Test fish feeding device

Abstract

To improve the workability of inserting test fish into the test fish holding section while reducing the burden on the test fish and enabling the test fish to be inserted in a stable posture relative to the test fish holding section in a test fish inserting device for inserting test fish together with water into a specified test fish holding section. [Solution] It is composed of a bottomed, cylindrical container body 51 capable of containing a test fish F together with water W inside, and when a container tilting and pouring operation is performed in which the container body 51 is tilted and the contents of the container body 51 are poured into a designated test fish holding section 12, the test fish F contained inside the container body 51 is released together with the water W from a designated release edge 59 located on the upper edge of the container body 51 and poured into the test fish holding section 12, and is equipped with a test fish release promotion section D which promotes the release of the test fish F before the release of the water W from inside the container body 51 is completed when the container tilting and pouring operation is performed.

Description

[Technical field]

[0001] The present invention relates to a test fish introducing device for introducing test fish together with water into a specified test fish holding section. [Background technology]

[0002] In recent years, zebrafish have been attracting a great deal of attention as experimental animals. In animal experiments using test fish such as zebrafish, for example, when holding the test fish during a specific treatment such as oral administration, it is important to hold the test fish as gently as possible while minimizing stress and damage to the test fish, that is, without damaging the body surface or causing burns. Therefore, a test fish holding device has been proposed that can minimize stress and damage to the test fish and securely hold the test fish in a predetermined posture after it is placed into a holding groove that serves as a test fish holding section (see, for example, Patent Document 1). Furthermore, Patent Document 1 describes a test fish introduction device for introducing test fish together with water into a predetermined test fish holding section. The test fish introduction device described in Patent Document 1 includes an inclined pipe member for guiding the test fish together with water to a holding groove formed as a test fish holding section in a flexible holder. That is, the inclined pipe member is inclined with respect to the horizontal, and the upper end portion is configured as an introduction port that opens upward, and the lower end portion is configured as an outlet that opens downward toward the inside of the holding groove. When the test fish is introduced into the introduction port of the inclined pipe member together with water, the introduced test fish is guided to the outlet by the water flow formed inside the inclined pipe member, and is released from the outlet together with water into the inside of the holding groove. In this test fish introduction device, the posture of the test fish can be moderately stabilized by passing the inside of the inclined pipe member on the water flow, and the test fish can be released into the holding groove together with water while maintaining a stable posture, and can be held inside the holding groove. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2022 / 210397 Summary of the Invention [Problem to be solved by the invention]

[0004] The test fish introduction device described in the above-mentioned Patent Document 1 requires work to lift the test fish to the height of the introduction port located at a relatively high position, and work to temporarily move the inclined pipe member that interferes when removing the holder with the test fish introduced into the holding groove from above the holder. Such work is so slight that it does not cause a problem when orally administering to a small number of test fish, but when orally administering to a large number of test fish, it is desirable to reduce it in order to improve work efficiency. In light of this situation, the main object of the present invention is to provide a technology in a test fish introducing device for introducing test fish together with water into a designated test fish holding section, which reduces the burden on the test fish and enables the test fish to be introduced into the test fish holding section in a stable posture, while improving the workability of introducing the test fish into the test fish holding section. [Means for solving the problem]

[0005] The first characteristic configuration of the present invention is a test fish introduction device for introducing a test fish together with water into a predetermined test fish holding section, It is composed of a cylindrical container body with a bottom that can hold the test fish together with water inside. A container tilting and pouring operation is performed in which the container body is tilted and the contents of the container body are poured into a specified test fish holding section, whereby the test fish contained inside the container body are released together with water from a specified release edge located on the upper edge of the container body and poured into the test fish holding section, The container is provided with a test fish release promotion section that promotes the release of test fish before the release of water from inside the container body is completed when the container tilting and inserting operation is performed.

[0006] According to this configuration, by providing the test fish release promotion part, when the container tilting operation is performed, the release of the test fish contained in the container body from the release edge is promoted before the water contained in the container body is completely released from the release edge. This makes it easier to insert the test fish into the test fish holding part, improving workability. Furthermore, even after the test fish is inserted into the test fish holding part, water can be continuously poured in for a certain period of time. This keeps the test fish held in the test fish holding part immersed in water for at least a certain period of time, calming the test fish without causing any violence, and reducing stress and damage to the test fish. Furthermore, when water can be retained inside the test fish holding part, a water flow can be formed along the extension direction of the test fish holding part while keeping the test fish held inside the test fish holding part moderately immersed in water to a depth deep enough to allow the test fish to exhibit swimming ability. Furthermore, since fish generally have the habit of swimming against the current of water, the posture of the test fish placed inside the test fish holding section can be stabilized in a posture against the current of water. Therefore, the present invention provides a technology for a test fish introducing device for introducing test fish together with water into a designated test fish holding section, which reduces the burden on the test fish and enables the test fish to be introduced into the test fish holding section in a stable posture, while improving the workability of introducing the test fish into the test fish holding section.

