Method for evaluating stress level of shellfish emaciation syndrome

Abstract

The invention discloses a method for evaluating the stress level of shellfish emaciation syndrome, and belongs to the technical field of aquaculture. According to the method for evaluating the stress level of the shellfish emaciation syndrome, the respiration rate is used as an indication index of the stress level of the shellfish emaciation syndrome, and the stress level of the shellfish emaciation syndrome is estimated by comparing the respiration rate of shellfish in a natural state in a culture sea area with the respiration rate of the shellfish under normal feeding. And farmers can conveniently take measures in advance to prevent and treat the shellfish emaciation syndrome. According to the method, the physiological indexes of the shellfish are used as indication indexes, so that the problems of low accuracy, high difficulty and incapability of directly reflecting the nutrition stress level of the shellfish in sea area nutrition monitoring are avoided, the blank of accurate evaluation of the filter-feeding shellfish marinating syndrome is filled, and an important technical support is provided for healthy culture of the shellfish.

Description

Technical Field

[0001] The invention relates to the technical field of aquaculture, and in particular to a method for evaluating the stress level of shellfish wasting syndrome. Background Art

[0002] Marine aquaculture shellfish is a high-quality source of "blue protein", but frequent large-scale mortality events seriously threaten the healthy development of the industry. The biological characteristics of open water aquaculture and filter feeding without feeding determine that shellfish are extremely susceptible to nutritional stress caused by insufficient feed in the sea area. In recent years, the nutritional conditions in the main offshore shellfish breeding areas have been under tremendous pressure, and farmed shellfish are generally in a sub-healthy state of "wasting syndrome". Wasting syndrome of shellfish is a systemic disease caused by insufficient nutrient intake, reduced metabolic and immune functions, disordered symbiotic flora, and reduced ability to resist external stimuli. A report pointed out that "during high temperatures in summer, the coupling of wasting syndrome caused by insufficient feed is an important cause of large-scale death of farmed shellfish". Assessing the stress level of shellfish wasting syndrome can facilitate the estimation of the risk of shellfish suffering from wasting syndrome, and facilitate farmers to take measures to prevent and control shellfish wasting syndrome in advance. It is in line with the current basic concept of shellfish disease prevention and control of "prevention first, prevention is more important than treatment", and can also provide an important reference for the formulation of aquaculture strategies such as translocation aquaculture.

[0003] However, since shellfish feed contains organic particles in addition to unicellular algae, accurate quantification is difficult and cannot truly reflect the nutritional status of the sea area, let alone the nutritional stress level of shellfish. Therefore, it is urgent to find a method that can accurately reflect the nutritional stress level of shellfish. Summary of the invention

[0004] The object of the present invention is to provide a method for evaluating the stress level of wasting shellfish syndrome to solve the problems existing in the above-mentioned prior art.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] One of the technical solutions of the present invention: Application of the respiratory rate value of shellfish in assessing the stress level of shellfish wasting syndrome.

[0007] Technical solution 2 of the present invention: A method for assessing the stress level of shellfish wasting syndrome, comprising the following steps:

[0008] Obtain the respiration rate A of shellfish samples in the culture sea area;

[0009] Obtain the respiration rate B of shellfish samples after normal feeding;

[0010] A t-test was performed on the respiration rate A and the respiration rate B, the p-value was recorded, and the wasting shellfish syndrome stress level was evaluated based on the p-value.

[0011] Furthermore, when p ≥ 0.05, it was not stressed, and when p < 0.05, it was stressed.

[0012] Normal feeding means feeding 6 to 8 times a day to maintain the density of algae bait in the aquaculture seawater at 2×10 5 ~4×10 5 cell / mL.

[0013] Technical solution 3 of the present invention: A method for assessing the stress level of shellfish wasting syndrome, comprising the following steps:

[0014] Obtain the respiration rate A of shellfish in the culture area;

[0015] Obtain the respiratory rate B of shellfish after normal feeding;

[0016] Perform a t test on the respiratory rate A and the respiratory rate B, and record the p value;

[0017] Calculate the mean of respiratory rate B and respiratory rate A, as well as the fold difference FC between the two means;

[0018] The stress level of shellfish wasting syndrome was evaluated based on p value and FC;

[0019] Wherein, FC = mean value of respiratory rate B / mean value of respiratory rate A.

