Natural medicine capable of killing cryptocaryon irritans and application of natural medicine in trachinotus ovatus feed
By adding curcumin to the golden pomfen feed, the limited and safe effects and safety problems of the prevention and control of seawater fish in the prior art are solved, and efficient and safe prevention and control effects are achieved.
Patent Information
- Application Number
- CN202411690854.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-25
- Publication Date
- 2025-02-28
AI Technical Summary
The prior art has limited physical and chemical control methods when preventing and controlling seawater fish to stimulate cryptocoratosis, and are not suitable for large open aquaculture water bodies, which poses food safety and environmental pollution risks.
Curcumin is used as a natural medicine, and the stimulating cryptocorticoids are killed by adding curcumin or its products to the golden pomfruit feed or directly into the water.
Curcumin has a good in vitro killing effect on stimulating cryptocorticoid larvae. The addition of curcumin to feed can improve the growth performance and intestinal health of cinocorticoid tract, effectively reduce the prevalence and infection mortality rate of stimulating cryptocorticoid tract, and has no drug residues and food safety risks.
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Abstract
Description
Technical Field
[0001] The invention relates to the technical field of aquaculture, in particular to a natural medicine capable of killing Cryptocaryon irritans and application of the natural medicine in golden pomfret feed. Background Art
[0002] Cryptocaryon irritans, commonly known as marine fish ichthyosis, is a parasitic disease of fish caused by Cryptocaryon irritans. The parasites mainly parasitize the skin and gills, and are characterized by the appearance of a large number of small white spots on the gills, around the eyes and skin of diseased fish (Li et al. 2022). The life cycle of Cryptocaryon irritans is divided into four stages: trophozoite, protomont, tomont and theront. The trophozoite grows and develops in the skin and gill cortex of the fish. After the trophozoite matures, it detaches from the fish body and enters the water body, attaches to the anchor to form a cyst and enters a dormant period. When the environment is suitable, the protoplasmic cells in the cyst undergo a series of divisions to form larvae. After the larvae mature, they overflow the cyst and enter the water body, becoming infectious larvae. Once the larvae encounter the host, they drill into the skin and gills to become trophozoites (Yu Lingying & Huang Xiaohong 2021, Jiao Kaiqiang et al. 2019). Cryptocaryon irritans can infect almost all marine bony fishes. It has the characteristics of rapid onset, fast spread, wide prevalence and high mortality rate. The mortality rates of oval pomfret, large yellow croaker, yellowfin sea bream and grouper after infection are 100%, 80%, 75% and 50%, respectively (Jiang Biao 2019, Huang Wei et al. 2015). Many marine economic fish species such as cobia, turbot, red sea bream and spotted seabass are also facing the threat and trouble of Cryptocaryon irritans, causing huge economic losses to my country's marine fish farming industry.
[0003] Traditional prevention and control of Cryptocaryon irritans mainly relies on physical methods and chemical drugs. Physical prevention mainly includes freshwater immersion, heat treatment, drying, rotational breeding, ultraviolet and ozone treatment of aquaculture water, etc. (Jiang et al. 2016, Cheng Qi & Pan Liande 2014, Hirazawa et al. 2003, Colorni 1993). Chemical prevention is mainly based on drug immersion. Commonly used drugs include copper sulfate (Wu Jianshao et al. 2019), formalin (Jiang Biao et al. 2018, Yan Maocang et al. 2008), nitazoxanide (Fan Haiping et al. 2016), sulfonamides (Kawano & Hirazawa 2012), malachite green (Farley 1980), sodium hypochlorite and benzalkonium chloride (Noritaka et al. 2003), etc. Although physical and chemical control can play a certain inhibitory and mitigating role, the effect is limited (Ma Ning et al. 2015, Cheng Qi et al. 2014), and it is not suitable for large, open aquaculture water bodies (Wang Xueqin & Yang Tao 2020). At the same time, chemical control may also bring food safety and environmental pollution risks. Therefore, it is urgent to research and develop green and safe control drugs for marine fish Cryptocaryon irritans.
