JP2014161239A - Hibernation induction method and anhydrous transportation method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hibernation induction method of fishes that can induce fishes in a pseudo-hibernation state at low cost, and enables the fishes to live at a high revival rate, even if being left in air 24 hours or more under anhydrous environment, and to provide an anhydrous transportation method.SOLUTION: A hibernation induction method includes the steps of: farming fishes at rest during a first time τin an aquarium maintained in a rest farming temperature T; quenching the fishes, by moving the fishes to the aquarium maintained in a cold acclimatization temperature Tlower than the rest farming temperature T, after the lapse of the first time τ; inducing the fishes in a pseudo-hibernation state by bringing the fishes into the acclimatization at rest during a second time τin the aquarium maintained in the cold acclimatization temperature T, and furthermore continuing the acclimatization; and moving the fishes to a shipping container maintained at an oxygen concentration of 60% or more after the lapse of the second time τand conveying the shipping container to transport the fishes in a pseudo-hibernation state under anhydrous environment.

Description

  The present invention relates to a hibernation-inducing method for suppressing a part of motor functions such as physiological metabolism function of live fish to make it a pseudo-hibernation state, and transporting the fish in the pseudo-hibernation state while not containing water. The present invention relates to an anhydrous transport method (seawater-free transport method) for transporting in a container.

  When treating fish as food, the value of the product is freshness, and there are two ways to maintain the freshness and transport it to consumers: one that is transported as live fish and one that is transported at a low temperature such as frozen. There is something to do. In particular, in restaurants and restaurants that cook and provide fish, stores equipped with aquariums and ginger to store and display fish alive to provide fresh and delicious fish dishes Is increasing. In order to deliver fish alive, various transport technologies have been developed for the purpose of preventing damage to the fish during transport and maintaining freshness.

  Conventionally, live fish has been transported by ships and vehicles equipped with ginger, but generally requires 1.5 to 10 times the weight of live fish, and an aeration device is also required. Therefore, there was a problem that the transportation cost was high. For example, when carrying one flounder, it was necessary to carry a ginger filled with 3 to 3.5 kilograms of seawater at the same time. In addition, a ginger according to the type and characteristics of the fish is necessary, and it is difficult to transport all the fish in the same way. In addition, the fish body is damaged due to collisions between fish and ginger during transportation, food problems during transportation for a long time, and the fish itself becomes stressed and fatigued due to seawater temperature fluctuation during transportation and so on. Therefore, it is not always easy to maintain a freshly caught state. If the method of transporting fish is not appropriate, in the worst case, the fish in the ginger may be killed, so there is a problem of deterioration in quality and yield.

  Therefore, there is a demand for an anhydrous transport method (seawater-free transport method) that can prevent deterioration during transport while keeping fish alive, can withstand transport for a long time of 24 hours or more, and can transport a large amount. In other words, the motor function such as physiological metabolism function of live fish is reduced or suppressed by some method to induce a pseudo-hibernation state (cold coma state), and the life support function such as respiratory organs is sufficiently maintained and narrow It is sufficient that anhydrous transport can be performed in space, and then resuscitation can be performed at a high resuscitation rate.

For example, the anhydrous transport technology for fish is based on the theory of four stages: (a) resting, (b) cool-down, (c) low temperature acclimation, and (d) standing in the air, as shown in FIG. (See Non-Patent Document 1). The rest-breeding stage at times t _{0 to} t ₁ in the conventional theory is a first stage for removing the stress of fish at the water temperature T ₁ in preparation for cooling by the next cool-down stage. The cool-down stage at times t _{1 to} t ₂ is a _second stage in which the fish tank containing the fish is gradually cooled (slowly cooled) from the water temperature T ₁ to the water temperature T ₁ to induce a pseudo-hibernation state. Although fish become pseudo-hibernating when the body temperature decreases, fish that are variable temperature animals (exothermic animals) cannot be adapted to a sudden drop in water temperature according to conventional common general knowledge, and the water temperature in the tank is adjusted to the water temperature T _1. if suddenly lowered in temperature T ₂ required for the pseudo-hibernation state fish it has been considered will die from (see non-Patent Document 2.). The low temperature acclimation stage at times t _{2 to} t ₃ is a _third stage in which the fish is acclimated to a low temperature at the water temperature T ₂ to realize a pseudo-hibernation state. The air leaving stage after time t ₃ is the fourth stage for transporting fish in an anhydrous state.

  The slow cooling in the second stage slows the movement of the fish in the aquarium, gradually weakens the physiological effect, and enters a pseudo-hibernation state. Pseudo-hibernating fish breathe air instead of underwater breathing and prolong life with minimal physiological action, so this pseudo-hibernating state can be used to transport anhydrous in a box that does not contain any water . After anhydrous transport in the pseudo-hibernation state, when the fish is returned to water at a restaurant or restaurant, the fish wakes up from the pseudo-hibernation state.

  However, in the method described in Non-Patent Document 1, the longest record of anhydrous life in the fourth stage was at most 27 hours. In addition, the resuscitation rate of flounder after anhydrous storage for 20 hours or less is about 50 to 60%, and when the anhydrous survival time exceeds 24 hours, the resuscitation rate is about 33%, which is described in Non-Patent Document 1. This method has the disadvantage that the yield of resuscitation is low and the quality of live fish is also deteriorated.

Furthermore, in the method based on the basic principle using the cool-down stage by slow cooling as described in Non-Patent Document 1, a temperature control device is provided to perform the cool-down stage at times t _{1 to} t ₂ . and it requires an expensive refrigerated water tank, operating costs such as electricity bills and personnel expenses for capital investment and operation of refrigerated water tank to the refrigeration water tank is also required, further, cool between the time t ₁ ~t ₂ There are various inconveniences that a down time is required (see Patent Document 1). In particular, power consumption is required to be reduced in a serious power situation.