[0020] Further, p ≥ 0.05, unstressed;

[0021] p < 0.05 and FC < 1.4, primary stress;

[0022] p < 0.05 and 1.4 ≤ FC < 1.8, moderate stress;

[0023] p < 0.05 and FC ≥ 1.8, severe stress.

[0024] Furthermore, the sample size of the shellfish sample is not less than 30; after obtaining the respiration rate A, the shellfish samples are fed normally in an indoor aquarium temporary culture system, and then the respiration rate B of the shellfish after normal feeding is obtained, and the water temperature and salinity of the aquarium system are kept consistent with those of the breeding sea area.

[0025] Furthermore, the normal feeding time is 10 days (when the respiration rate is relatively stable), the feeding bait is unicellular algae, and the density of unicellular algae in the aquaculture seawater is maintained at 2×10 5 ~4×10 5 cell / mL.

[0026] Furthermore, the unicellular algae include one or more of Nitzschia closterium, Chaetoceros hornwort and Phaeodactylum triangularis.

[0027] Furthermore, the method for obtaining the respiratory rate A and the respiratory rate B includes:

[0028] The shellfish sample is placed in a sealed measuring bottle filled with measuring seawater, and the dissolved oxygen data in the sealed measuring bottle is measured using a fiber optic oxygen meter every 3 to 10 seconds. The measurement is continued for 2 to 2.5 hours, and the slope of all dissolved oxygen values ​​is calculated to obtain the respiration rate of the shellfish sample;

[0029] The water temperature and salinity of the measured seawater are consistent with those of the aquaculture sea area.

[0030] Furthermore, when calculating the slope of all dissolved oxygen values, the non-changing dissolved oxygen values ​​of shellfish without breathing were eliminated, and the outliers above the upper quartile and below the lower quartile were eliminated to obtain the respiration rate of the shellfish samples.

[0031] Furthermore, before obtaining the respiration rate A and the respiration rate B, the shellfish samples are cleaned and surface attachments are removed, and the shellfish samples are kept out of water for no more than 2 hours.

[0032] Furthermore, a fiber optic oxygen meter (model: OXY-10ST, brand and origin: PreSens, Regensburg, Germany) was used to obtain the respiration rate.

[0033] Furthermore, the device used to obtain the respiration rate consists of a circulating water system, a sealed measuring bottle and an optical fiber oxygen meter; the sealed measuring bottle contains shellfish samples and seawater (seawater from the aquaculture area), is exhaust-sealed, and has a magnetic rotor at the bottom with a rotation speed of 200r / min to ensure that the dissolved oxygen in the bottle is evenly distributed; the sealed measuring bottle is placed in a circulating water system and the temperature is set to be consistent with that in the aquaculture area. The dissolved oxygen probe of the optical fiber oxygen meter is inserted into the sealed measuring bottle, and the dissolved oxygen data in the sealed measuring bottle is recorded every 3s, and the measurement is continuously performed for 2 to 2.5h.

[0034] The fourth technical solution of the present invention: a system for assessing the stress level of shellfish wasting syndrome, comprising a shellfish respiration rate data acquisition module and a shellfish wasting syndrome stress level assessment module;

[0035] The shellfish respiration rate data collection module is used to collect the respiration rate A of shellfish samples in the aquaculture sea area and the respiration rate B of shellfish samples after normal feeding;

[0036] The shellfish wasting syndrome stress level assessment module is used to assess the shellfish wasting syndrome stress level based on p value and FC;

[0037] Wherein, the p value is obtained by performing a t-test on the respiratory rate A and the respiratory rate B, and the FC is the multiple of the difference between the mean of the respiratory rate B and the mean of the respiratory rate A.

[0038] The present invention discloses the following technical effects:

[0039] The method for evaluating the shellfish wasting syndrome stress level of the present invention uses the respiration rate as an indicator of the shellfish wasting syndrome stress level. By comparing the respiration rate of shellfish under natural conditions in the aquaculture sea area with the respiration rate of shellfish under normal feeding, the shellfish wasting syndrome stress level is estimated, which is convenient for farmers to take measures to prevent and control shellfish wasting syndrome in advance.

[0040] The present invention adopts the physiological indicators of shellfish themselves as indicator indicators, avoiding the problems of low accuracy and difficulty of nutrition monitoring in sea areas and inability to directly reflect the nutritional stress level of shellfish, filling the gap in accurate evaluation of filter-feeding shellfish wasting syndrome, and providing important technical support for the healthy cultivation of shellfish. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] 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.