[0004] Natural compounds have a short duration of action and no memory components, which is in line with the national concept of developing green and healthy aquaculture. It is the first choice for developing efficient and pollution-free drugs for the prevention and treatment of fish parasitic diseases. Curcumin belongs to the class of natural polyphenol compounds and has multiple effects such as antiparasitic, antibacterial, and antiviral (Urosevic et al. 2022, Alagawany et al. 2021, Elamin et al. 2021). A large number of studies have shown that curcumin can kill a variety of parasites that parasitize higher animals and humans (Faixova et al. 2021, Albalawi et al. 2021, Silva et al. 2019, Cheraghipour et al. 2018, Wachter et al. 2014, Nagajyothi et al. 2012, Haddad et al. 2011). However, there are few studies on the use of curcumin to prevent and control fish parasitic diseases. The only reports show that curcumin can kill the turbot parasite Philasterides dicentrarchi (Mallo et al. 2017) and the grass carp parasite Ichthyophthirius multifliis (Liu et al. 2017a, 2017b), but there are no reports on whether curcumin can kill Cryptocaryon irritans. Summary of the invention
[0005] The purpose of the present invention is to provide a natural medicine capable of killing Cryptocaryon irritans and its application in golden pomfret feed, so as to solve the problems existing in the above-mentioned prior art.
[0006] To achieve the above object, the present invention provides the following solutions:
[0007] One of the technical solutions of the present invention is the use of curcumin in preparing a product for killing Cryptocaryon irritans.
[0008] The second technical solution of the present invention is a product for killing Cryptocaryon irritans, wherein the product comprises curcumin.
[0009] The third technical solution of the present invention is a fish feed for preventing and treating Cryptocaryon irritans disease, which comprises 0.05 to 1 part of curcumin by weight, preferably 0.2 part.
[0010] The fourth technical solution of the present invention is a method for killing Cryptocaryon irritans in a water environment, which comprises adding curcumin or the product to the water to kill Cryptocaryon irritans.
[0011] Based on the above technical solution, the present invention has the following technical effects:
[0012] 1. The curcumin used in the present invention is a natural plant drug ingredient, which is characterized by a short action time and no memory component, so it will not cause drug residues and food safety problems.
[0013] 2. According to the in vitro killing test of curcumin on Cryptocaryon irritans larvae, it can be known that the use of curcumin at a concentration of 100 μM to treat Cryptocaryon irritans for 30 minutes can make it 100% dead, and the use of curcumin at a concentration of 60 μM to treat Cryptocaryon irritans for 4 hours can make it 100% dead; even the lower concentration of curcumin (20 μM) has a killing rate of up to 70% in a short period of time (30 minutes). These results show that curcumin has a good in vitro killing effect on Cryptocaryon irritans larvae, and therefore curcumin can be used as a highly effective drug for the prevention and treatment of Cryptocaryon irritans disease in marine fish.
[0014] 3. According to the growth, body composition, intestinal health, and lethality of Cryptocaryon irritans infection of golden pomfret fed with different concentrations of curcumin, adding 0.2% curcumin to feed is beneficial to the growth performance and intestinal morphology of golden pomfret, and can also effectively reduce the prevalence of Cryptocaryon irritans disease. Adding 0.1% or 0.2% curcumin to feed can increase the relative abundance of probiotics (such as Ralstonia) in the intestine of golden pomfret, inhibit the relative abundance of conditional pathogens (such as Escherichia_shigella), and there is no significant difference in the body composition of golden pomfret fed with different feeds. Therefore, adding 0.2% curcumin to feed is beneficial to the growth and intestinal health of golden pomfret, and can effectively reduce the lethality of Cryptocaryon irritans infection of golden pomfret, and will not change the body composition of golden pomfret. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0016] Figure 1 A diseased golden pomfret (A) and the trophozoites of Cryptocaryon irritans parasitizing its gill filaments (B: stereo microscope, magnification 180 times, C: ordinary optical microscope, magnification 100 times).