  For example, in the method for guiding marine organisms to an artificial hibernation state described in Patent Document 1, the temperature of the seawater is lowered step by step at intervals of 1 ° C., and further, the temperature of each step that is successively lowered, that is, 12 ° C., 11 ° C. At 10 ° C and 9 ° C, the temperature of seawater containing marine organisms is gradually expanded to 20 minutes, 30 minutes, 40 minutes, and 50 minutes, and the temperature is gradually increased to 20 minutes, 30 minutes, 40 minutes, and 50 minutes. I was leading to the state. In the case of halibut, although it is finally cooled to below freezing point (−) 0.2 ° C., the total hibernation induction time required about 20 hours (see paragraphs [0058] to [0062] of Patent Document 1). Column).

JP 2008-188008 A

Michifumi Kimizuka and two others, “Application of low-temperature anesthesia to transporting seawater-free fish”, Journal of Low-temperature Biotechnology, Society for Low-temperature Biotechnology, October 2012, Vol. 58, No. 2, p. 201-205 Tamura Tadashi, "Effects of changes in the surrounding environment on fishes: Effects of sudden changes in water temperature on various fishes, especially on cold and heat coma", Nissui Magazine, 1944, Vol. 12, No. 6, p. 204

 The present invention does not require the use of an expensive refrigerated water tank equipped with a temperature control device, can guide fish to a pseudo-hibernation state at low cost, and makes use of this pseudo-hibernation state for over 24 hours in an anhydrous environment. It is an object of the present invention to provide a method for inducing hibernation of fish, and a method for anhydrous transport of fish using this hibernation induction method, in which fish can survive at a high resuscitation rate.

  In order to achieve the above object, the first aspect of the present invention includes (a) a step of rearing fishes in a water tank maintained at a resting rearing temperature for a first time, and (b) second After the passage of time 1, the stage of rapidly cooling the fish by moving the fish into an aquarium maintained at a low acclimation temperature lower than the resting culture temperature; and (c) the aquarium maintained at the low acclimation temperature. Among them, the gist of the present invention is a hibernation induction method including a step of acclimating a fish for a second time and inducing a fish into a pseudo-hibernation state and continuing the habituation.

 According to a second aspect of the present invention, (a) a stage in which a fish is kept at rest for a first time in a water tank maintained at a resting temperature, and (b) after the first time has elapsed, the fish By cooling the fish into a tank maintained at a low acclimation temperature below the resting culture temperature, and (c) the fish in a tank maintained at a low acclimation temperature for a second time, Inducing the fish to a pseudo-hibernation state by further acclimatization at rest, and (d) after the second time has passed, move the fish to the shipping container and move the inside of the shipping container The present invention provides an anhydrous transport method including a step of transporting a fish in a state of pseudo-hibernation in an anhydrous environment by transporting a transport container while maintaining an oxygen concentration of 60% or more and a low acclimation temperature. To do.

  According to the present invention, it is not necessary to use an expensive refrigerated water tank equipped with a temperature control device, fish can be guided to a pseudo-hibernation state at low cost, and this pseudo-hibernation state is utilized for 24 hours in an anhydrous environment. As described above, it is possible to provide a method for inducing hibernation of fish and a method for anhydrous transport of fish using this hibernation induction method, in which fish can survive at a high resuscitation rate even if left in the air.

It is a temperature diagram explaining the outline of the hibernation induction | guidance | derivation method and anhydrous transport method which concern on embodiment of this invention using the relationship between the temperature of each step, and time. FIG. 2 (a) is a diagram schematically illustrating the schematic state of the aquarium used in the stage of calmly raising fish in the hibernation induction method and the anhydrous transport method according to the embodiment of the present invention. b) is a diagram schematically illustrating a schematic state of an aquarium used in a stage of acclimatizing fish to be in a simulated hibernation state in the hibernation induction method and the anhydrous transport method according to the embodiment of the present invention. It is. It is a figure which illustrates typically the outline of the structure of the transport preparation stage of the container for transport in the anhydrous transport method which concerns on embodiment of this invention. It is a temperature diagram explaining the hibernation induction | guidance | derivation method using the slow cooling method which concerns on a prior art using the relationship between the temperature of each step, and time.

  Next, embodiments of the present invention will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, it should be noted that the drawings are schematic, and the relationship between the thickness and the planar dimensions, the ratio of the thickness of each layer, and the like are different from the actual ones. Therefore, specific thicknesses and dimensions should be determined in consideration of the following description. Moreover, it is a matter of course that portions having different dimensional relationships and ratios are included between the drawings.

  In addition, the embodiment of the present invention described below will exemplarily explain the case of Japanese flounder that has a low resuscitation rate compared to carp and crucian carp that have been studied for anhydrous transport as a typical example. The technical idea of the invention is not limited to the case of flounder. Explaining the case of Japanese flounder with a low resuscitation rate. It is easy for those skilled in the art that the hibernation induction method and the anhydrous transport method according to the embodiment of the present invention can be applied to various fish that hibernate or pseudo-hibernate, such as Chaylor Grouper, Sugiara, Loach, Catfish You can understand. And in embodiment of this invention, although the low temperature acclimation temperature is demonstrated as the range of 5-7 degreeC about the case of a flounder, if the low temperature acclimation temperature is made into about 6-12 degreeC in the case of Thailand. For other fish, it is only necessary to set a resting temperature and a low acclimation temperature suitable for the fish.

  That is, the upper limit survival temperature of the water temperature that can be tolerated by fish can be determined very accurately, and the individual difference is said to be within ± 0.2 ° C. for many fish species. On the other hand, it is difficult to accurately determine the minimum survival temperature of fish due to phenomena such as cold coma. Although it is possible to compare the temperature tolerance of various species and the difference between closely related species and subspecies, it is said that the low temperature lethal temperature is not necessarily similar even among species with similar high temperature lethal temperatures, Considering the lower limit value of the inhabitant water temperature and the lower limit water temperature of the fish that are currently known from past literature, etc., by conducting experimental studies, the resting temperature of each target fish The low temperature acclimation temperature may be selected individually and specifically in consideration of the stress applied to the fish body.

  Furthermore, the material, shape, structure, arrangement, and the like of the water tank and the transport container of the present invention are not specified to those described below by way of example in the embodiment of the present invention. That is, the technical idea of the present invention can be variously modified within the technical scope defined by the claims described in the claims.