[0042] Figure 1 is a system for assessing the level of wasting shellfish syndrome stress;

[0043] Figure 2 Respiration rate of oysters treated for starvation stress;

[0044] Figure 3 The mortality rate of heat-shocked oysters after starvation stress. DETAILED DESCRIPTION

[0045] 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.

[0046] 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.

[0047] 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.

[0048] 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 invention description and examples are exemplary only.

[0049] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0050] In a first aspect, the present invention provides the use of respiratory rate values ​​of shellfish in assessing the stress level of shellfish wasting syndrome.

[0051] In a second aspect of the present invention, there is provided a method for assessing the stress level of wasting shellfish syndrome, comprising the following steps:

[0052] Obtain the respiration rate A of shellfish samples in the culture sea area;

[0053] Obtain the respiration rate B of shellfish samples after normal feeding;

[0054] A t-test was performed on the respiration rate A and the respiration rate B, the p-value was recorded, and the wasting shellfish syndrome stress level was evaluated based on the p-value.

[0055] Furthermore, when p ≥ 0.05, it was not stressed, and when p < 0.05, it was stressed.

[0056] In a third aspect, the present invention provides a method for assessing the stress level of wasting shellfish syndrome, comprising the following steps:

[0057] Obtain the respiration rate A of shellfish in the culture area;

[0058] Obtain the respiratory rate B of shellfish after normal feeding;

[0059] Perform a t test on the respiratory rate A and the respiratory rate B, and record the p value;

[0060] Calculate the mean of respiratory rate B and respiratory rate A, as well as the fold difference FC between the two means;

[0061] The stress level of shellfish wasting syndrome was evaluated based on p value and FC;

[0062] Wherein, FC = mean value of respiratory rate B / mean value of respiratory rate A.

[0063] Further, p ≥ 0.05, unstressed;

[0064] p < 0.05 and FC < 1.4, primary stress;

[0065] p < 0.05 and 1.4 ≤ FC < 1.8, moderate stress;

[0066] p < 0.05 and FC ≥ 1.8, severe stress.

[0067] In a specific embodiment of the present invention, the sample size of the shellfish sample is not less than 30;

[0068] After obtaining the respiration rate A, the shellfish samples are fed normally in an indoor aquarium temporary culture system, and then the respiration rate B of the shellfish after normal feeding is obtained. The water temperature and salinity of the aquarium system are consistent with those of the culture sea area;

[0069] The normal feeding time is 10 days, and the feeding bait is unicellular algae, and the density is not less than 2×10 5 ~4×10 5 cell / mL; the unicellular algae include one or more of Nitzschia closterium, Chaetoceros algae and Phaeochromis triangularis.

[0070] In a specific embodiment of the present invention, the method for obtaining the respiratory rate A and the respiratory rate B includes:

[0071] Place the shellfish sample in a sealed measuring bottle filled with seawater for measurement. Use a fiber optic oxygen meter to measure the dissolved oxygen data in the sealed measuring bottle every 3 to 10 seconds. Continuously measure for 2 to 2.5 hours, calculate the slope of all dissolved oxygen values, and obtain the respiration rate of the shellfish sample. The water temperature and salinity of the measured seawater should be consistent with those in the aquaculture area.

[0072] In a specific embodiment of the present invention, when calculating the slope of all dissolved oxygen values, the non-changing dissolved oxygen values ​​of shellfish that are closed and not breathing are eliminated, and the outliers above the upper quartile and below the lower quartile are eliminated to obtain the respiration rate of the shellfish samples.

[0073] In a specific embodiment of the present invention, before obtaining the respiration rate A and the respiration rate B, it also includes cleaning the shellfish samples to remove surface attachments, and the shellfish samples are kept out of water for no more than 2 hours.

[0074] In a specific embodiment of the present invention, a fiber optic oxygen meter (model: OXY-10ST, brand and origin: PreSens, Regensburg, Germany) is used to obtain the respiration rate.