[0017] Figure 2 This is a Cryptocaryon irritans cyst under an ordinary optical microscope (magnification 100 times).
[0018] Figure 3 This is the larvae of Cryptocaryon irritans under an ordinary optical microscope (magnification 100 times).
[0019] Figure 4 The larvae of Cryptocaryon fasciatus were treated with gradient concentrations of curcumin (A) and their morphology under a microscope (B).
[0020] Figure 5 The survival of Cryptocaryon larvae after being treated with gradient concentrations of curcumin for 30 minutes (a) and 4 hours (b).
[0021] Figure 6 These are intestinal tissue sections of golden pomfret fed with different diets at the end of the experiment.
[0022] Figure 7 The intestinal microbial composition of golden pomfret fed with different diets at the end of the experiment. Among them, a: phylum level, b: genus level, c: species level. DETAILED DESCRIPTION
[0023] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but should be understood as a more detailed description of certain aspects, features, and embodiments of the present invention.
[0024] It should be understood that the terms described in the present invention are only for describing special embodiments and are not intended to limit the present invention. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper and lower limits of the scope is also specifically disclosed. Each smaller range between the intermediate value in any stated value or stated range and any other stated value or intermediate value in the described range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.
[0025] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.
[0026] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention description without departing from the scope or spirit of the present invention. Other embodiments derived from the present invention description will be apparent to those skilled in the art. The present application description and examples are exemplary only.
[0027] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.
[0028] The technical solutions described in the present invention, unless otherwise specified, are all conventional solutions in the art, and the reagents or raw materials used, unless otherwise specified, are purchased from commercial channels or have been disclosed.
[0029] The embodiment of the present invention provides the use of curcumin in preparing a product for killing Cryptocaryon irritans.
[0030] The embodiment of the present invention also provides a product for killing Cryptocaryon irritans, wherein the product comprises curcumin.
[0031] In some specific embodiments, the products include medicines, feeds and pesticides.
[0032] The embodiment of the present invention further provides a fish feed for preventing and treating Cryptocaryon irritans disease, wherein the feed comprises 0.2 parts of curcumin by weight.
[0033] In some specific embodiments, the feed further includes, by weight, 20-30 parts of fish meal, 15-20 parts of chicken meal, 1.5-2 parts of rapeseed meal, 3-5 parts of blood meal, 5-6 parts of gluten, 5-7 parts of soybean meal, 12-13 parts of flour, 2 parts of starch, 2 parts of calcium hydrogen phosphate, 0.2 parts of choline, 2 parts of mineral mixture and 6.5-7.5 parts of fish oil.
[0034] In some specific embodiments, the fish include all marine fishes that can be infected with Cryptocaryon irritans including golden pomfret.
[0035] The embodiment of the present invention also provides a method for killing Cryptocaryon irritans in a water environment, wherein curcumin or the product is added to the water to kill Cryptocaryon irritans.
[0036] In some specific embodiments, the curcumin is added at a concentration of 20 to 200 μM; and the killing treatment time is 30 to 240 min.
[0037] Example 1
[0038] 1 The curcumin used in this embodiment can be extracted from plants such as turmeric, turmeric and zedoary turmeric. In order to omit the extraction step, the curcumin used in this embodiment (purity of 98%) is a commercial reagent purchased from Beijing Inokai Technology Co., Ltd. Curcumin is insoluble in water. This experiment uses the chemical reagent dimethyl sulfoxide (DMSO) as a curcumin solvent to prepare a curcumin mother solution (concentration of 1mM).
[0039] 2. Stimulate the acquisition of Cryptocaryon worm body:
[0040] a. Pathogen confirmation: The gills of diseased golden pomfret (which sank to the bottom of the water, swam slowly, had no appetite, and were intolerant to low oxygen) were cut off and placed on a glass slide. Observation under a stereomicroscope revealed that the gill filaments were covered with oval worm bodies, which were consistent with the trophozoites of Cryptocaryon irritans described in the literature. Therefore, it was confirmed that the golden pomfret was infected with Cryptocaryon irritans.
