three-dimensional prevention and control system. As a highly efficient "in-body precision clearance module," it can seamlessly connect with the "external environment blocking module" formed by conventional water disinfection (such as chlorine dioxide) to construct an integrated prevention and control system that combines internal and external prevention and treatment of both symptoms and root causes. The external module blocks the transmission path of pathogens through water disinfection, reducing the risk of infection in fish; the internal module precisely clears pathogens from already infected fish, forming a closed-loop prevention and control system through dual efforts. Practical verification has shown that this three-dimensional prevention and control system can not only increase the overall cure rate of half-smooth tongue sole tail rot by 5-8%, but also reduce the disease recurrence rate by more than 60%, realizing a systematic upgrade from single treatment to a full-chain prevention and control system of "treatment-blocking-prevention," providing a more comprehensive and long-lasting solution for disease prevention and control in aquaculture.

[0030] This solves the problems of poor efficacy, easy development of drug resistance, and lack of synergistic control programs in existing technologies for preventing and controlling Vibrio alginolyticus disease in tongue sole.

[0031] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Detailed Implementation

[0032] The technical solution of the present invention is illustrated below through specific examples. It should be understood that the one or more method steps mentioned in the present invention do not preclude the existence of other method steps before or after the combined steps, or the insertion of other method steps between these explicitly mentioned steps; it should also be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the present invention. Furthermore, unless otherwise stated, the numbering of each method step is merely a convenient tool for identifying each method step, and not for limiting the order of the method steps or defining the scope of the present invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the present invention.

[0033] To better understand the above technical solutions, exemplary embodiments of the present invention are described in more detail below. While exemplary embodiments of the present invention are shown, it should be understood that the present invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present invention and to fully convey the scope of the invention to those skilled in the art.

[0034] The following describes a pharmaceutical formulation for preventing tail rot in half-smooth tongue sole, based on embodiments of this application. Addressing the poor treatment efficacy mentioned in the background section, this application provides a pharmaceutical formulation for preventing tail rot in half-smooth tongue sole. This method utilizes a three-layer composite delivery structure and synergistic drug combination to achieve a systematic upgrade in aquatic disease prevention and control. The outer sustained-release layer reduces drug loss in water to below 10%; the middle enteric layer ensures 100% direct delivery of the drug to the intestines; and the inner adhesion layer maintains efficacy for 6-8 hours. By employing a combination of DNA and protein synthesis inhibitors, and through a dual-action mechanism and simultaneous release technology, the cure rate is increased to over 96%, while significantly reducing the risk of drug resistance. Furthermore, this formulation can be combined with water disinfection to construct a three-dimensional "internal and external prevention" system, significantly improving efficacy and reducing recurrence, fundamentally solving the problems of poor efficacy, easy drug resistance, and limited control methods associated with traditional approaches.

[0035] The present invention will be further described in conjunction with the following embodiments.

[0036] Example 1

[0037] A pharmaceutical preparation for preventing tail rot in the tongue sole, comprising drug-containing microcapsules with a three-layer coating structure, the microcapsules including:

[0038] It contains a pill core, in which the active ingredients include a first antibiotic and a second antibiotic, wherein the first antibiotic is a DNA synthesis inhibitor and the second antibiotic is a protein synthesis inhibitor;

[0039] A pH-sensitive enteric coating encapsulating the core of the pill; and

[0040] A bioadhesive sustained-release layer encapsulated outside the enteric coating.

[0041] The bioadhesive sustained-release layer is made of chitosan.

[0042] The pH-sensitive enteric coating is made from hydroxypropyl methylcellulose phthalate.

[0043] Among them, DNA synthesis inhibitors are fluoroquinolone antibiotics, and protein synthesis inhibitors are aminoglycoside antibiotics.

[0044] Among them, the fluoroquinolone antibiotic is enrofloxacin, the aminoglycoside antibiotic is neomycin sulfate, and the weight ratio of enrofloxacin to neomycin sulfate is 3.5:1.

[0045] The particle size of the drug-containing microspheres is 100-500 micrometers, and the thickness of the bioadhesive sustained-release layer is 20-100 micrometers.