[0075] In a specific embodiment of the present invention, the device used to obtain the respiration rate consists of a circulating water system, a sealed measuring bottle and an optical fiber oxygen meter; the sealed measuring bottle contains shellfish samples and seawater (seawater from the aquaculture area), is exhaust-sealed, and has a magnetic rotor at the bottom with a rotation speed of 200r / min to ensure that the dissolved oxygen in the bottle is evenly distributed; the sealed measuring bottle is placed in a circulating water system, and the temperature is set to be consistent with that in the aquaculture area. The dissolved oxygen probe of the optical fiber oxygen meter is inserted into the sealed measuring bottle, and the dissolved oxygen data in the sealed measuring bottle is recorded every 3s, and the measurement is continuously performed for 2 to 2.5h.

[0076] In a fourth aspect, the present invention provides a system for assessing the stress level of wasting shellfish syndrome, comprising a shellfish respiration rate data collection module and a shellfish wasting shellfish syndrome stress level assessment module;

[0077] Shellfish respiration rate data collection module, used to collect the respiration rate A of shellfish samples in the aquaculture sea area and the respiration rate B of shellfish samples after normal feeding;

[0078] The shellfish wasting syndrome stress level assessment module is used to assess the shellfish wasting syndrome stress level based on p-value and FC;

[0079] Wherein, the p value is obtained by performing a t-test on the respiratory rate A and the respiratory rate B, and FC is the multiple of the difference between the mean of the respiratory rate B and the mean of the respiratory rate A.

[0080] A systematic guide to assessing levels of wasting shellfish syndrome stress is available at Figure 1 .

[0081] The definition of FC value is:

[0082] 700 oysters were placed in an indoor aquarium temporary culture system. The water temperature, salinity, pH, dissolved oxygen content, ammonia nitrogen content, and nitrite content were consistent with those in the aquaculture area. They were temporarily cultured in the aquarium system for 10 days and fed with Nitzschia closterium 6 times a day to maintain a feed density of 2×10 5 ~4×10 5 On the 10th day, 30 oysters were taken, their surface biomass was brushed off, and their respiration rate was measured, which was recorded as respiration rate B. After the respiration rate measurement, the oysters were returned to the aquarium system, and the oysters were marked and recorded.

[0083] Then all oysters were starved for 44 days (no feeding). On the 0th (i.e. the 10th day of the feeding treatment), 3, 5, 7, 10, 13, 16, 20, 23, 30, 34, 37, and 44th day of the treatment, the respiratory rate was measured using 30 marked oysters, recorded as respiratory rates A0, A3, A5, A7, ..., A44. When an oyster died, 30 live oysters were used to make up the number (the live oysters that were starved at the same time) for subsequent respiratory rate measurements and were marked. After removing the non-changing dissolved oxygen values ​​and outliers of the oysters that were closed and not breathing, the respiratory rate results are shown in Figure 2. Figure 2 The respiratory rate A0 (respiratory rate B) is the respiratory rate under non-starvation stress, and the average respiratory rate is 3.5333×10 -4 mg / L·g·3s; A3, A5, A7, A10 are the initial respiration rates of starvation stress, with an average respiration rate of 2.6298mg / L·g·3s; A13, A16, A20 are the middle respiration rates of starvation stress, with an average respiration rate of 2.2466mg / L·g·3s; A23, A30, A34, A37, A44 are the late respiration rates of starvation stress, with an average respiration rate of 1.8865mg / L·g·3s. The respiration rate during non-starvation stress and the respiration rates in the three subsequent stages were significantly different by t test (p<0.05). The FC difference multiples between respiratory rate B and respiratory rates A3, A5, A7 and A10 are 1.27, 1.37, 1.34 and 1.39 respectively; the FC difference multiples between respiratory rate B and respiratory rates A13, A16 and A20 are 1.58, 1.61 and 1.73 respectively; the FC difference multiples between respiratory rate B and respiratory rates A23, A30, A34, A37 and A44 are 1.82, 1.85, 1.81, 1.91 and 1.99 respectively.

[0084] On the 0th, 3rd, 5th, 7th, 10th, 13th, 16th, 20th, 23rd, 30th, 34th, 37th, and 44th days of starvation treatment, 30 oysters were taken at each time point, placed in 42℃ seawater for 1 hour, then exposed to room temperature and placed in a separate tank of the original aquarium temporary system. The mortality rate was counted within the next 15 days. The oysters used for heat shock were no longer involved in the subsequent starvation test, nor were they used for respiratory rate determination. The mortality of oysters after heat shock is shown in Figure 3 The mortality rate in the early stage of starvation stress was 5.11% to 23.09%, with an average of 15.75%; the mortality rate in the middle stage of starvation stress was 39.18% to 51.27%, with an average of 44.67%; the mortality rate in the late stage of starvation stress was 59.13% to 87.17%, with an average of 75.8%.