[0041] b. Acquisition of Cryptocaryon irritans cysts: Place 15-20 golden pomfret infected with Cryptocaryon irritans into a 300L culture barrel, keep it oxygenated, and replace 50% of the seawater every other day. Place 2-3 2L beakers at the bottom of the culture barrel. After 3-4 days, remove the fish and drain the water in the culture barrel. Use a soft brush to sweep up and collect the cysts attached to the bottom of the culture barrel and those that have fallen into the beaker. After the cysts are allowed to settle, transfer them to a 250mL beaker, remove debris, and wash with seawater three times. Observe the collected cysts under an ordinary optical microscope to confirm whether the cysts have been collected. Cryptocaryon irritans cysts under a microscope are as follows: Figure 2 shown.
[0042] c. Cultivation of Cryptocaryon irritans larvae: Incubate the collected cysts at 24°C for 2-3 days to allow the cysts to hatch and the larvae to larvae to larvae. Count the hatched larvae using a hemocytometer. Take 20 μL of the worm liquid and add it to a hemocytometer. Fix the worms with 4% formaldehyde and count the larvae under a microscope. Repeat 10 times and calculate that about 650 Cryptocaryon irritans larvae are hatched per milliliter of seawater. Figure 3 shown.
[0043] 3 Study on the in vitro killing effect of curcumin on Cryptocaryon irritans:
[0044] The experiment set up 8 treatment groups, including 6 test groups (the final concentrations of curcumin were 20μM, 40μM, 60μM, 80μM, 100μM and 200μM, respectively), 1 positive control group (DMSO group for short, the DMSO concentration was the same as that in the 200μM group) and 1 blank control group (only 200μL sterilized seawater was added), and 3 parallels were set in each group. The larval insect liquid of Cryptocaryon irritans in the above steps was added to the 96-well plate, 50μL was added to each well, 4μL, 8μL, 12μL, 16μL, 20μL and 40μL of curcumin mother solution were added to each well of the test group, and the total volume of each well was adjusted to 200μL using sterilized seawater, so that the final concentrations of curcumin in the test group were 20μM, 40μM, 60μM, 80μM, 100μM and 200μM, respectively. The cells were incubated at 24°C, and the number of surviving larvae in each treatment group was recorded after 30 min and 4 h of incubation, respectively. Larvae with abnormal morphology and loss of motility were considered dead.
[0045] like Figure 5 As shown, the larvae of Cryptocaryon larvae were stimulated by curcumin treatment for 30 minutes, and the survival rates of the larvae in each treatment group were 100% (blank control group), 8.9% (DMSO group), 29.2% (20μM group), 30.3% (40μM group), 8.2% (60μM group), 7.0% (80μM group), and 0 (100μM and 200μM groups); the action time of curcumin was extended to 4h, and the survival rates of the larvae in each treatment group were 100% (blank control group), 7.0% (20μM group), 19.6% (40μM group), and 0 (DMSO group, 60μM, 80μM, 100μM and 200μM groups).