(Temperature diagram)
In the hibernation induction method according to the embodiment of the present invention, as shown in the temperature diagram of FIG. 1, in a water tank maintained at a constant temperature at a resting breeding temperature T _A , the first time τ ₁ , the physiology of fish Suppressing metabolic function and voluntary movement, reducing the vitality by low-temperature warm-breeding and removing the stress on the fish body, and after the first time τ ₁ , Immediately move it into a water tank that is lower than _A and maintained at a constant temperature at a low temperature acclimation temperature T _B that further lowers the physiological metabolic function of the fish, and rapidly cool the fish, and keep the fish constant at the low temperature acclimation temperature T _B In a water bath maintained at a temperature of 2 for a second time τ ₂ , inducing the fish to a pseudo-hibernation state by further acclimatization and continuing acclimatization. The body temperature of fishes that are variable temperature animals (externally thermogenic animals) is about 0.5 to 1 ° C higher than the water temperature. If the water temperature changes, the body temperature also changes and the physiological metabolic function and spontaneous movement gradually decrease. . On the other hand, seawater has a large heat capacity and has 357 times the heat of air. Since the thermal conductivity of seawater is 1400 W / S · cm · ° C. compared to 57 W / S · cm · ° C. of air, seawater transfers a large amount of heat 24.5 times faster than air. Therefore, the whole body is in contact with the sea, especially for fish that breathe in seawater passing through Ella, a decrease in water temperature directly leads to a decrease in physiological metabolic function, and if the physiological metabolic function decreases, the energy to maintain the body decreases. Therefore, it becomes low in activity and is induced into a pseudo-hibernation state (cold coma).

Then, the anhydrous transport method according to the embodiment of the present invention is in addition to each stage of the hibernation induction method according to the above-described embodiment of the present invention, that is, it induces pseudo-hibernation (cold coma) and further acclimates. After the second time τ ₂ necessary for the stage has elapsed, the fish is further moved to a transport container having heat insulation (heat insulation), and the inside of the transport container is maintained at an oxygen concentration of 60% or more. and maintained at cold acclimation temperature T _B shown in the temperature diagram in Figure 1, by conveying the shipping container, the step of transporting a reduced fish oxygen consumption by the state of the pseudo-hibernation anhydrous environment Including.

As described above, since fish depend on gill respiration, it is assumed that in the absence of seawater, the gill valve cannot be supported by water, the effective gas exchange area is reduced, and oxygen is insufficient. Moreover, even if attention is paid to carbon dioxide (CO ₂ ) discharged by respiration, the discharge becomes difficult in a seawater-free environment, and in any case, it is fatal. However, the hibernation induction method according to the embodiment of the present invention, lowering the temperature of the surroundings to a cold acclimation temperature T _B, the body temperature of the fish is heterothermic also decreased similarly, the oxygen consumption of fish Physiological and metabolic functions such as the beginning are suppressed. Thus, by lowering the body temperature of the fish to a cold acclimation temperature T _B, when caused to lower the physiological metabolism of the fish by a low-temperature, under no sea water environment, that is, fish that gills to exchange oxygen and carbon dioxide even hard states, internal oxygen concentration of 60% or more of the environment of the shipping container, and by maintaining the environment of the cold acclimation temperature T _B, in the case of a transport with a transport period of 24 hours or more However, anhydrous transport is possible with a high resuscitation rate. Cold acclimation temperature T _B refers to the lower limit value or the like of the habitat temperature of fish that are now known by past literature, than the temperature showing the highest low metabolism amount at rest fish of interest, slightly higher What is necessary is just to reduce the stress given to the fish body of the fish selected as temperature.

According to hibernation induction method and anhydrous transportation method according to the embodiment of the present invention shown in the temperature diagram in FIG. 1, the cool-down stage (second stage) shown in FIG. 4, the water temperature T ₁ of the water tank containing the fish The step of gradually cooling (slow cooling) to the water temperature T ₁ is not necessary. Therefore, according to the hibernation induction method and the anhydrous transport method according to the embodiment of the present invention, it is necessary to use an expensive refrigerated water tank equipped with a temperature control device as compared with the conventional method based on the temperature diagram of FIG. And can induce fish into a pseudo-hibernation state at low cost.

Furthermore, according to the hibernation induction method and anhydrous transportation method according to the embodiment of the present invention, stress fish is subjected to induced pseudo hibernation state, the first time tau ₁ resting at rest farmed temperature T _A Because it is minimized by breeding, even if it is left in the air for 24 hours or more in an anhydrous environment using this pseudo-hibernation state, it is compared with the resuscitation rate by the conventional technique shown in Non-Patent Document 1 etc. Thus, the fish can survive with a high resuscitation rate (100% resuscitation rate is achieved after 24 hours, as shown in Examples 1-11 below for flounder).

(Flounder hibernation induction)
In the following, the hibernation induction method and the anhydrous transport method according to the embodiment of the present invention will be described in more detail using the apparatus configuration illustrated in FIGS. 2 and 3 as an example of flounder as a typical example of fish. From the past literature, it is assumed that the low temperature side water temperature of flatfish is 5 ° C, the optimal water temperature range for adult fish is 14-17 ° C, and the optimal water temperature range for adult fish is 8-23 ° C. 2, 2000, p. 1-315), considering the biological property values of these Japanese flounder, and further examining the experimental conditions that resulted in a long survival time in the following examples, in hibernation induction method according to the embodiment of the invention, at a temperature diagram shown in FIG. 1, 5 to 7 ° C. the cold acclimation temperature T _B of flounder, to determine the rest farmed temperature T _a of the flatfish 10 to 12 ° C. and Yes.