[0085] Based on the three typical stage-by-stage changes in respiratory rate during starvation stress and the corresponding differences in heat shock mortality, combined with the threshold selection principle of "tight rather than loose", primary stress is defined as FC<1.4, intermediate stress is 1.4≤FC<1.8, and severe stress is FC≥1.8.

[0086] Example 1

[0087] A method for assessing the level of stress in wasting shellfish syndrome:

[0088] (1) In November 2022, 30 diploid long oysters cultured in Xiaoqingdao sea area of ​​Rushan were collected. The surface of the oysters was cleaned and the attachments were removed (the oysters were out of water for no more than 2 h), and the respiration rate A of the shellfish samples was obtained using a fiber optic oxygen meter (model: OXY-10ST, brand and origin: PreSens, Regensburg, Germany).

[0089] The device used to obtain the respiration rate consists of a circulating water system, a sealed measuring bottle and an optical fiber oxygen meter; the sealed measuring bottle contains the shellfish to be tested and seawater (seawater from the aquaculture area), is vented and sealed, and has a magnetic rotor at the bottom with a speed of 200r / min to ensure that the dissolved oxygen in the bottle is evenly distributed; the sealed measuring bottle is placed in a circulating water system, and the temperature is set to be consistent with that in the aquaculture area (the seawater temperature is 16.1℃ and the salinity is 29‰). The dissolved oxygen probe of the optical fiber oxygen meter is inserted into the sealed measuring bottle, and the dissolved oxygen data in the sealed measuring bottle is recorded every 3s. The measurement is continuously measured for 2h, and the respiration rate A is recorded.

[0090] (2) After the respiration rate A measurement was completed, 30 oysters were placed in an aquarium temporary culture system, and the water temperature and salinity were maintained at 16.1°C and 29‰, respectively. Nitzschia closterii was fed, and the density of Nitzschia closterii in the culture seawater was maintained at 2×10 5 ~4×10 5 cell / mL. After 10 days of continuous feeding, the oysters were taken out, the surface of the oysters was cleaned and the attachments were removed (the oysters were out of water for no more than 2 hours), and the respiration rate was measured using a fiber optic oxygen meter (model: OXY-10ST, brand and origin: PreSens, Regensburg, Germany).

[0091] The device used to obtain the respiration rate consists of a circulating water system, a sealed measuring bottle and an optical fiber oxygen meter; the sealed measuring bottle contains the shellfish to be tested and seawater (seawater from the aquaculture area), is vented and sealed, and has a magnetic rotor at the bottom with a speed of 200r / min to ensure that the dissolved oxygen in the bottle is evenly distributed; the sealed measuring bottle is placed in a circulating water system, and the temperature is set to be consistent with that in the aquaculture area (the seawater temperature is 16.1℃ and the salinity is 29‰). The dissolved oxygen probe of the optical fiber oxygen meter is inserted into the sealed measuring bottle, and the dissolved oxygen data in the sealed measuring bottle is recorded every 3s. The measurement is continuously measured for 2h, and the respiration rate B is recorded.

[0092] Table 1 Respiration rate measurement results

[0093]

[0094]

[0095] (3) Eliminate the non-changing dissolved oxygen values ​​of shellfish that are closed and do not breathe, and eliminate outliers (the calculation method of outliers is: Cmax = Q3 + k (Q3-Q1), Cmin = Q1-k (Q3-Q1);

[0096] Where Cmax is the estimated maximum value, Cmin is the estimated minimum value, Q3 is the upper quartile, Q1 is the lower quartile, and k is the abnormal parameter, where k = 1.5;

[0097] Values ​​above Cmax or below Cmin are outliers;

[0098] The eliminated data of respiratory rate A are: 0.0009, 0.0006, 1.3029, 1.4296;

[0099] The eliminated data of respiratory rate B are: 0.0008, 3.0256, 3.9882. A t-test was performed on respiratory rate A and respiratory rate B after eliminating the data, and p<0.05 was obtained;

[0100] Mean value of respiratory rate B / mean value of respiratory rate A = 1.61;

[0101] That is, p < 0.05 and 1.4 ≤ FC < 1.8, the tested oysters were under moderate stress level.

