Method for improving survival rate of penaeus monodon in storage and transportation process

Abstract

The invention discloses a method for increasing the survival rate of penaeus monodon in the storage and transportation process, and belongs to the field of alive-keeping transportation of aquatic products. The method comprises the steps of temporary rearing, gradient cooling dormancy treatment, oxygenation packaging and room-temperature storage. Wherein the cooling final temperature in the gradient cooling dormancy treatment step is 12 DEG C; a carrier used in oxygenation packaging is a foam box (the inner diameter is 390 mm * 270 mm * 200 mm; and the wall thickness is 20mm). By means of the method, physiological activities in the keep-alive process of the penaeus monodon can be effectively reduced, the stress response of the penaeus monodon can be reduced, the keep-alive survival rate of the penaeus monodon can be remarkably increased, meanwhile, equipment is simple, operation is easy, and certain economic benefits are achieved.

Description

Technical Field

[0001] The present invention relates to the field of live transportation of aquatic products, and particularly to a method for improving the survival rate of Penaeus monodon during storage and transportation. Background Art

[0002] Penaeus monodon grows fast, has a short breeding cycle, and a wide range of suitable temperature and salinity. It is one of the three major cultured shrimp species in the world, with a vast breeding area and is the main cultured shrimp species along the southern coast. Fresh shrimp is rich in nutrients such as protein and Omega-3 fatty acids. After its death, a series of changes will occur to the nutrients. For example, the oxidation and degradation of protein result in a decrease in its water-holding capacity; the content of saturated fatty acids increases significantly, and the content of polyunsaturated fatty acids decreases, etc., leading to the deterioration of its edible quality. In order to meet people's requirements for high-quality aquatic products, the development and optimization of live preservation technology have become a research hotspot at home and abroad.

[0003] Transporting aquatic products alive with water is the most common live transportation method, which has the advantages of convenient operation and transportation, large transportation volume, etc. Treating shrimp in a dormant state before transportation can improve its survival rate. Currently, the common dormancy treatment methods include low temperature and anesthetic treatment. However, there is a certain drug withdrawal period after using anesthetics, which is not conducive to economic benefits. The cooling methods can be divided into two types according to the cooling rate: instantaneous cooling (AC) and gradient cooling (GC). Instantaneous cooling has the advantages of simple operation and equipment. However, when the water temperature of the shrimp's living water area drops suddenly from the seasonal water temperature to the ecological ice point temperature, a strong stress response will occur, and in severe cases, it may lead to death; gradient cooling is a cooling method that slowly reduces the temperature of the transportation water body and the aquatic products to be transported through equipment at a certain cooling rate to make them enter a dormant state, and then carry out live transportation. By slowly cooling and domesticating the aquatic products, the stress stress caused by temperature changes can be effectively reduced; however, an inappropriate cooling rate will cause a strong stress response of the shrimp during storage and live transportation, which is not conducive to its live transportation. In addition, the ecological ice point temperatures of different species are different. Too high water temperature may lead to a short dormancy time and insufficient reduction of physiological metabolism, etc., and too low will cause its death.

[0004] Therefore, determining the ecological ice point temperature of Penaeus monodon and cooling it to the ecological ice point temperature at a suitable cooling rate to make it dormant is of great significance for improving the survival rate of Penaeus monodon. Summary of the Invention

[0005] The purpose of the present invention is to provide a method for improving the survival rate of Penaeus monodon during storage and transportation, so as to solve the problems existing in the above-mentioned prior art. By optimizing the gradient cooling conditions, the physiological and biochemical indexes of Penaeus monodon during storage and live preservation are effectively improved, and its survival rate is increased.

[0006] To achieve the above purpose, the present invention provides the following solutions:

[0007] The present invention provides a method for improving the survival rate of Penaeus monodon during storage and transportation, including the steps of temporary cultivation, cooling and dormancy treatment, oxygen filling and packaging, and room temperature storage;

[0008] The cooling and dormancy treatment is gradient cooling, and the gradient cooling includes the following steps: first, cooling at a rate of 4°C / h to 16°C, and then cooling at a rate of 2°C / h to the ecological ice point temperature.