[0046] This application also discloses a method for preparing a pharmaceutical preparation for preventing tail rot in the tongue sole, comprising the following steps:

[0047] S1: Provides a pill core containing active ingredients;

[0048] S2: A fluidized bed coating process is used to sequentially coat the surface of the drug-containing pellet core to form a pH-sensitive enteric coating layer and a bioadhesive sustained-release layer.

[0049] It should be noted that the pharmaceutical preparation prepared in this application can be used in combination with a water disinfectant to construct a three-dimensional prevention and control system that works synergistically inside and outside the body. The water disinfectant is chlorine dioxide, and its concentration is set at 0.5-3 mg / L, more preferably 2 mg / L, to achieve a concentration of 0.5-3 mg / L in the pool water.

[0050] This application also proposes the use of a pharmaceutical preparation for preventing tail rot in half-smooth tongue sole in the preparation of a drug for the prevention and / or treatment of Vibrio alginolyticus infection in half-smooth tongue sole.

[0051] Specifically, in a large-scale half-smooth tongue sole farm in Hebei Province, during the high-temperature period of summer 2023, an outbreak of Vibrio alginolyticus tail rot occurred. The traditional method of administering medication by mixing it with feed had a cure rate of only about 40% and the disease recurred frequently.

[0052] Using the pharmaceutical formulation prepared according to the embodiments of this application, enrofloxacin and neomycin sulfate were mixed into a three-layer coated microsphere (core-enteric layer-bioadhesion layer) at a ratio of 3.5:1 and fed twice daily; simultaneously, the entire pond was disinfected with chlorine dioxide at a concentration of 2 mg / L. After 5 days of treatment, the clinical symptoms of the diseased fish significantly improved, and the ulcer lesions began to heal; at the end of the treatment course, the clinical cure rate of the diseased group in the aquaculture pond reached 96%, an improvement of more than 50 percentage points compared with the traditional method.

[0053] Twenty days of follow-up observation after drug withdrawal showed that the disease recurrence rate was controlled below 5%, while the recurrence rate of traditional treatments usually exceeded 30%. Furthermore, the three-layer coating structure reduced the drug loss in water from approximately 50% with traditional feed to below 10%, resulting in a reduction of approximately 30% in the actual total antibiotic usage, significantly lowering treatment costs. Environmental monitoring data indicated that antibiotic residues in the aquaculture water were reduced by more than 60% compared to traditional administration methods, while chlorine dioxide disinfection kept the pathogen load in the water consistently low.

[0054] Example 2

[0055] A pharmaceutical preparation for preventing tail rot in the tongue sole, comprising drug-containing microcapsules with a three-layer coating structure, the microcapsules including:

[0056] It contains a pill core, in which the active ingredients include a first antibiotic and a second antibiotic, wherein the first antibiotic is a DNA synthesis inhibitor and the second antibiotic is a protein synthesis inhibitor;

[0057] A pH-sensitive enteric coating encapsulating the core of the pill; and

[0058] A bioadhesive sustained-release layer encapsulated outside the enteric coating.

[0059] The material of the bioadhesive slow-release layer is sodium alginate.

[0060] The pH-sensitive enteric coating is made from hydroxypropyl methylcellulose acetate succinate.

[0061] Among them, DNA synthesis inhibitors are fluoroquinolone antibiotics, and protein synthesis inhibitors are aminoglycoside antibiotics.

[0062] Among them, the fluoroquinolone antibiotic is enrofloxacin, the aminoglycoside antibiotic is neomycin sulfate, and the weight ratio of enrofloxacin to neomycin sulfate is 4:1.

[0063] The particle size of the drug-containing microspheres is 100-500 micrometers, and the thickness of the bioadhesive sustained-release layer is 20-100 micrometers.

[0064] This application also discloses a method for preparing a pharmaceutical preparation for preventing tail rot in the tongue sole, comprising the following steps:

[0065] S1: Provides a pill core containing active ingredients;

[0066] S2: A fluidized bed coating process is used to sequentially coat the surface of the drug-containing pellet core to form a pH-sensitive enteric coating layer and a bioadhesive sustained-release layer.

[0067] It should be noted that the pharmaceutical preparation prepared in this application can be used in combination with a water disinfectant to construct a three-dimensional prevention and control system that works synergistically inside and outside the body. The water disinfectant is chlorine dioxide, and its concentration is set at 0.5-3 mg / L, more preferably 2 mg / L, to achieve a concentration of 0.5-3 mg / L in the pool water.