(A) First, the first aquarium 21 maintained at a constant temperature of resting culture temperature T _A = 10 to 12 ° C. shown in FIG. 2 (a), and the low temperature acclimation temperature T _B = shown in FIG. 2 (b) A second water tank 22 maintained at a constant temperature of 5 to 7 ° C. is prepared. Although the magnitude | size of the 1st water tank 21 and the 2nd water tank 22 is dependent also on the number of the flounder 1A, if it is about several, the size of 1m square is enough. The inner walls of the first water tank 21 and the second water tank 22 can be made of, for example, plastic such as polyvinyl chloride (PVC), titanium resistant to seawater, and the outer wall can be made of concrete. It is not limited. It is preferable to provide a heat blocking layer made of a heat insulating material between the inner wall and the outer wall. The first aquarium 21 contains normal seawater suitable for resting flounder 1A so as to have a constant salinity, and the second aquarium 22 is suitable for low-temperature acclimation of the flounder 1A. Normal seawater is stored so as to have a constant salinity. Although not shown, the first water tank 21 and the second water tank 22 are provided with a pump for sending air and a cooling device (seawater chiller) for cooling the seawater 31 and 32, and a constant dissolved oxygen concentration and a constant The water temperature is maintained. Alternatively, by omitting the cooling device (seawater chiller), digs the ice seawater 31 and 32, the respective temperatures of the sea water 31 and 32, controlled to be resting farmed temperature T _A and cold acclimation temperature T _B May be. The 1st water tank 21 and the 2nd water tank 22 are equipped with the lid | cover which can interrupt | block light, and can calm down the flounder 1A.

(B) The flounder 1A stored in the cage or net is moved one by one into the seawater 31 of the first aquarium 21 maintained at a constant temperature at the resting culture temperature T _A shown in FIG. 2 (a). . The flounder 1A is calmly cultivated at low water temperature by calming the swimming motion in the seawater with a constant salinity for the first time τ ₁ = 24 to 48 hours. As a result of low water temperature breeding in the absence of light, flounder 1A has its physiological metabolic function suppressed to a state close to low-temperature anesthesia, and its vitality is reduced, and stress on the flounder 1A fish body is removed. In FIG. 2 (a), only one flounder 1A is shown for simplification, but actually, a plurality of cages or nets are prepared, and one flounder 1A is provided for each cage or net. 1B, 1C,... Can be stored, and a plurality of flounder 1A, 1B, 1C,... Can be raised in the seawater 31 of the first aquarium 21 at a low water temperature. It is. The flounder 1A, which is a variable temperature animal housed in a cage or net, has its swimming activity subsided at the first time τ ₁ , at a resting culture temperature T _A , which is the lower limit temperature range of the inhabitant water temperature of the adult fish. Then, it is rested at a low water temperature and becomes half-sleeped, and the stress on the fish body is removed. Similarly, the other flounder 1B, 1C,..., Not shown in the figure, are put into a half-sleep state by being kept at low water temperature in the first time τ ₁ .

(C) After the elapse of the first time τ ₁ , the flatfish 1A housed in the basket or net is pulled up from the seawater 31 of the first water tank 21 by pulling up the basket or net, as shown in FIG. during cold acclimation temperature T seawater 32 of the second water tank 22 which is maintained at a constant temperature in _B, it is moved immediately quenching the flounder 1A. Similarly, other flounder 1B, 1C,..., Not shown, are immediately moved into the seawater 32 of the second water tank 22, and the other flounder 1B, 1C,. Each of the flounder 1A, 1B, 1C,... Is stored in a cage or net one by one and is in a sleeping state, so that each cage or net is lifted from the seawater 31 to be exposed to light, Even if it is moved from the first water tank 21 to the second water tank 22, this movement results in a substantial stay time in the air of the flounder 1A, 1B, 1C,. Because it can move in just a moment, the flounder 1A, 1B, 1C, etc. that have been slaughtered by being taken out into the air or irradiated with light will not wake up or rampage, but in the air A state in which the vitality is lowered is maintained.

(D) And, in the seawater 32 of the second tank 22 in which the flounder 1A is maintained at a constant temperature at the low temperature acclimation temperature T _B , the second time τ ₂ = 4 to 8 hours, resting in the absence of light. The flounder 1A, which is a variable temperature animal, is induced into pseudo-hibernation (cold coma). Similarly, other flounder 1B, 1C,..., Not shown, are also induced into a pseudo-hibernation state by being acclimated to rest for the second time τ ₂ . Although there are individual differences, flounder 1A, 1B, 1C,... Are usually induced to a pseudo-hibernation state in about 30 minutes.

(E) Then, after the elapse of the second time τ ₂ , the flounder 1A, 1B, 1C,... Induced in the pseudo-hibernation state is transported with heat insulation (insulation) as shown in FIG. It moves to the inside of the storage box 23. In FIG. 3, two flounder are illustrated, but in reality, a large number of flounder that are not shown are sequentially moved into the storage box 23 and stored. The storage box 23 is a heat insulating material such as foamed polystyrene or foamed polypropylene, and may be formed in a box shape such as a rectangular parallelepiped or a cylinder to achieve heat insulation (heat insulation). When a large number of flounder 1A, 1B, 1C,... Are stored inside the storage box 23, a shelf 231 made of a heat insulating material such as foamed plastic is provided inside the storage box 23 as shown in FIG. Also good. The shelves 231 are not limited to those shown in FIG. 3, and two or more shelves may be provided. After storing the flounder 1A, 1B, 1C,... In the storage box 23, a lid 232 for sealing the inside of the storage box 23 is attached to the upper end of the storage box 23 as shown in FIG. Construct containers (23, 231, 232). The lid 232 may also be made of a heat insulating material such as foamed plastic. In order to improve the sealing performance of the transport containers (23, 231, 232), a sealing film such as aluminum (film) may be further provided on the outer wall side of the storage box 23 and the upper surface of the lid 232, etc. The containers (23, 231, 232) may be housed in a sealed bag made of a material having a lower air permeability.