[0009] Preferably, the conditions for the temporary cultivation are: salinity of 33‰, temperature of 25°C, pH value of 7.8 ± 0.1, and dissolved oxygen ≥ 5 mg / L.

[0010] Preferably, the temporary cultivation time is 1 - 2 h.

[0011] Preferably, the ecological ice point temperature is 12°C.

[0012] Preferably, after cooling to the ecological ice point temperature, the temperature is maintained and the shrimp are temporarily cultivated for 30 min to enable the Penaeus monodon to fully enter dormancy.

[0013] Preferably, the oxygen filling and packaging step includes filling high-purity oxygen into an oxygen filling bag or oxygenating with an oxygen pump, and temporarily cultivating in the dark.

[0014] Preferably, after oxygenating with the oxygen pump, the dissolved oxygen content ≥ 7 mg / L; and / or adding a small amount of temporary cultivation water to completely submerge the shrimp body.

[0015] Preferably, the container for oxygen filling and packaging is a foam box; the inner diameter of the foam box is 390 mm × 270 mm × 200 mm; and the wall thickness is 20 mm.

[0016] Preferably, each foam box contains 40 Penaeus monodon.

[0017] The present invention also provides the application of the above method in improving the storage survival rate of Penaeus monodon.

[0018] The present invention discloses the following technical effects:

[0019] The method provided by the present invention for enabling Penaeus monodon to enter dormancy by gradient cooling to improve the survival rate of the shrimp during storage and transportation selects an appropriate cooling rate for cooling and dormancy treatment in the cooling and dormancy treatment stage, which can effectively improve the physiological and biochemical indexes of Penaeus monodon during storage and transportation and preservation, and enhance its survival rate. Description of the Drawings

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings required for the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0021] Figure 1 It is a comparison chart of the pH value, dissolved oxygen content, ammonia nitrogen content and survival rate in the water environment during the preservation of Example 1, Comparative Example 2 and Comparative Example 3 of the present invention; A: pH value; B: dissolved oxygen content; C: ammonia nitrogen content; D: survival rate;

[0022] Figure 2 It is a chart of the determination results of the physiological and biochemical indexes of Penaeus monodon during the preservation of Example 1, Comparative Example 2 and Comparative Example 3 of the present invention; A: blood glucose content; B: lactic acid (LA) content; C: lactic dehydrogenase (LDH) activity; D: alkaline phosphatase (ALP) activity; E: catalase (CAT) activity; F: superoxide dismutase (SOD) activity;

[0023] In the figure, the upper and lower abscissas are distinguished by different colors: red represents the time gradient of the WC group; black represents the time gradient of the GC and AC groups; the abscissa corresponds to the color of the broken line. Detailed implementation manners

[0024] Now, the various exemplary implementation manners of the present invention will be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, characteristics and implementation schemes of the present invention.

[0025] It should be understood that the terms described in the present invention are only for describing specific implementation manners and are not used to limit the present invention. In addition, for the numerical ranges in the present invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any intermediate value within any stated value or stated range, as well as each smaller range between any other stated value or intermediate value within the stated range, is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded from the range.

[0026] Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the art to which the present invention pertains. Although the present invention only describes preferred methods and materials, any methods and materials similar or equivalent to those described herein can 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 related to the documents. In case of conflict with any incorporated document, the content of this specification shall prevail.

[0027] Without departing from the scope or spirit of the present invention, various improvements and changes can be made to the specific embodiments of the specification of the present invention, which will be obvious to those skilled in the art. Other embodiments obtained from the specification of the present invention will be obvious to those skilled in the art. The specification and examples of the present invention are merely exemplary.

[0028] Regarding the use of "comprising", "including", "having", "containing", etc. in this article, they are all open-ended terms, meaning including but not limited to.