[0068] This application also proposes the use of a pharmaceutical preparation for preventing tail rot in half-smooth tongue sole in the preparation of a drug for the prevention and / or treatment of Vibrio alginolyticus infection in half-smooth tongue sole.

[0069] Specifically, in the treatment of a 15% incidence of Vibrio alginolyticus tail rot disease outbreak at a half-smooth tongue sole farm in Shandong (stocking density 2000 fish / 500m² pond), the three-dimensional prevention and control scheme of this invention was adopted: enrofloxacin and neomycin sulfate (4:1) were made into three-layer coated microcapsules (capsule core - hydroxypropyl methylcellulose succinate enteric coating layer - sodium alginate adhesion layer), and the medicated feed was prepared at 45g / kg of feed and fed for 6 days; at the same time, 2mg / L chlorine dioxide was used for water disinfection for 3 consecutive days.

[0070] The following data can be obtained: Cure rate: The clinical cure rate reached 78% on the 6th day of treatment, 92% on the 10th day, and finally stabilized at 95% (the traditional method is 40-65%).

[0071] Prevention and control efficiency: The disease recurrence rate is controlled below 8% (traditionally 30-45%).

[0072] Economic benefits: Drug loss rate during administration is <10% (compared to about 50% with traditional methods), overall medication costs are reduced by 35%, and the treatment cycle is shortened by 25-40%;

[0073] Safety: After discontinuation of medication, the drug residue in the fish was within the standard (enrofloxacin <0.1mg / kg), and there were no harmful residues in the water.

[0074] In summary, the embodiments of this application provide a three-dimensional prevention and control scheme for the prevention and control of tail rot in half-smooth tongue sole. By combining oral administration of three-layer coated drug-containing microcapsules with external water disinfection, significant results have been achieved in real aquaculture scenarios.

[0075] Example 3

[0076] A pharmaceutical preparation for preventing tail rot in the tongue sole, comprising drug-containing microcapsules with a three-layer coating structure, the microcapsules including:

[0077] It contains a pill core, in which the active ingredients include a first antibiotic and a second antibiotic, wherein the first antibiotic is a DNA synthesis inhibitor and the second antibiotic is a protein synthesis inhibitor;

[0078] A pH-sensitive enteric coating encapsulating the core of the pill; and

[0079] A bioadhesive sustained-release layer encapsulated outside the enteric coating.

[0080] Carbomer is selected as the material for the bioadhesive sustained-release layer.

[0081] The pH-sensitive enteric coating is made of acrylic resin.

[0082] Among them, DNA synthesis inhibitors are fluoroquinolone antibiotics, and protein synthesis inhibitors are aminoglycoside antibiotics.

[0083] Among them, the fluoroquinolone antibiotic is enrofloxacin, the aminoglycoside antibiotic is neomycin sulfate, and the weight ratio of enrofloxacin to neomycin sulfate is 4.5:1.

[0084] The particle size of the drug-containing microspheres is 100-500 micrometers, and the thickness of the bioadhesive sustained-release layer is 20-100 micrometers.

[0085] This application also discloses a method for preparing a pharmaceutical preparation for preventing tail rot in the tongue sole, comprising the following steps:

[0086] S1: Provides a pill core containing active ingredients;

[0087] S2: A fluidized bed coating process is used to sequentially coat the surface of the drug-containing pellet core to form a pH-sensitive enteric coating layer and a bioadhesive sustained-release layer.

[0088] It should be noted that the pharmaceutical preparation prepared in this application can be used in combination with a water disinfectant to construct a three-dimensional prevention and control system that works synergistically inside and outside the body. The water disinfectant is chlorine dioxide, and its concentration is set at 0.5-3 mg / L, more preferably 2 mg / L, to achieve a concentration of 0.5-3 mg / L in the pool water.

[0089] This application also proposes the use of a pharmaceutical preparation for preventing tail rot in half-smooth tongue sole in the preparation of a drug for the prevention and / or treatment of Vibrio alginolyticus infection in half-smooth tongue sole.