The storage box 23 is provided with a gas introduction pipe 44 and a gas exhaust pipe 46, the gas introduction pipe 44 is provided with a gas introduction control valve 43, and the gas exhaust pipe 46 is provided with a gas exhaust control valve 47. A flexible gas introduction pipe 42 is detachably connected to the gas introduction control valve 43 using a secret joint or the like, and the oxygen tank 24 is connected to the gas introduction pipe 42 via a pressure regulator 41. Oxygen (O ₂ ) gas whose pressure is adjusted by the pressure regulator 41 flows from the high-pressure oxygen tank 24 through the gas introduction pipe 42, and is transported through the gas introduction control valve 43 and the gas introduction pipe 44. Oxygen gas is injected into (23, 231, 232). When injecting oxygen gas, the gas exhaust control valve 47 is opened or close to the open state, and oxygen gas is injected into the transport container (23, 231, 232) from the gas introduction pipe 44 at a constant flow rate. . Although not shown, in order to inject oxygen gas into the transport container (23, 231, 232) at a constant flow rate, a flow meter is provided in a part of the path of the gas introduction pipe 42. . Although not shown, an oxygen sensor is provided on a part of the inside of the transport container (23, 231, 232) or on the exhaust side of the gas exhaust pipe 46, and the transport is performed while checking the value of the oxygen sensor. The oxygen gas is injected so that the oxygen gas concentration inside the container (23, 231, 232) is 60% or more. When the shelf 231 is provided inside the storage box 23, the vents 45a and 45b may be provided in the shelf 231. Instead of providing the vent holes 45a and 45b, the shelf 231 may be formed of a breathable plate.

When the inside of the transport container (23, 231, 232) reaches a predetermined oxygen concentration, the gas introduction control valve 43 and the gas exhaust control valve 47 are closed, and the interior of the transport container (23, 231, 232) is sealed. You can do it. In addition to the structure shown in FIG. 3, the storage box 23 is provided with two small holes for gas exchange. A nozzle similar to the gas introduction pipe 44 shown in FIG. When the gas is injected and the oxygen injection is completed, the two small holes may be closed with a sealing tape or the like. When the inside of the transport container (23, 231, 232) is sealed, the gas introduction pipe 42 for injecting oxygen gas is removed from the transport container (23, 231, 232), and then the oxygen concentration is 60% or more. been shipping container only (23,231,232) kept by transporting and maintain the cold acclimation temperature T _B, flounder 1A of pseudo hibernation, 1B, 1C, at ...... is anhydrous environment Transported. Although depending on the degree of sealing of the transport containers (23, 231, 232), the oxygen concentration may decrease by about 15 to 20% after 24 hours. It is sufficient to decide more.

  Of the following Examples 1 to 13, especially Example 10 shows that flounder, which is difficult to carry in anhydrous transport among fish, can be anhydrous for 52 hours. That is, according to the hibernation induction method and the anhydrous transport method according to the embodiment of the present invention, various fish including high-grade live fish such as flounder are in a fresh state even if a transport period of 2 days or more is required. It can be transported all over Japan or transported to various parts of the world by air transport, and it is possible to produce a remarkable effect that these pseudo-hibernating fish can be released into a ginger and awakened.

(Anhydrous survival conditions over 24 hours)
In the experiments using flounder according to the following Comparative Examples 1 to 15 and Examples 1 to 11, the flounder is anhydrous for 24 hours or more with substantially the same catching area, fishing method, and length so as not to widen individual differences. I searched for the conditions to survive. That is, the natural flounder fishing areas according to the following Comparative Examples 1 to 15 and Examples 1 to 11 are the Shimokita area and the Hachinohe area, and the flounder fishing methods are those for single fishing and stationary nets. These fishing methods are fishing methods that are less likely to cause damage to the flounder fish body, and that cause relatively little stress to the flounder fish body during fishing, and the flounder life time after catching is long, and are suitable for live fish shipment. The body length of the flounder according to the following Comparative Examples 1 to 15 and Examples 1 to 11 is about 40 to 50 cm. These flounder are 1 to 1.5 kg in terms of body weight, but the experiment was focused on flounder, which is considered the most delicious and has a high unit price. That is, flounder according to the following Comparative Examples 1 to 15 and Examples 1 to 11 designates body lengths that are most likely to concentrate the shipping ratio. In addition, even in Japanese flounder with different body lengths, no significant difference is observed under the temperature and time conditions specified in Examples 1 to 11 within the range of body lengths of 40 cm to 60 cm used for live fish transportation, and both can survive anhydrous. I know. Natural flounder less than 35 cm in length is not caught.

  In the following Comparative Examples 1 to 15 and Examples 1 to 11, the number of specimens of flounder in each test section is 4 each, and an electrocardiograph (a high-sensitivity amplifier for living body) is attached to one flounder, Anhydrous survival time was measured by measuring heart rate while keeping anhydrous. The remaining three flounder were returned to seawater at 15 ° C. 24 hours after the start of the anhydrous survival test, and a resuscitation experiment was conducted.

表１に示すように、安静畜養温度Ｔ_A＝２０℃の比較例１、安静畜養温度Ｔ_A＝１５℃の比較例２、安静畜養温度Ｔ_A＝５℃の比較例３の場合、無水生存時間は、それぞれ６時間、１３時間、０時間であり、いずれも２４時間生存できていないので、２４時間後の蘇生実験では３尾とも蘇生しないという結果であった。一方、安静畜養温度Ｔ_A＝１０℃の実施例１〜４ではいずれも、２４時間後の蘇生実験では３尾とも蘇生して蘇生率１００％であることが分かる。実施例１及び２の安静畜養に用いる第１の時間τ₁＝２４時間であるが、実施例３の第１の時間τ₁＝４８時間、及び実施例４の第１の時間τ₁＝９６時間でも、２４時間後の蘇生実験で３尾とも蘇生しているので、安静畜養に用いる第１の時間τ₁＝２４時間以上であれば良好な結果が得られることが分かるが、産業的な応用面を考慮すると、現場の品物の回転スピードや、ヒラメの身痩せ防止を考え、時間はなるべく短い方がよいので、安静畜養に用いる第１の時間τ₁＝２４時間が最適であると判断できる。また、表１から安静畜養温度Ｔ_A＝１０℃が、２４時間後の蘇生率１００％の実現に最適であることが分かる。 (A) Identification of holding temperature and time during resting

As shown in Table 1, in the case of Comparative Example 1 where the resting temperature T _A = 20 ° C, Comparative Example 2 where the resting temperature T _A = 15 ° C, and Comparative Example 3 where the resting temperature T _A = 5 ° C, anhydrous survival The time was 6 hours, 13 hours, and 0 hours, respectively, and none of them was able to survive for 24 hours. Therefore, in the resuscitation experiment after 24 hours, it was the result that none of the 3 fishes were resuscitated. On the other hand, in Examples 1 to 4 where the resting temperature T _{A is} 10 ° C., it is found that in the resuscitation experiment after 24 hours, all three animals were revived and the resuscitation rate was 100%. The first time τ ₁ = 24 hours used for the resting of Examples 1 and 2, but the first time τ ₁ = 48 hours of Example 3 and the first time τ ₁ = 96 of Example 4 In terms of time, all three fish have been revived in the resuscitation experiment 24 hours later, so it can be seen that good results can be obtained if the first time τ ₁ = 24 hours or more used for resting livestock is Considering the application aspect, considering the rotation speed of items on the site and preventing slimming of flounder, the time should be as short as possible, so the first time τ ₁ = 24 hours used for resting is determined to be optimal. it can. Moreover, it can be seen from Table 1 that the resting culture temperature T _A = 10 ° C. is optimal for realizing a resuscitation rate of 100% after 24 hours.