[0029] Example 1 A method for improving the survival rate of Penaeus monodon during storage and transportation by making Penaeus monodon dormant through gradient cooling includes the following steps:

[0030] (1) Temporary rearing: Purchase Penaeus monodon with roughly the same size and vitality from Haizhihui Seafood Market in Meilan District, Haikou City, and temporarily rear them in temporary rearing water with a salinity of 33‰, a temperature of 25°C, a pH value of 7.8 ± 0.1, and a dissolved oxygen ≥ 5 mg / L for 1 - 2 h.

[0031] (2) Cooling and dormancy treatment: After the Penaeus monodon are temporarily reared, use a circulating chiller to first cool them to 16°C at a cooling rate of 4°C / h, and then cool them to the ecological ice point of 12°C at a cooling rate of 2°C / h. After reaching the ecological ice point, maintain the temperature and temporarily rear them for 30 min to make them fully enter dormancy.

[0032] (3) Oxygen filling and packing: Use 4 foam boxes of the same size (inner diameter 390 * 270 * 200; wall thickness 20 mm). Put 40 Penaeus monodon in each foam box, add a small amount of temporary rearing seawater (covering the shrimp body), pack them with an oxygen-filled bag and fill with high-purity oxygen (oxygen concentration ≥ 99.8%), quickly tie the bag mouth tightly with a rubber band, and cover it with a black plastic bag for shading. The 4 plastic boxes are respectively marked as the 2h, 4h, 6h, and 8h live preservation groups.

[0033] (4) Storage: Place the 4 plastic boxes in a room temperature environment. After reaching the established time of the live preservation group, conduct survival rate statistics and measure 6 physiological and biochemical indexes, namely blood glucose, lactic acid (LA) content, lactate dehydrogenase (LDH) activity, alkaline phosphatase (ALT) activity, catalase (CAT) activity, and superoxide dismutase (SOD) activity in the hemolymph and hepatopancreas using a commercial kit.

[0034] Example 2 A method for improving the survival rate of Penaeus monodon during storage and transportation by making Penaeus monodon dormant through gradient cooling

[0035] includes the following steps:

[0036] (1) Temporary rearing: Purchase Penaeus monodon with roughly the same size and vitality from Haizhihui Seafood Market in Meilan District, Haikou City, and rear them in temporary rearing water with a salinity of 33‰, a temperature of 25°C, a pH value of 7.8±0.1, and a dissolved oxygen of ≥5 mg / L for 1-2 h.

[0037] (2) Cooling and dormancy treatment: After the temporary rearing treatment of Penaeus monodon, use a circulating chiller to first cool it to 16°C at a cooling rate of 4°C / h, and then cool it to 10°C, 11°C, 12°C, 13°C, 14°C, and 15°C at a cooling rate of 2°C / h respectively. After reaching the specified temperature, maintain the temperature and rear it for 30 min to make it fully enter dormancy.

[0038] (3) Oxygen filling and packing: Foam boxes (inner diameter 390 mm×270 mm×200 mm; wall thickness 20 mm), put 40 Penaeus monodon in each foam box, add a small amount of temporary rearing seawater (covering the shrimp body), then use an oxygen pump to fill with oxygen, and cover with a black plastic bag to shade, and mark the 8-h survival group.

[0039] (4) Storage: Place the foam boxes in a room temperature environment, and count the survival rate after reaching the established time of the survival group.

[0040] Comparative Example 1

[0041] Comparative Example 1 is the same as Example 1, the only difference is that the shrimps are cooled to 10°C, 11°C, 12°C, 13°C, 14°C, and 15°C respectively by the method of instantaneous cooling, then use an oxygen pump to fill with oxygen, and count the survival rate after 8 h.

[0042] Comparative Example 2

[0043] Comparative Example 2 is the same as Example 1, the only difference is that in the cooling and dormancy treatment step, the Penaeus monodon after the end of temporary rearing is directly transferred into seawater at 12°C for dormancy.