[0046] Taking the treatment time of 30 minutes as an example, the experimental results are analyzed as follows: the survival rate of the blank control group is 100%, indicating that the larvae hatched from the cysts have good vitality; according to the above experimental design, the dimethyl sulfoxide concentration in the DMSO group is consistent with that in the 200μM group, which is the highest (20%), while the dimethyl sulfoxide concentration in the 100μM, 80μM, 60μM, 40μM and 20μM groups gradually decreases, which are 10%, 8%, 6%, 4% and 2% respectively. The survival rates of the DMSO group and the 200μM group are 8.9% and 0, respectively, indicating that dimethyl sulfoxide itself is toxic to the larvae of Cryptocaryon irritans, but can only kill 91.1% of the larvae of Cryptocaryon irritans within 30 minutes, and can only be 100% with the assistance of curcumin. Killing of Cryptocaryon irritans larvae; the survival rate of the 100 μM group was 0, indicating that even when the concentration of dimethyl sulfoxide was reduced by half (10%), 100 μM curcumin could still kill 100% of Cryptocaryon irritans within 30 minutes; even in the 80 μM group (8%) and 60 μM group (6%) with lower dimethyl sulfoxide concentrations, with the assistance of lower concentrations of curcumin, the killing rate of Cryptocaryon irritans (60 μM group killing rate 91.8%, 80 μM group killing rate 93%) was close to that of the DMSO group (91.1%); in the 40 μM group (4%) and 20 μM group (2%) with the lowest dimethyl sulfoxide concentrations, with the assistance of the lowest concentrations of curcumin, the killing rates of Cryptocaryon irritans reached 70.8% and 69.7%, respectively.
[0047] The above results show that 100μM and 200μM curcumin treatment can kill 100% of Cryptocaryon irritans for 30 minutes, and 60μM and 80μM curcumin treatment can kill 100% of Cryptocaryon irritans for 4 hours; even the lower concentration of curcumin (20μM and 40μM) has a killing rate of up to 70% in a short period of time (30 minutes), indicating that curcumin has a good in vitro killing effect on Cryptocaryon irritans larvae.
[0048] 4 Research on the application of curcumin in golden pomfret feed
[0049] a. Curcumin-based golden pomfret feed configuration: A total of 7 kinds of artificial compound feeds were configured. Fish meal (30%), chicken meal (18%), rapeseed meal (1.8%), blood meal (4.2%), gluten (5.9%), soybean meal (6.1%), flour (12.5%), starch (2%), calcium hydrogen phosphate (2%), choline (0.2%), mineral mixture (2%), bentonite (8.8%) and fish oil (6.5%) were added in proportion to prepare the control group feed (abbreviated as R), and curcumin was added at concentrations of 0.05%, 0.1%, 0.2%, 0.4%, 0.8% and 1.0% on the basis of feed R to form feeds S1, S2, S3, S4, S5 and S6 respectively, and the content of bentonite in feeds S1-S6 was gradually reduced (8.7-7.8%) so that the total of each feed raw material was 100%.
[0050] b. Breeding conditions:
[0051] Fish species: Oval pomfret (commonly known as golden pomfret), weight 13.5 grams; breeding environment: 300-liter cylindrical tanks, with 18 fish in each tank; the main parameters of the breeding water (sand-filtered seawater) are: temperature 22.5-33.7℃, salinity 20-28‰, dissolved oxygen 7 mg / L.
[0052] c. Breeding process and methods:
[0053] Cultivation time: 8 weeks. Three tanks were fed with each feed. During the experiment, the feed was fed into the tank twice a day in sufficient quantity. The feeding method and environment were kept the same between tanks except for the feed. The total weight of the fish was weighed at the beginning and end of the experiment. After the experiment, the fish were sampled and analyzed for crude components, intestinal tissue morphology and intestinal microbial composition. After the sample collection, the fish fed with the same feed were gathered together, and 5-7 fish were randomly selected for gill inspection. No infection with Cryptocaryon irritans was found. Then, 15 fish of similar size were selected from the fish fed with the same feed and transferred to 3 new breeding tanks. 5 fish were placed in each tank. Except for the different nutritional backgrounds of the fish, other conditions and environments were kept the same between tanks. 2 ml of Cryptocaryon irritans larvae liquid was added to each tank. After that, feeding continued for one week. At the same time, the fish in each tank were observed and the number of deaths was counted.
[0054] d. Breeding results:
[0055] As can be seen from Table 1, compared with the golden pomfret fed with feed R, the golden pomfret fed with feeds S1-S6 had relatively higher fish weight and body weight gain at the end of the experiment, among which the fish fed with feed S3 had the highest weight gain.