表２の比較例５に示すように、冷却速度０．３℃／時では、無水生存時間が２６時間で、２４時間後の蘇生実験では、２尾蘇生、１尾死亡という結果であった（蘇生率６７％）。一方、比較例６に示すように、冷却速度２℃／時では、無水生存時間が２７時間で、２４時間後の蘇生実験では、３尾蘇生という結果であり、実施例５に示すように、徐冷せず、ステップ状に５℃の急冷した場合も無水生存時間が２７時間で、２４時間後の蘇生実験では、３尾蘇生（蘇生率１００％）という結果が得られた。即ち、図４に示すクールダウン段階での冷却速度は、２℃／時よりも急激に冷却すれば、冷却速度は、無水生存時間にほとんど効果を与えないことが分かる。既に、背景技術の欄で説明したとおり、２℃／時のように徐冷をする場合、冷却速度をコントロールする技術あるいは専用の機械が必要になる。なるべく簡便な方法で冬眠させることが出来、しかも２４時間後の蘇生率１００％を実現するという点から、実施例５に示すように、徐冷せず、ステップ状に５℃の急冷をするのが好ましいと判断できる。比較例５に示すように、０．３℃／時間で５℃の徐冷をするとすれば１６．７時間のクールダウン時間とそのための電気代等が必要となるので、ステップ状の急冷を用いる、本発明の実施の形態に係る冬眠誘導方法の顕著な効果が明らかである。 (B) Identification of cool-down speed

As shown in Comparative Example 5 of Table 2, when the cooling rate was 0.3 ° C./hour, the anhydrous survival time was 26 hours, and the resuscitation experiment after 24 hours resulted in 2 resuscitation and 1 death ( Resuscitation rate 67%). On the other hand, as shown in Comparative Example 6, at a cooling rate of 2 ° C./hour, the anhydrous survival time was 27 hours, and in the resuscitation experiment after 24 hours, the result was 3 tail resuscitation. Even if it was not gradually cooled and rapidly cooled at 5 ° C in steps, the anhydrous survival time was 27 hours, and in the resuscitation experiment after 24 hours, a result of 3 tail resuscitation (resuscitation rate 100%) was obtained. That is, it can be seen that the cooling rate at the cool-down stage shown in FIG. 4 has little effect on the anhydrous survival time if it is cooled more rapidly than 2 ° C./hour. As already described in the Background Art section, when slow cooling is performed at 2 ° C./hour, a technology for controlling the cooling rate or a dedicated machine is required. From the point of being able to hibernate by the simplest possible method and achieving a resuscitation rate of 100% after 24 hours, as shown in Example 5, perform rapid cooling at 5 ° C. in a stepwise manner without slow cooling. Can be determined to be preferable. As shown in Comparative Example 5, if a slow cooling of 5 ° C. is performed at 0.3 ° C./hour, a 16.7 hour cool-down time and an electric bill for that are required, so stepped rapid cooling is used. The remarkable effect of the hibernation induction method according to the embodiment of the present invention is clear.

表３に示すように、低温馴化温度Ｔ_B＝３℃の比較例７、低温馴化温度Ｔ_B＝１．５℃の比較例８の場合、無水生存時間は、それぞれ、１７時間、１４時間であり、いずれも２４時間生存できていないので、２４時間後の蘇生実験では３尾とも蘇生しないという結果であった。また、 低温馴化温度Ｔ_B＝５℃の場合であっても、低温馴化に用いる経過時間（第２の時間）τ₂＝２時間の比較例９、経過時間（第２の時間）τ₂＝２４時間の比較例１０、経過時間（第２の時間）τ₂＝７２時間の比較例１１の場合、無水生存時間は、それぞれ、２２時間、２１時間、１７時間であり、いずれも２４時間生存できていないので、２４時間後の蘇生実験では３尾とも蘇生しないという結果であった。一方、低温馴化温度Ｔ_B＝５℃で、経過時間（第２の時間）τ₂＝４時間の実施例６、７では、無水生存時間は、いずれも３０時間であり、２４時間後の蘇生実験ではいずれも３尾とも蘇生という蘇生率１００％の結果であった。実施例６、７の結果から、低温馴化温度Ｔ_B＝５℃で、経過時間（第２の時間）τ₂＝４時間が、２４時間後の蘇生率１００％を実現する本発明の実施の形態に係る冬眠誘導方法に最適であると判断できる。 (C) Identification of holding temperature and time during low temperature acclimation

As shown in Table 3, in the case of Comparative Example 7 where the low temperature acclimation temperature T _B = 3 ° C. and the Comparative Example 8 where the low temperature acclimation temperature T _B = 1.5 ° C., the anhydrous survival times were 17 hours and 14 hours, respectively. Yes, none of them survived for 24 hours, and in the resuscitation experiment after 24 hours, none of them revived. Further, even in the case of the low temperature acclimation temperature T _B = 5 ° C., the elapsed time (second time) τ ₂ = 2 hours used for the low temperature acclimation, the comparative example 9 of elapsed time (second time) τ ₂ = In the case of Comparative Example 10 with 24 hours and Comparative Example 11 with elapsed time (second time) τ ₂ = 72 hours, the anhydrous survival times were 22 hours, 21 hours, and 17 hours, respectively, and all survived for 24 hours. Since it was not completed, the result of the resuscitation experiment after 24 hours was that all three were not resuscitated. On the other hand, in Examples 6 and 7 where the low temperature acclimation temperature T _B = 5 ° C. and the elapsed time (second time) τ ₂ = 4 hours, the anhydrous survival time was 30 hours, and resuscitation after 24 hours. In the experiment, all three were resuscitated with a resuscitation rate of 100%. From the results of Examples 6 and 7, the low temperature acclimation temperature T _B = 5 ° C., the elapsed time (second time) τ ₂ = 4 hours, and realizing the resuscitation rate after 24 hours of 100%. It can be judged that it is optimal for the hibernation induction method according to the form.