[0090] Specifically, during an outbreak of tail rot at a large-scale tongue sole farming base in Ningde, Fujian (single pond area 300㎡, stocking density 12 fish / ㎡), the farm adopted the three-dimensional prevention and control plan of this invention for treatment. The specific implementation involved preparing medicated feed using a three-layer coated microsphere mixture of enrofloxacin and neomycin sulfate (4.5:1) at a ratio of 40kg / ton of feed, and feeding it twice daily for 5 consecutive days; simultaneously, water disinfection was carried out using 1.5mg / L chlorine dioxide for 3 consecutive days.

[0091] Results showed that on the 4th day of treatment, the fish's feeding rate recovered to 85%, and the congestion on their body surface significantly subsided; the clinical cure rate reached 78% on the 6th day; the final cure rate stabilized at 96.5%, and the recurrence rate within 30 days after drug withdrawal was only 4.2%. In terms of economic benefits, compared with traditional feed-mixed drug administration, this method reduced drug dosage by 38%, shortened the treatment cycle by 40%, and reduced overall drug costs by 35%. Safety testing showed that 7 days after drug withdrawal, the enrofloxacin residue in the fish muscle was 0.07 mg / kg, meeting the national residue limit standard, and did not cause continuous pollution to the aquaculture water.

[0092] Example 4

[0093] A pharmaceutical preparation for preventing tail rot in the tongue sole, wherein the pharmaceutical preparation is a drug-containing microsphere with a three-layer coating structure, the drug-containing microsphere comprising:

[0094] It contains a pill core, in which the active ingredients include a first antibiotic and a second antibiotic, wherein the first antibiotic is a DNA synthesis inhibitor and the second antibiotic is a protein synthesis inhibitor;

[0095] A pH-sensitive enteric coating encapsulating the core of the pill; and

[0096] A bioadhesive sustained-release layer encapsulated outside the enteric coating.

[0097] The material of the bioadhesive sustained-release layer is selected from carbomer.

[0098] The pH-sensitive enteric coating is made from hydroxypropyl methylcellulose phthalate.

[0099] Among them, DNA synthesis inhibitors are amide alcohol antibiotics, and protein synthesis inhibitors are tetracycline antibiotics.

[0100] Among them, the amide alcohol antibiotic is florfenicol, the tetracycline antibiotic is doxycycline, and the weight ratio of florfenicol to doxycycline is 2.0:1.

[0101] The particle size of the drug-containing microspheres is 100-500 micrometers, and the thickness of the bioadhesive sustained-release layer is 20-100 micrometers.

[0102] This application also discloses a method for preparing a pharmaceutical preparation for preventing tail rot in the tongue sole, comprising the following steps:

[0103] S1: Provides a pill core containing active ingredients;

[0104] S2: A fluidized bed coating process is used to sequentially coat the surface of the drug-containing pellet core to form a pH-sensitive enteric coating layer and a bioadhesive sustained-release layer.

[0105] It should be noted that the pharmaceutical preparation prepared in this application can be used in combination with a water disinfectant to construct a three-dimensional prevention and control system that works synergistically inside and outside the body. The water disinfectant is chlorine dioxide, and its concentration is set at 0.5-3 mg / L, more preferably 2 mg / L, to achieve a concentration of 0.5-3 mg / L in the pool water.

[0106] This application also proposes the use of a pharmaceutical preparation for preventing tail rot in half-smooth tongue sole in the preparation of a drug for the prevention and / or treatment of Vibrio alginolyticus infection in half-smooth tongue sole.

[0107] Specifically, during an outbreak of Vibrio alginolyticus infection at a half-smooth tongue sole farm in Qingdao, Shandong, the farm adopted the three-dimensional prevention and control plan of this invention for treatment. The specific implementation involved: preparing medicated feed using three-layer coated microspheres made from florfenicol and doxycycline (2.0:1) at a ratio of 35 kg / ton of feed, and feeding the fish twice daily for 6 consecutive days; simultaneously, disinfecting the water with 2 mg / L chlorine dioxide for 3 consecutive days.