[0044] Comparative Example 3

[0045] Comparative Example 3 is the same as Example 1, the difference is that after the end of temporary rearing, skip the cooling treatment step and directly carry out oxygen filling and packing; the survival time is reduced to 4 h, and 4 plastic boxes are marked as the 1-h, 2-h, 3-h, and 4-h survival groups respectively.

[0046] Survival rate statistics and determination of physiological and biochemical indexes

[0047] 1. The survival rates of Penaeus monodon after 8 hours of storage and transportation in Example 1, Example 2, Comparative Example 1, and Comparative Example 2 were measured, and the results are shown in Table 1. It can be seen from the comparison between Example 2 and Comparative Example 1 that under instantaneous cooling treatment, the survival rate of Penaeus monodon has a mutation point (i.e., the ecological sub-zero temperature point) at 13°C, that is, the survival rate of Comparative Example 1 decreased from 70% to 30%; while after gradient cooling domestication (such as in Example 2), the ecological sub-zero temperature point of Penaeus monodon decreased to 12°C, enabling it to be transported alive at a lower temperature. It can be seen from Example 1 that the survival rate of Penaeus monodon after 8 hours of oxygen-supplemented live preservation under gradient cooling treatment can still remain above 75%. Compared with Comparative Example 2, the survival rate increased by 167.86%.

[0048] Table 1 Survival rates of Penaeus monodon after 8 hours of live preservation in Example 1, 2 and Comparative Examples 1, 2

[0049]

[0050]

[0051] 2. During the live preservation process of Example 1 (GC group; hereinafter represented by GC), Comparative Example 2 (AC group; hereinafter represented by AC), and Comparative Example 3 (WC group; hereinafter represented by WC), the pH value of the water environment ( Figure 1 A), dissolved oxygen content ( Figure 1 B), ammonia nitrogen content ( Figure 1 C), and survival rate ( Figure 1 D) were measured, and the results are shown in Figure 1 . The results of dissolved oxygen content are shown in Figure 1 A. The dissolved oxygen consumption rate of the GC group (Example 1) was significantly lower than that of the AC group (Comparative Example 2). Penaeus monodon after low-temperature domestication has stronger cold adaptation ability than Penaeus monodon under acute cold stress, with weakened physiological metabolism activities and reduced energy demand for aerobic metabolic pathways; while the dissolved oxygen content in both groups was < 5 mg / L in the middle and late stages of live preservation, which also indicates that Penaeus monodon may be under hypoxic stress in the middle and late stages of live preservation, and metabolic pathways, stress response, etc. may change accordingly. The results of ammonia nitrogen content are shown in Figure 1 B. From the accumulation of ammonia nitrogen, due to the closed storage and transportation environment, the generated ammonia nitrogen accumulates in the water environment, and there is a significant upward trend in the ammonia nitrogen accumulation in both groups; the lower survival rate of the AC group compared to the GC group and the sharp drop at 4 - 6 hours are the main reasons for the AC group to always maintain a higher ammonia nitrogen content. The results of the survival rate are shown in Figure 1 D. At the end of the final live preservation, only 28% of the AC group survived.