[0056] Table 1 Growth and food utilization of golden pomfret fed with different diets
[0057] parameter R S1 S2 S3 S4 S5 S6 Final body weight (g) 52.55±4.94 55.51±2.89 58.72±3.18 61.12±1.18 57.92±2.60 55.19±4.21 55.29±4.71 Body weight gain (g) 39.12±5.08 42.09±2.72 45.26±2.97 47.73±1.09 44.33±2.47 41.53±4.23 41.65±4.76 <![CDATA[Food intake (%d -1 )]]> <![CDATA[4.41±0.23 ab ]]> <![CDATA[4.66±0.13 b ]]> <![CDATA[4.18±0.06 ab ]]> <![CDATA[4.75±0.59 b ]]> <![CDATA[4.41±0.39 ab ]]> <![CDATA[4.20±0.27 ab ]]> <![CDATA[3.70±0.07 a ]]> Feed Coefficient 2.11±0.20 2.15±0.07 1.91±0.07 2.06±0.22 1.93±0.14 1.96±0.20 1.76±0.15 Protein deposition efficiency (%) 17.81±1.76 16.20±1.17 16.46±1.70 17.68±2.40 17.28±0.42 19.42±5.01 18.95±1.10
[0058] As can be seen from Table 2, at the end of the experiment, there was no significant difference in the body composition of golden pomfret fed with different feeds.
[0059] Table 2 Body composition of golden pomfret fed with different diets at the end of the experiment
[0060] R S1 S2 S3 S4 S5 S6 Moisture (%) 65.60±1.59 66.52±1.66 66.92±1.42 65.70±1.58 65.82±1.72 65.67±0.36 66.34±1.97 Crude protein (%) 15.04±0.38 15.20±1.25 14.70±0.56 15.22±0.96 14.42±0.46 14.29±0.36 14.63±0.51 Crude fat (%) 15.14±1.42 13.65±1.24 13.62±1.36 14.80±0.66 14.75±1.72 14.30±0.88 14.76±2.11 Ash content (%) 3.81±0.19 4.06±0.22 4.00±0.18 4.44±0.33 3.91±0.26 4.07±0.25 3.89±0.03 phosphorus(%) 0.81±0.07 0.81±0.02 0.82±0.07 0.91±0.12 0.84±0.05 0.90±0.10 0.81±0.02
[0061] From Table 3 and Figure 6 It can be seen that compared with the golden pomfret fed with feed R, the height of the intestinal villi of the golden pomfret fed with feeds S3 and S6 increased significantly, and the number of goblet cells in the intestinal villi of the golden pomfret fed with feeds S3 and S6 increased significantly; secondly, the ratio of intestinal villus height to crypt depth of the golden pomfret fed with feeds S2, S3, S4 and S6 was higher than that of the golden pomfret fed with feed R; on the third day after the stimulation of Cryptocaryon fasciatus infection, the golden pomfret fed with feed R began to show loss of appetite and slowed swimming, and deaths began to occur from the fifth day, and the cumulative infection mortality rate within one week was 46.7%. However, the swimming activity and feeding activity of the golden pomfret fed with feeds S1-S6 did not change significantly and no deaths were found.