[0108] Results showed that on day 4 of treatment, the clinical improvement rate of diseased fish reached 75%, and the congestion on the body surface significantly subsided; on day 6, the clinical cure rate reached 92%; the final cure rate stabilized at 96%, and the recurrence rate within 30 days after drug withdrawal was only 5.2%. In terms of economic benefits, compared with traditional feed-mixed drug administration, this method reduced drug dosage by approximately 35%, shortened the treatment cycle by 25-30%, and reduced overall drug costs by 32%. Safety testing showed that florfenicol residues in fish muscle were below 0.1 mg / kg 7 days after drug withdrawal, meeting national residue limits, and did not cause sustained pollution to the aquaculture water.

[0109] Example 5

[0110] A pharmaceutical preparation for preventing tail rot in the tongue sole, wherein the pharmaceutical preparation is a drug-containing microsphere with a three-layer coating structure, the drug-containing microsphere comprising:

[0111] It contains a pill core, in which the active ingredients include a first antibiotic and a second antibiotic, wherein the first antibiotic is a DNA synthesis inhibitor and the second antibiotic is a protein synthesis inhibitor;

[0112] A pH-sensitive enteric coating encapsulating the core of the pill; and

[0113] A bioadhesive sustained-release layer encapsulated outside the enteric coating.

[0114] The bioadhesive sustained-release layer is made of chitosan.

[0115] The pH-sensitive enteric coating is made from hydroxypropyl methylcellulose acetate succinate.

[0116] Among them, DNA synthesis inhibitors are amide alcohol antibiotics, and protein synthesis inhibitors are tetracycline antibiotics.

[0117] Among them, the amide alcohol antibiotic is florfenicol, the tetracycline antibiotic is doxycycline, and the weight ratio of florfenicol to doxycycline is 2.5:1.

[0118] The particle size of the drug-containing microspheres is 100-500 micrometers, and the thickness of the bioadhesive sustained-release layer is 20-100 micrometers.

[0119] This application also discloses a method for preparing a pharmaceutical preparation for preventing tail rot in the tongue sole, comprising the following steps:

[0120] S1: Provides a pill core containing active ingredients;

[0121] S2: A fluidized bed coating process is used to sequentially coat the surface of the drug-containing pellet core to form a pH-sensitive enteric coating layer and a bioadhesive sustained-release layer.

[0122] It should be noted that the pharmaceutical preparation prepared in this application can be used in combination with a water disinfectant to construct a three-dimensional prevention and control system that works synergistically inside and outside the body. The water disinfectant is chlorine dioxide, and its concentration is set at 0.5-3 mg / L, more preferably 2 mg / L, to achieve a concentration of 0.5-3 mg / L in the pool water.

[0123] This application also proposes the use of a pharmaceutical preparation for preventing tail rot in half-smooth tongue sole in the preparation of a drug for the prevention and / or treatment of Vibrio alginolyticus infection in half-smooth tongue sole.

[0124] Specifically, a recirculating aquaculture system for half-smooth tongue sole in Dalian, Liaoning Province, experienced an outbreak of Vibrio alginolyticus infection in August 2023. The water temperature in the aquaculture pond was 25-27℃, the pond area was 200㎡, and the stocking density was 15 fish / ㎡. The affected fish exhibited typical symptoms of fin rot, with congestion and ulceration of the tail fin and multiple ulcerative lesions on the body surface. The daily morbidity rate was 1.2%, and the cumulative infection rate reached 18%.

[0125] Using the proposed method, florfenicol and doxycycline (2.5:1) were formulated into three-layer coated microspheres (pill core - hydroxypropyl methylcellulose acetate succinate enteric coating layer - chitosan adhesion layer). This was administered as medicated feed at a rate of 38 g / kg of feed for 6 days, while simultaneously disinfecting the water with 2 mg / L chlorine dioxide for 3 days. This treatment resulted in an 85% clinical improvement rate on day 4, 95% on day 6, and a final cure rate of 97.2%. The recurrence rate within 30 days after discontinuation of medication was only 3.8%. Compared to traditional methods, the drug dosage was reduced by 36%, the treatment cycle was shortened by 33%, and the overall cost was reduced by approximately 30%. Safety testing showed that florfenicol residue in the fish was only 0.08 mg / kg 7 days after discontinuation of medication, meeting national standards and causing no sustained environmental pollution.

[0126] Comparative Example 1

[0127] Traditional feed-mixed drug administration regimens, under the same aquaculture area and conditions, use the traditional method of directly mixing antibiotics into feed to treat Vibrio alginolyticus tail rot. Enrofloxacin and neomycin sulfate (3.5:1) raw drug powders are directly mixed with feed and fed for 7 days, supplemented by routine water disinfection.