[0052] 3. During the live preservation process of Example 1 (GC group), Comparative Example 2 (AC group), and Comparative Example 3 (WC group), the blood glucose ( Figure 2 A) and lactic acid (LA) content ( Figure 2in B), lactate dehydrogenase (LDH) ( Figure 2 in C) were measured. The blood glucose content in the hemolymph of Penaeus monodon in the WC group decreased significantly from 0 to 2 h, and in the GC and AC groups decreased significantly from 0 to 4 h. The blood glucose in all three groups showed a gradually decreasing trend. Among them, the decrease rate in the WC group was 67.4%. This was mainly because the Penaeus monodon was not treated with dormancy and would be affected by various stress factors during packing, storage, and transportation, resulting in different degrees of stress responses, which led to the decrease in the blood glucose content in the hemolymph. The decrease rates in the GC and AC groups were 33.2% and 42.4% respectively. The blood glucose content decreased gradually under both treatments, indicating that Penaeus monodon was still carrying out metabolic activities such as aerobic respiration and anaerobic respiration at low temperatures to maintain normal physiological metabolism. However, the decrease rates in both groups were significantly lower than that in the WC group, mainly because the temperature of the environmental water would affect the respiratory metabolism-related abilities of Penaeus monodon. After low-temperature dormancy, the physiological activities of Penaeus monodon decreased, the activities of energy metabolism-related enzymes such as succinate dehydrogenase decreased, and the metabolic ability decreased accordingly, resulting in a slower consumption of blood glucose. At 2 - 3 h in the WC group and 4 - 6 h in the GC and AC groups, there was a significant increase in blood glucose. The increase rates in the WC group and AC group were 104.7% and 90.1% respectively, indicating that hyperglycemia occurred in both groups of Penaeus monodon, which was one of the factors leading to the death of Penaeus monodon during storage and transportation. The increase rate of blood glucose in the GC group was 20%. It was possible that under long-term stress, Penaeus monodon decomposed and metabolized some of its internal proteins and lipids to provide more ATP to cope with low-temperature stress. Some metabolites such as α-keto acids and glycerol could enter the gluconeogenesis pathway to produce blood glucose. In the later stage of live preservation, the blood glucose content in all three groups decreased significantly. The Penaeus monodon gradually adapted to the environmental conditions, established a new physiological metabolism balance, accelerated the consumption of blood glucose in the hemolymph, activated the metabolic compensation mechanism, and provided more energy for the body to cope with environmental stress conditions.

[0053] The results of LA content are as Figure 2 in B and Figure 2As shown in C, within 0 - 6 h (0 - 3 h for the WC group), the LA content and LDH activity of the three groups of Penaeus monodon showed an upward trend. The LDH activity and LA content of the GC group were significantly higher than those of the other two groups, indicating that the main pathway of energy metabolism in Penaeus monodon after GC treatment shifted to anaerobic metabolism, and the ATP produced through this pathway was less than that of aerobic metabolism. This shows that the physiological metabolic activities of Penaeus monodon weakened after low - temperature acclimation, and the energy demand decreased. It can also be seen from the consumption of blood glucose that the AC group consumed more than the GC group. This is because under acute low - temperature stress, pathways related to stress resistance such as humoral immunity, cellular immunity, endoplasmic reticulum stress, and apoptosis increased significantly, and more ATP synthesis was required to maintain survival. From 6 - 8 h (3 - 4 h for the WC group), the LDH activity and LA content of the three groups decreased significantly. This may be because lactic acid accumulated in tissues and was released into the hemolymph, or it may be that through clearance pathways such as excretion and oxidative decomposition, part of the large amount of LA produced by anaerobic respiration was consumed, bringing the body's lactic acid content back to normal levels.

[0054] 4. During the preservation process of Penaeus monodon in Example 1 (GC group), Comparative Example 2 (AC group), and Comparative Example 3 (WC group), the alkaline phosphatase (ALP) ( Figure 2 as shown in D), catalase (CAT) ( Figure 2 as shown in E), and superoxide dismutase (SOD) ( Figure 2 as shown in F) activities were measured. In the early stage of preservation, the ALP activities of the three groups of Penaeus monodon increased. For the GC group and the AC group, it may also be because under cold stress, the permeability of the cell membrane increased, the immune system was activated, and the ALP activity was stimulated to increase. Among them, the decrease in ALP activity in the WC group from 2 - 4 h may be due to the fact that the increase in plasma cortisol content has a certain inhibitory effect on the ALP activity. The ALP activity in the WC group decreased significantly from 2 - 4 h, which means that under continuous stress, the permeability of the hepatopancreas cell membrane of Penaeus monodon increased, ALP was released into the hemolymph, and the ALP activity in the hepatopancreas decreased; under the conditions of further deterioration of dissolved oxygen and ammonia nitrogen content in the water environment and exhaustion of blood glucose, irreversible cell damage impaired the liver function of Penaeus monodon, and it could no longer synthesize and release sufficient ALP and other immune - related enzymes to participate in the regulation of the body's immune response. The ALP activity in the AC group first increased significantly and then decreased significantly from 4 - 8 h. Acute cold stress induced a large amount of ROS and free radicals in mitochondria, and a large number of physiological processes such as inflammatory reactions, cellular immunity, and apoptosis were activated, resulting in an increase in ALP activity. However, a certain degree of liver damage also occurred in the later stage of preservation, reducing the synthesis and secretion of ALP. The ALP activity in the GC group increased significantly in the later stage of preservation. It shows that Penaeus monodon after low - temperature acclimation can still perform normal physiological functions of the liver under environmental stress of water environment deterioration, regulate the immune response by adjusting the activities of enzymes such as ALP, and resist the invasion of external pathogens.