[0007] The second characteristic configuration of the present invention is that a groove-shaped test fish release promotion groove portion is formed on the inner wall surface side of the container body, extending downward from the release edge portion to a length equal to or greater than the entire length of the test fish, The test fish release promotion groove portion functions as the test fish release promotion portion by guiding the test fish toward the release edge portion and forming a water flow toward the release edge portion when the container tilting and dropping operation is performed.

[0008] According to this configuration, when performing the container tilting and inserting operation, when the container body starts to be tilted, the test fish housed inside the container body enters the test fish release promoting groove, so that the posture of the test fish can be maintained along the test fish release promoting groove. Then, when the tilt angle of the container body (the angle of the axis of the container body relative to the vertical direction) is increased and water is started to be released from the release edge, a water flow toward the release edge is formed in the test fish release promoting groove while maintaining a water depth sufficient for the test fish to demonstrate their swimming ability, so that the test fish can be stabilized in a posture against the water flow in the test fish release promoting groove. Furthermore, when the tilt angle of the container body is increased, the water flow in the test fish release promoting groove becomes stronger, so that the test fish can be released from the tail fin while maintaining a stable posture before the completion of the release of water from inside the container body, and further, water can be continuously introduced more satisfactorily even after the test fish is introduced into the test fish holding part.

[0009] The third characteristic configuration of the present invention is that, on the inner wall surface side of the container body, the bottom of the test fish release promotion groove portion is formed so as to slope outwardly as it goes upward further than the portions on both sides of the test fish release promotion groove portion.

[0010] According to this configuration, when performing the container tilting insertion operation, the bottom of the test fish release promotion groove becomes inclined toward the release edge before the two sides of the test fish release promotion groove are sandwiched. As a result, before the water contained inside the container body is completely released from the release edge (the release of water from the inside of the container body is completed), the test fish contained inside the container body is released from the release edge along the bottom of the test fish release promotion groove that becomes inclined before the two sides of the test fish release promotion groove are sandwiched while being held in the test fish release promotion groove, so that the release of the test fish from the release edge is promoted before the release of water from the inside of the container body is completed. And, even after the test fish is put into the test fish holding part, water can be continuously put in even better.

[0011] The fourth characteristic configuration of the present invention is that a partition body is provided inside the container body in a position inclined upward toward the discharge edge, dividing the inside of the container body into an upper test fish storage space in which the test fish are stored and which is connected to the discharge edge, and a lower water storage space in which only water is stored and which is connected to the discharge edge, without storing the test fish; The partition body functions as the test fish release promotion section by assuming a release inclined state in which it descends toward the release edge before the inner wall surface of the container body when the container tilting insertion operation is performed.

[0012] According to this configuration, when performing the container tilting input operation, the partition body provided inside the container body in a posture inclined upward toward the discharge edge becomes in a discharge tilted state, descending toward the discharge edge side, before the inner wall surface of the container body. As a result, before the water contained in the water containing space below the partition body inside the container body is completely discharged (the discharge of water from the inside of the container body is completed), the test fish contained in the test fish containing space above the partition body inside the container body is discharged from the discharge edge along the partition body that becomes in a discharge tilted state before the inner wall surface of the container body, and the discharge of the test fish from the discharge edge before the discharge of water from the inside of the container body is completed is promoted. Then, even after the test fish is input into the test fish holding part, water can be continuously input more smoothly.

[0013] A fifth characteristic configuration of the present invention is a partition swing support part that supports the partition so that it can swing between a discharge edge closing position in which the communication part from the water storage space to the discharge edge is closed and a discharge edge opening position in which the communication part from the water storage space to the discharge edge is opened, When the container tilting and pouring operation is performed, before the test fish contained in the test fish holding space is released, the partition body is in the release edge closed position, thereby suppressing the release of water contained in the water holding space from the release edge, and after the test fish contained in the test fish holding space is released, the partition body is in the release edge open position, thereby allowing the release of water contained in the water holding space from the release edge.