[0128] The results showed that the cure rate was only 42%, and the relapse rate within 30 days after drug withdrawal was as high as 38%. The drug loss rate during administration exceeded 50%, and the gastric degradation rate was approximately 30%, leading to a significant reduction in actual efficacy, a long treatment cycle, and high overall costs. Compared with traditional methods, the present invention (Example 1) demonstrates significant advantages in terms of cure rate (increased by 128%), relapse control (reduced by 87%), drug utilization efficiency (increased by 81%), and treatment cost (reduced by 35%).

[0129] Comparative Example 2

[0130] A comparative study was conducted using monolayer enteric-coated microspheres with the same drug composition (enrofloxacin + neomycin sulfate, 4:1). This comparative sample only contained the hydroxypropyl methylcellulose phthalate (HPMCP) enteric layer and lacked the outermost bioadhesive sustained-release layer.

[0131] The results showed that although the single-layer microspheres could ensure drug release in the intestine (gastric passage rate > 95%), due to the lack of an adhesive layer, the microspheres only remained in the intestine for 1–2 hours. More than 80% of the drug was rapidly released within 2 hours, resulting in excessively high local concentrations and a short overall duration of action. The final cure rate was 68%, and the recurrence rate reached 22%, significantly lower than the double-layer coated formulation of this invention (Example 2, cure rate 95%, recurrence rate < 8%).

[0132] Comparative Example 3

[0133] A control group was set up to receive enrofloxacin alone. The same breeding conditions and infection status as in Example 1 were used, and the drug was administered in feed at the standard treatment dose.

[0134] The results showed that the cure rate of enrofloxacin alone was 48%. During the treatment, the MIC value of enrofloxacin against Vibrio alginolyticus increased by 8 times. The detection rate of drug-resistant bacteria after treatment reached 35%, and the relapse rate after drug withdrawal was as high as 45%.

[0135] Compared with Example 1 of this invention (enrofloxacin + neomycin sulfate combination, cure rate 96%), single antibiotic regimens have significant shortcomings in terms of efficacy, drug resistance control, and recurrence rate. This application, through the combination of antibiotics with different mechanisms of action, not only significantly improves the bactericidal effect (synergistic index FIC≤0.5), but also greatly reduces the risk of bacteria developing drug resistance through multi-target attack.

[0136] Comparative Example 4

[0137] A control group was set up to receive neomycin sulfate alone. The same breeding conditions and infection status as in Example 1 were used, and the drug was administered as a single treatment at the standard treatment dose mixed with feed.

[0138] The results showed that the cure rate of neomycin sulfate alone was 52%. During treatment, the MIC value of neomycin sulfate increased sixfold; the detection rate of drug-resistant bacteria reached 28% after treatment, and the relapse rate after drug withdrawal was as high as 40%.

[0139] Compared with Example 1 of this invention (enrofloxacin + neomycin sulfate combination, cure rate 96%), single antibiotic regimens have significant shortcomings in terms of efficacy, drug resistance control, and recurrence rate. This application, through the combination of antibiotics with different mechanisms of action, not only significantly improves the bactericidal effect (synergistic index FIC≤0.5), but also greatly reduces the risk of bacteria developing drug resistance through multi-target attack.

[0140] Comparative Example 5

[0141] Parallel application tests were conducted using microparticles with a commercially available combination (Eudragit L100 enteric coating layer + carbomer adhesive layer).

[0142] The results showed that although the combination could achieve basic enteric coating (gastric pass rate of 95%), the drug adhesion time in the intestine was only 4–6 hours, and the simultaneous release rate of the two antibiotics was only 85%. In actual treatment, the final cure rate was 78%, which was significantly lower than the preferred combination of this application (Example 2: HPMCP + sodium alginate, cure rate 95%; Example 5: hydroxypropyl methylcellulose acetate succinate + chitosan, cure rate 97.2%).

[0143] In summary, the choice of coating material directly affects drug delivery efficiency and synergistic effects. The material combinations selected through screening in this application (such as HPMCP / sodium alginate, hydroxypropyl methylcellulose acetate succinate / chitosan, etc.) are significantly superior to conventional combinations in terms of intestinal permeability, adhesion time, simultaneous drug release, and final efficacy, demonstrating the crucial role of material selection in achieving precise delivery and efficient treatment.