[0055] The CAT activities in the AC and WC groups increased significantly, while the CAT activity in the GC group decreased significantly. In the early stage of maintaining the activity, due to stress such as physical contact and low temperature, a large amount of reactive oxygen species (ROS) such as superoxide anion (O 2- ) and hydrogen peroxide (H2O2) were rapidly produced in the Penaeus monodon. At the same time, the immune system in the body was activated, and immune cells such as hemolymphocytes might also produce ROS during the immune response. The SOD activity increased to cope with the oxidative stress of the Penaeus monodon, catalyzing O 2- to be converted into H2O2 and oxygen. As a key enzyme for scavenging H2O2 in the body, the AC group and the WC group up-regulated its activity to catalyze the conversion of H2O2 into water and oxygen, reducing the oxidative damage of cells. The decrease in the CAT activity in the GC group might be caused by the antagonistic effect of the up-regulation of other related proteins in the antioxidant system such as glutathione peroxidase and peroxiredoxin. For example, continuous ammonia nitrogen stress would lead to the up-regulation of the expression of peroxisomes in the Penaeus monodon. After 12 hours of anhydrous transportation of the Penaeus monodon after low-temperature acclimation, the activities of glutathione peroxidase and peroxidase increased significantly. The SOD and CAT activities of the Penaeus monodon in the WC group at 2 - 4 hours and in the AC group at 6 - 8 hours decreased, probably because as the maintenance of activity proceeded, the ammonia nitrogen content continued to increase, interfering with the energy metabolism of the Penaeus monodon and exacerbating the oxidative stress. The continuous oxidative stress caused the accumulation of ROS to exceed the scavenging and detoxifying ability of the antioxidant system of the Penaeus monodon itself. Under the stress of high-concentration ROS, the active centers of CAT and SOD might be oxidized and damaged, and the hepatopancreas would also show tissue damage under continuous stress, resulting in the inhibition of the synthesis of CAT and SOD. The SOD and CAT activities in the GC group increased at 4 - 8 hours, indicating that after the Penaeus monodon was treated with low-temperature acclimation, the damage caused by oxidative stress was greatly reduced. Under environmental stresses such as the increase in environmental temperature and ammonia nitrogen content in the later stage of maintaining the activity, it could still normally synthesize antioxidant-related enzymes to scavenge ROS and protect the body from oxidative damage.

[0056] Effects of two different cooling dormancy treatment methods, gradient cooling and instantaneous cooling, on the proteomics of Penaeus monodon

[0057] Experimental design: It was carried out according to the treatment methods and steps of Penaeus monodon in Example 1. The difference from Example 1 was only that two experimental groups, gradient cooling (GC group) and instantaneous cooling (AC group), were set. After using the two methods of gradient cooling and instantaneous cooling to cool the Penaeus monodon into dormancy and temporarily raise them (30 min), muscle sampling and proteomics research were carried out on them immediately.