表４に示すように、無水保持温度＝低温馴化温度Ｔ_B＝１．５℃の比較例１２、無水保持温度＝低温馴化温度Ｔ_B＝３℃の比較例１３、無水保持温度＝低温馴化温度Ｔ_B＝８℃の比較例１４の場合、無水生存時間は、それぞれ、１４時間、１７時間、２時間であり、いずれも２４時間生存できていないので、２４時間後の蘇生実験では３尾とも蘇生しないという結果であった。一方、無水保持温度＝低温馴化温度Ｔ_B＝５℃の実施例８では、無水生存時間が３０時間で、２４時間後の蘇生実験では３尾とも蘇生し、蘇生率１００％であることが分かる。表４から無水保持温度＝低温馴化温度Ｔ_B＝５℃が、２４時間後の蘇生率１００％を実現する本発明の実施の形態に係る冬眠誘導方法に最適であることが分かる。 (D) Identification of holding temperature when left in the air

As shown in Table 4, anhydrous holding temperature = low-temperature acclimation temperature T _B = 1.5 ° C. Comparative Example 12, anhydrous holding temperature = low-temperature acclimation temperature T _B = 3 ° C. Comparative Example 13, anhydrous holding temperature = low-temperature acclimation temperature In the case of Comparative Example 14 where T _B = 8 ° C., the anhydrous survival times were 14 hours, 17 hours, and 2 hours, respectively, and none of them survived for 24 hours. The result was not to be resuscitated. On the other hand, in Example 8 where the anhydrous retention temperature = low temperature acclimation temperature T _B = 5 ° C., the anhydrous survival time is 30 hours, and in the resuscitation experiment after 24 hours, all three animals are revived and the resuscitation rate is 100%. . From Table 4, it can be seen that anhydrous holding temperature = low temperature acclimation temperature T _B = 5 ° C. is optimal for the hibernation induction method according to the embodiment of the present invention that realizes a resuscitation rate of 24% after 24 hours.

表５に示すように、無水保持温度＝低温馴化温度Ｔ_B＝５℃に統一した実験において、空中放置時の酸素濃度２０％の比較例１５の場合、無水生存時間は２２時間であり、２４時間後の蘇生実験では３尾とも蘇生しないという結果であった。一方、空中放置時の酸素濃度４０％の実施例９、空中放置時の酸素濃度６０％の実施例１０、空中放置時の酸素濃度８０％の実施例１１では、無水生存時間は、それぞれ、４８時間、５２時間、５０時間であり、２４時間後の蘇生実験では３尾とも蘇生し、蘇生率１００％であることが分かる。実施例９〜１０の結果から、酸素濃度は６０％が最も好ましく、５２時間の無水生存時間が実現できており、２日以上の無水生存のためには、無水環境での空中放置時の酸素濃度を６０％以上とすることが好ましいと判断できる。
以上において説明したとおり、本発明の実施の形態に係る冬眠誘導方法によれば、酸素濃度を６０％以上とすることにより、無水環境下で、約２日間（最大５２時間）のヒラメの生存が確保できたという顕著な効果が理解できる。 (E) Identification of oxygen concentration when left in the air

As shown in Table 5, in the experiment in which the anhydrous retention temperature = the low temperature acclimation temperature T _B = 5 ° C., in the case of Comparative Example 15 with an oxygen concentration of 20% when left in the air, the anhydrous survival time is 22 hours, 24 In the resuscitation experiment after time, it was the result that all three were not resuscitated. On the other hand, in Example 9 with an oxygen concentration of 40% when left in the air, Example 10 with an oxygen concentration of 60% when left in the air, and Example 11 with an oxygen concentration of 80% when left in the air, the anhydrous survival time was 48 respectively. It is time, 52 hours, and 50 hours, and in the resuscitation experiment after 24 hours, it can be seen that all three animals were revived and the resuscitation rate was 100%. From the results of Examples 9 to 10, the oxygen concentration is most preferably 60%, and an anhydrous survival time of 52 hours can be realized. For an anhydrous survival of 2 days or more, oxygen when left in the air in an anhydrous environment It can be determined that the concentration is preferably 60% or more.
As described above, according to the hibernation induction method according to the embodiment of the present invention, by setting the oxygen concentration to 60% or more, flounder can survive for about 2 days (up to 52 hours) in an anhydrous environment. You can understand the remarkable effect that it was secured.

(Stress on flounder fish)
In the experiment relating to the measurement of the lactic acid level of the Japanese flounder according to Comparative Example 16 and Examples 12 and 13 below, as with the Japanese flounder according to Comparative Examples 1 to 15 and Examples 1 to 11 described above, The fishing areas are the Shimokita and Hachinohe areas, and the fishing method of the specimen is that of single fishing and stationary net, and the body length of the specimen is about 42 to 46 cm and the weight is about 1.06 to 1.34 kg. In the following Comparative Example 16 and Examples 12 and 13, the number of flounder samples in each test section was five, and the average value was measured and compared with each other. Lactic acid levels were measured by high performance liquid chromatography after deproteinization of flounder samples with perchloric acid.