[0144] This application provides a pharmaceutical formulation for preventing tail rot in half-smooth tongue sole. Through a three-layer composite delivery structure and synergistic drug combination, it achieves a systematic upgrade in aquatic disease prevention and control. Its outer sustained-release layer reduces drug loss in water to below 10%; the middle enteric layer ensures 100% drug delivery to the intestines; and the inner adhesion layer maintains efficacy for 6-8 hours. Utilizing a combination of DNA and protein synthesis inhibitors, through a dual-action mechanism and simultaneous release technology, it increases the cure rate to over 96% and significantly reduces the risk of drug resistance. Furthermore, this formulation can be combined with water disinfection to construct a three-dimensional "internal and external prevention" system, significantly improving efficacy and reducing recurrence, fundamentally solving the problems of poor efficacy, easy drug resistance, and limited control methods associated with traditional treatments.

[0145] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A pharmaceutical preparation for preventing tail rot in the tongue sole, characterized in that, The pharmaceutical preparation is a drug-containing microsphere with a three-layer coating structure, the drug-containing microsphere comprising: The product contains a pill core, wherein the active ingredients comprise a first antibiotic and a second antibiotic, wherein the first antibiotic is a DNA synthesis inhibitor and the second antibiotic is a protein synthesis inhibitor; A pH-sensitive enteric coating layer surrounding the drug-containing pellet core; and A bioadhesive sustained-release layer encapsulating the enteric coating.

2. The pharmaceutical preparation for preventing tail rot in half-smooth tongue sole according to claim 1, characterized in that, The material of the bioadhesive sustained-release layer is selected from chitosan, sodium alginate, or carbomer.

3. A pharmaceutical preparation for preventing tail rot in half-smooth tongue sole according to claim 1 or 2, characterized in that, The pH-sensitive enteric coating material is selected from hydroxypropyl methylcellulose phthalate, hydroxypropyl methylcellulose acetate succinate, or acrylic resin.

4. The pharmaceutical preparation for preventing tail rot in half-smooth tongue sole according to claim 1, characterized in that, The DNA synthesis inhibitor is a fluoroquinolone antibiotic, and the protein synthesis inhibitor is an aminoglycoside antibiotic.

5. A pharmaceutical preparation for preventing tail rot in half-smooth tongue sole according to claim 4, characterized in that, The fluoroquinolone antibiotic is enrofloxacin, the aminoglycoside antibiotic is neomycin sulfate, and the weight ratio of enrofloxacin to neomycin sulfate is (3.5:1)-(4.5:1).

6. A pharmaceutical preparation for preventing tail rot in half-smooth tongue sole according to claim 1, characterized in that, The DNA synthesis inhibitor is an amide alcohol antibiotic, and the protein synthesis inhibitor is a tetracycline antibiotic.

7. A pharmaceutical preparation for preventing tail rot in half-smooth tongue sole according to claim 6, characterized in that, The amide alcohol antibiotic is florfenicol, the tetracycline antibiotic is doxycycline, and the weight ratio of florfenicol to doxycycline is (2.0:1) to (2.5:1).

8. A pharmaceutical preparation for preventing tail rot in half-smooth tongue sole according to claim 1, characterized in that, The particle size of the drug-containing microspheres is 100-500 micrometers, and the thickness of the bioadhesive sustained-release layer is 20-100 micrometers.

9. A method for preparing a pharmaceutical formulation for preventing tail rot in the tongue sole as described in any one of claims 1-8, characterized in that, Includes the following steps: S1: Provide a pill core containing the active ingredient; S2: Using a fluidized bed coating process, the pH-sensitive enteric coating layer and the bioadhesive sustained-release layer are sequentially coated onto the surface of the drug-containing pellet core to form the drug-sensitive enteric coating layer and the bioadhesive sustained-release layer.

10. The use of a pharmaceutical preparation for preventing tail rot in half-smooth tongue sole according to any one of claims 1-8 in the preparation of a medicament for the prevention and / or treatment of Vibrio alginolyticus infection in half-smooth tongue sole.