[0058] Table 2 Target differentially expressed proteins in the muscles of GC and AC

[0059]

[0060]

[0061] Note: * indicates significant difference (P < 0.05); ** indicates extremely significant difference (P < 0.01).

[0062] The differential proteins in the muscle tissues of Penaeus monodon under two treatments were screened and analyzed as shown in Table 2. After GC treatment, the aerobic respiration of Penaeus monodon weakened, and the anaerobic respiration increased; the ATP synthesis and decomposition and stress response weakened; the immune function enhanced. Under GC treatment, glyceraldehyde-3-phosphate dehydrogenase in the GC group was up-regulated, providing energy for the body's metabolic activities by enhancing anaerobic respiration. Under AC treatment, proteins related to oxidative phosphorylation such as cytochrome c subunit were up-regulated, and Penaeus monodon chose to enhance aerobic respiration to provide a large amount of energy for the body, and the expression of ATP synthesis-related proteins such as ATP synthase and ADP / ATP translocase was up-regulated to enhance the oxidative phosphorylation pathway. Since the physiological and metabolic activities of Penaeus monodon under AC treatment were stronger than those in the GC group, more ROS and free radicals were generated in metabolic processes such as ETC, thus triggering an enhanced stress response in the body and the up-regulation of stress-related proteins such as Hsp. After low-temperature acclimation, Penaeus monodon showed a more perfect immune defense, adapting to the cold environment and jointly resisting pathogen invasion through the differential expression of 17 immune-related proteins.

[0063] In summary, the present invention improves the temperature reduction conditions in the dormancy treatment link of Penaeus monodon, regulates the water environment, physiological and biochemical indexes, stress response, immune function, etc. during its live preservation process, and improves the survival rate of Penaeus monodon during live preservation. At the same time, the equipment requirements are simple and easy to operate, easy to apply in practice, and pollution-free, which is an efficient method to improve the survival rate of shrimp.

[0064] The embodiments described above are only descriptions of the preferred embodiments of the present invention, and do not limit the scope of the present invention. Without departing from the design spirit of the present invention, various deformations and improvements made by those of ordinary skill in the art to the technical solutions of the present invention shall fall within the protection scope determined by the claims of the present invention.

Claims

1. A method for improving the survival rate of Penaeus monodon during storage and transportation, characterized in that, It includes steps of temporary rearing, cooling and dormancy treatment, oxygen filling and packaging, and room temperature storage; The cooling and dormancy treatment is gradient cooling, and the gradient cooling includes the following steps: first, cool down to 16°C at a cooling rate of 4°C / h, and then cool down to the ecological ice point at a cooling rate of 2°C / h.

2. The method according to claim 1, wherein The conditions for the temporary rearing are: salinity of 33‰, temperature of 25°C, pH value of 7.8 ± 0.1, and dissolved oxygen ≥ 5 mg / L.

3. The method according to claim 1, wherein The time for the temporary rearing is 1 - 2 h.

4. The method according to claim 1, characterized in that The ecological ice point is 12°C.

5. The method according to claim 1, characterized in that After cooling down to the ecological ice point, maintain the temperature and temporarily rear for 30 min to enable the Penaeus monodon to fully enter dormancy.

6. The method according to claim 1, wherein The oxygen filling and packaging step includes filling high-purity oxygen into an oxygen filling bag for packaging or using an oxygen pump for oxygenation, and temporarily rearing in the dark.

7. The method according to claim 6, wherein After oxygenation by the oxygen pump, the dissolved oxygen content ≥ 7 mg / L; and / or add a small amount of temporary rearing water to completely submerge the shrimp body.

8. The method according to claim 1, characterized in that The container for oxygen filling and packaging is a foam box; the inner diameter of the foam box is 390 mm × 270 mm × 200 mm, and the wall thickness is 20 mm.

9. The method according to claim 8, wherein Each foam box contains 40 Penaeus monodon.

10. Application of the method according to any one of claims 1 - 9 in improving the storage survival rate of Penaeus monodon.

Images