[0102] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. Application of shellfish respiration rate values ​​in assessing shellfish wasting syndrome stress levels.

2. A method for assessing the level of stress in wasting shellfish syndrome, characterized in that: The following steps are involved: Obtain the respiration rate A of shellfish samples in the culture sea area; Obtain the respiration rate B of shellfish samples after normal feeding; A t-test was performed on the respiration rate A and the respiration rate B, the p-value was recorded, and the wasting shellfish syndrome stress level was evaluated based on the p-value.

3. The method for assessing the level of wasting shellfish syndrome stress according to claim 2, characterized in that: When p≥0.05, it means no stress; when p<0.05, it means stress.

4. A method for assessing the level of stress in wasting shellfish syndrome, characterized in that: The following steps are involved: Obtain the respiration rate A of shellfish in the culture area; Obtain the respiratory rate B of shellfish after normal feeding; Perform a t test on the respiratory rate A and the respiratory rate B, and record the p value; Calculate the mean of respiratory rate B and respiratory rate A, as well as the fold difference FC between the two means; The stress level of shellfish wasting syndrome was evaluated based on p value and FC; Wherein, FC = mean value of respiratory rate B / mean value of respiratory rate A.

5. The method for assessing the level of wasting shellfish syndrome stress according to claim 4, characterized in that: p ≥ 0.05, unstressed; p < 0.05 and FC < 1.4, primary stress; p < 0.05 and 1.4 ≤ FC < 1.8, moderate stress; p < 0.05 and FC ≥ 1.8, severe stress.

6. The method for assessing the stress level of wasting shellfish syndrome according to any one of claims 2 to 5, characterized in that: The sample size of the shellfish sample is not less than 30 shellfish; and / or, After obtaining the respiration rate A, the shellfish samples are fed normally in an indoor aquarium temporary culture system, and then the respiration rate B of the shellfish after normal feeding is obtained. The water temperature, salinity, pH, dissolved oxygen content, ammonia nitrogen content, and nitrite content of the aquarium system are consistent with those of the breeding sea area.

7. The method for assessing the level of wasting shellfish syndrome stress according to claim 6, characterized in that: The normal feeding time is 10 days, the feeding bait is unicellular algae, and the density of unicellular algae in the aquaculture seawater is maintained at 2×10 5 ~4×10 5 cell / mL.

8. The method for assessing the stress level of wasting shellfish syndrome according to any one of claims 2 to 5, characterized in that: The method for obtaining the respiratory rate A and the respiratory rate B includes: The shellfish sample is placed in a sealed measuring bottle filled with measuring seawater, and the dissolved oxygen data in the sealed measuring bottle is measured using a fiber optic oxygen meter every 3 to 10 seconds. The measurement is continued for 2 to 2.5 hours, and the slope of all dissolved oxygen values ​​is calculated to obtain the respiration rate of the shellfish sample; The water temperature and salinity of the measured seawater are consistent with those of the aquaculture sea area.

9. The method for assessing the level of wasting shellfish syndrome stress according to claim 8, characterized in that: When calculating the slope of all dissolved oxygen values, the non-changing dissolved oxygen values ​​when the shellfish are closed and not breathing are excluded to remove outliers; The outlier value is calculated as follows: Cmax = Q3 + k (Q3 - Q1), Cmin = Q1 - k (Q3 - Q1); Where Cmax is the estimated maximum value, Cmin is the estimated minimum value, Q3 is the upper quartile, Q1 is the lower quartile, and k is the abnormal parameter, where k = 1.5; Values ​​above Cmax or below Cmin are outliers.

10. A system for assessing the level of stress in wasting shellfish syndrome, characterized in that: It includes a module for collecting data on shellfish respiration rate and a module for assessing the stress level of shellfish wasting syndrome; The shellfish respiration rate data collection module is used to collect the respiration rate A of shellfish samples in the aquaculture sea area and the respiration rate B of shellfish samples after normal feeding; The shellfish wasting syndrome stress level assessment module is used to assess the shellfish wasting syndrome stress level based on p value and FC; Wherein, the p value is obtained by performing a t-test on the respiratory rate A and the respiratory rate B, and the FC is the multiple of the difference between the mean of the respiratory rate B and the mean of the respiratory rate A.

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