[0062] Table 3 Intestinal tissue morphology and Cryptocaryon irritans infection mortality of golden pomfret fed with different diets at the end of the experiment
[0063] R S1 S2 S3 S4 S5 S6 Villus height (μm) <![CDATA[657.0±119.1 bc ]]> <![CDATA[640.6±30.2 bc ]]> <![CDATA[680.4±126.3 bc ]]> <![CDATA[711.3±20.2 c ]]> <![CDATA[539.5±128.2 a ]]> <![CDATA[598.9±134.4 ab ]]> <![CDATA[702.8±49.5 c ]]> Crypt depth (μm) <![CDATA[32.22±2.49 cd ]]> <![CDATA[32.80±0.49 cd ]]> 26.94±5.08b <![CDATA[31.59±6.63 cd ]]> <![CDATA[23.39±6.24 a ]]> <![CDATA[34.00±3.67 d ]]> <![CDATA[30.45±6.14 c ]]> Number of goblet cells (per villus) <![CDATA[16.80±5.02 bc ]]> <![CDATA[15.63±7.70 bc ]]> 14.13±6.43ab <![CDATA[19.10±1.67 c ]]> <![CDATA[11.53±6.25 a ]]> <![CDATA[14.03±1.58 ab ]]> <![CDATA[14.90±1.90 ab ]]> Villus height / crypt depth <![CDATA[20.42±3.06 ab ]]> <![CDATA[19.53±0.74 ab ]]> <![CDATA[26.29±9.43 c ]]> <![CDATA[23.28±5.50 bc ]]> <![CDATA[23.21±0.89 bc ]]> <![CDATA[17.65±3.84 a ]]> <![CDATA[23.62±4.37 bc ]]> Cumulative infection mortality rate within one week 46.7％ 0 0 0 0 0 0
[0064] from Figure 7 It can be seen that compared with the golden pomfret fed with feed R, the relative abundance of the intestinal bacteria phylum Firmicutes of the golden pomfret fed with feeds S2 and S3 increased significantly, the relative abundance of the intestinal bacteria genera Ralstonia and Paraclostridium (probiotics) increased significantly, and the relative abundance of the intestinal bacteria species Ralstonia_insidiosa and Paraclostridium_bifermentans_ATCC_638 (probiotics) increased significantly. Compared with the golden pomfret fed with feed R, the relative abundance of the intestinal bacteria genus Escherichia_shigella (conditional pathogen) of the golden pomfret fed with feeds S2-S6 decreased significantly.
[0065] In summary, adding 0.2% curcumin to feed is beneficial to the growth performance and intestinal morphology of golden pomfret, and can also effectively reduce the prevalence of Cryptocaryon irritans. Adding 0.1% or 0.2% curcumin to feed can increase the relative abundance of probiotics (such as Ralstonia) in the intestines of golden pomfret and inhibit the relative abundance of conditional pathogens (such as Escherichia_shigella); in addition, adding 0.05%-1% curcumin to feed can effectively reduce the mortality of golden pomfret caused by Cryptocaryon irritans infection. Considering the growth, intestinal health and resistance to Cryptocaryon irritans infection of golden pomfret, the optimal curcumin supplementation dose in golden pomfret feed is recommended to be 0.2%.
[0066] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation methods of the present invention. For ordinary technical users in the relevant field, other different forms of changes or modifications can be made on the basis of the above description. It is not necessary and impossible to list all the implementation methods here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.
Claims
1. Application of curcumin in the preparation of products for killing Cryptocaryon irritans.
2. A product for killing Cryptocaryon irritans, characterized in that: The product includes curcumin.
3. The product according to claim 2, characterized in that The products include medicines, feed and pesticides.
4. A fish feed for preventing and treating Cryptocaryon irritans disease, characterized in that: The feed comprises 0.05 to 1 part of curcumin by weight.
5. The fish feed according to claim 4, characterized in that: In terms of weight, the feed also includes 20-30 parts of fish meal, 15-20 parts of chicken meal, 1.5-2 parts of rapeseed meal, 3-5 parts of blood meal, 5-6 parts of gluten powder, 5-7 parts of soybean meal, 12-13 parts of flour, 2 parts of starch, 2 parts of calcium hydrogen phosphate, 0.2 parts of choline, 2 parts of mineral mixture and 6.5-7.5 parts of fish oil.
6. The fish feed according to claim 4, characterized in that: The fish include all marine fishes including golden pomfret that can be infected with Cryptocaryon irritans.
7. A method for killing Cryptocaryon irritans in a water environment, characterized in that: Add curcumin or the product according to claim 1 to the water body to kill Cryptocaryon irritans.
8. The killing method according to claim 7, characterized in that: The added concentration of the curcumin is 20 to 200 μM; and the killing treatment time is 30 to 240 minutes.