表６に示すとおり、即殺直後の乳酸値は、比較例１６、実施例１２及び１３のいずれの試験区においても約２００ｍｇ／１００ｇ程度の値であり有意水準５％で、その数値に有意差は認められない。また、即殺後２日経過した後は、比較例１６、実施例１２及び１３のいずれの試験区においても約８００ｍｇ／１００ｇ程度の値に増加し、即殺後３日経過した後は、比較例１６、実施例１２及び１３のいずれの試験区においても約７２０ｍｇ／１００ｇ程度の値に減少に転じている。 表６に示す結果から、各試験区における乳酸値に有意な差が認められないので、図１に示す温度ダイアグラムに沿った本発明の実施の形態に係る冬眠誘導方法により、疲労物質としての乳酸値の増加は、標準サンプルとしての普通に泳いでいるヒラメに比して増加していないと結論できる。 In Table 6 below, Comparative Example 16 is a standard sample, which is not induced by the pseudo-hibernation state without any low-temperature treatment of the temperature diagram shown in FIG. It is. That is, in Comparative Example 16, the average value of the lactic acid value was determined by laying down (immediately killing) flounder serving as five standard samples swimming normally in an aquarium. Example 12 is an average value of 5 flounder slaughtered immediately during anhydrous hibernation (after 24 hours). Example 12 is the average value of 5 flounder that were put into seawater after 24 hours from the start of anhydrous hibernation and killed immediately after resuscitation. During the resuscitation from the anhydrous hibernation state, there was a question that the fish body was stressed and adversely affected the meat components. Therefore, Example 12 related to Japanese flounder before resuscitation and Example 13 related to Japanese flounder after resuscitation Each component of was compared. Moreover, since the increase in the lactic acid level immediately after the killing is remarkable in the fish in which stress and fatigue applied to the fish body are accumulated, as shown in Table 6, all of the comparative examples 16 and Examples 12 and 13 until 3 days after the killing. Following the change in the lactic acid level, the effect of the increase in the lactic acid level immediately after killing was excluded.

As shown in Table 6, the lactic acid level immediately after killing was about 200 mg / 100 g in all the test groups of Comparative Example 16, Examples 12 and 13, and the significance level was 5%. It is not allowed. In addition, after 2 days have passed since the instant killing, it increased to a value of about 800 mg / 100 g in any of the test groups of Comparative Example 16, Examples 12 and 13, and after 3 days after the instant killing, In all the test sections of Example 16 and Examples 12 and 13, the value started to decrease to a value of about 720 mg / 100 g. From the results shown in Table 6, since there is no significant difference in the lactic acid value in each test section, lactic acid as a fatigue substance was obtained by the hibernation induction method according to the embodiment of the present invention along the temperature diagram shown in FIG. It can be concluded that the increase in value is not increased compared to the normal swimming flounder as a standard sample.

As described in the above, according to the hibernation induction method according to the embodiment of the present invention, than the temperature that indicates the metabolism of most low resting flounder, to cold acclimation temperature T _B is slightly higher temperatures, the pseudo By maintaining the body temperature of the hibernating flounder, it is possible to prevent an increase in the lactic acid level from being observed in the flounder after the lapse of the pseudo-hibernation state for 24 hours compared to the flounder that is not induced in the pseudo-hibernation state. Therefore, according to the hibernation induction method according to the embodiment of the present invention, since there is no accumulation of stress and fatigue on the fish body, the resuscitation rate of flounder after 24 hours of pseudo hibernation is high, and 24 hours of pseudo hibernation. Depending on the state, it is possible to achieve a remarkable effect that the quality of the flounder as a live fish does not deteriorate, such as leaning.

(Other embodiments)
Although the embodiments of the present invention have been described by the above specific examples, it should not be understood that the descriptions and drawings constituting a part of this disclosure limit the present invention. From this disclosure, various alternative embodiments, examples and operational techniques will be apparent to those skilled in the art.

  In the description of the embodiment of the present invention described above, the outline of the flounder hibernation induction method and the flounder anhydrous transport method using this hibernation induction method is merely illustrative. . Therefore, it will be easily understood from the above description that the hibernation induction method and the anhydrous transport method of the present invention can be applied to various fishes other than flounder. As described above, the present invention naturally includes various embodiments that are not described herein, modifications thereof, and the like. Therefore, the technical scope of the present invention is defined only by the invention specifying matters according to the scope of claims reasonable from the above description.

  According to the hibernation induction method and the anhydrous transport method according to the embodiment of the present invention, even a flounder, which is difficult to transport anhydrous, among fish, can be anhydrous for 52 hours. Therefore, according to the hibernation induction method and the anhydrous transport method according to the embodiment of the present invention, various fish including high-grade live fish such as flounder, even in the case of long-distance transport that requires a transport period of 2 days or more, Since it can be transported to the whole country in Japan or transported to various parts of the world by air transportation, the present invention can be used in industries such as fisheries industry, fishery cooperatives, fisheries wholesale trade, distribution industry and transportation industry. Furthermore, the present invention can also be used in industries such as service industries that provide fresh and delicious fish dishes such as restaurants and restaurants that cook and provide these anhydrous transported fish.

1A, 1B, 1C, ... Flatfish 21 ... First water tank 22 ... Second water tank 23 ... Storage box 24 ... Oxygen tank 31 ... Sea water 32 ... Sea water 41 ... Pressure regulator 42 ... Gas introduction pipe 43 ... Gas introduction control valve 44 ... Gas introduction pipes 45a, 45b ... Vent holes 46 ... Gas exhaust pipe 47 ... Gas exhaust control valve

Claims (2)

In a water tank maintained at a rest-breeding temperature, raising the fish at rest for a first time;
After the passage of the first time, rapidly moving the fish by moving it into a water tank maintained at a low acclimation temperature lower than the resting temperature;
Inducing the fish into a pseudo-hibernation state by allowing the fish to rest in a water bath maintained at the low temperature acclimation temperature for a second time, and further acclimating;
A hibernation induction method comprising:
In a water tank maintained at a rest-breeding temperature, raising the fish at rest for a first time;
After the passage of the first time, rapidly moving the fish by moving it into a water tank maintained at a low acclimation temperature lower than the resting temperature;
Inducing the fish into a pseudo-hibernation state by allowing the fish to rest in a water bath maintained at the low temperature acclimation temperature for a second time, and further acclimating;
After the elapse of the second time, the fish is moved to a transport container, and the transport container is transported while maintaining the inside of the transport container at an oxygen concentration of 60% or more and the low temperature acclimation temperature. Transporting the fish in the pseudo-hibernation state in an anhydrous environment;
An anhydrous transport method comprising:

Images