[0014] According to this configuration, when performing the container tilting and pouring operation, before the test fish contained in the test fish storage space is released, the partition body is in a release edge closing position that closes the communication part from the water storage space to the release edge. Then, the release of water contained in the water storage space from the release edge is suppressed, so that only the test fish and water contained in the test fish storage space are released from the release edge, and a relatively large amount of water can be stored in the water storage space without being released. Then, after the test fish contained in the test fish storage space is released, the partition body is in a release edge opening position that opens the communication part from the water storage space to the release edge. Then, a relatively large amount of water contained in the water storage space is allowed to be released from the release edge, so a large amount of water can be continuously poured into the test fish holding part holding the test fish for a relatively long time. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 is a perspective view showing a disassembled state of a test fish holding device. [Diagram 2] Front view of the state shown in Figure 1 [Diagram 3] Left side view of the state shown in Figure 1 [Figure 4] FIG. 2 is a front cross-sectional view showing the state immediately after the test fish is placed in the holding groove in the test fish holding device with the holding tool installed. [Diagram 5] 5 is a left side cross-sectional view of the state shown in FIG. 4. [Figure 6] FIG. 2 is a front cross-sectional view showing the test fish holding device with the holding device installed and the insertion tool in the discharge chute removal position. [Figure 7] FIG. 13 is a front cross-sectional view showing the state in which the holder holding the test fish inside the holding groove is removed from the holder installation case. [Figure 8] FIG. 1 shows the state of oral administration to test fish held in a holder. [Figure 9] Front view of the test fish throwing device of the first embodiment [Figure 10] Left side view of the test fish throwing device of the first embodiment [Figure 11] Plan view of the test fish throwing device of the first embodiment [Figure 12] FIG. 1 is a front cross-sectional view showing a first step of a test fish introduction method according to a first embodiment; [Figure 13] FIG. 1 is a front cross-sectional view showing a second step of the test fish introduction method in the first embodiment; [Figure 14] FIG. 11 is a front cross-sectional view showing a third step of the test fish introduction method in the first embodiment. [Figure 15] FIG. 11 is a front cross-sectional view showing a fourth step of the test fish introduction method in the first embodiment. [Figure 16] Front view of the test fish throwing device of the second embodiment [Figure 17] Left side view of the test fish throwing device of the second embodiment [Figure 18] Plan view of the test fish throwing device of the second embodiment [Figure 19] 2 is a cross-sectional view of a test fish throwing device according to a second embodiment of the present invention; [Figure 20] Front view of the test fish throwing device of the third embodiment [Figure 21] Left side view of the test fish throwing device of the third embodiment [Figure 22] Plan view of the test fish throwing device of the third embodiment [Diagram 23] FIG. 13 is a front cross-sectional view showing the state of the first step of the test fish introduction method in the third embodiment. [Figure 24] FIG. 13 is a front cross-sectional view showing the second step of the test fish introduction method in the third embodiment. [Diagram 25] FIG. 13 is a front cross-sectional view showing the third step of the test fish introduction method in the third embodiment. [Figure 26] FIG. 13 is a front cross-sectional view showing the fourth step of the test fish introduction method in the third embodiment. [Figure 27] Front view of the test fish throwing device of the fourth embodiment [Figure 28] Left side view of the test fish throwing device of the fourth embodiment [Figure 29] Plan view of the test fish throwing device of the fourth embodiment [Diagram 30] FIG. 13 is a front cross-sectional view showing the state of the first step of the test fish introduction method in the fourth embodiment. [Diagram 31] FIG. 13 is a front cross-sectional view showing the second step of the test fish introduction method in the fourth embodiment. [Diagram 32] FIG. 13 is a front cross-sectional view showing the third step of the test fish introduction method in the fourth embodiment. [Diagram 33] FIG. 13 is a front cross-sectional view showing the fourth step of the test fish introduction method in the fourth embodiment. [Diagram 34] Front view of the test fish throwing device of the fifth embodiment [Diagram 35] Left side view of the test fish throwing device of the fifth embodiment [Diagram 36] Plan view of the test fish throwing device of the fifth embodiment [Figure 37] FIG. 13 is a front cross-sectional view showing the state of the first step of the test fish introduction method in the fifth embodiment. [Figure 38] FIG. 13 is a front cross-sectional view showing the second step of the test fish introduction method in the fifth embodiment. [Figure 39] FIG. 13 is a front cross-sectional view showing the third step of the test fish introduction method in the fifth embodiment. [Diagram 40] FIG. 13 is a front cross-sectional view showing the fourth step of the test fish introduction method in the fifth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] An embodiment of a test fish throwing device according to the present invention will be described with reference to the drawings. As shown in Figures 4 and 5, the test fish throwing device (hereinafter referred to as the "test fish throwing device") 5 of this embodiment, details of which will be described later, is a device for throwing a test fish F together with water W into a specified test fish holding section. The test fish holding section is a holding groove 12 provided in a specified test fish holding device. First, the details of the test fish holding device will be described with reference to the drawings.

[0017] [Test fish holding device] The test fish holding device, as shown in Figure 8, is a facility for holding test fish F for various live observations or live experiments, and is configured to be able to efficiently perform specified procedures such as direct oral administration to the test fish F while reducing the burden on the relatively small test fish F that are the subject of observation or experiments.

[0018] As shown in Figs. 4, 5, 6 and 7, the test fish holding device is composed of a holder 10, a holder installation case 30, and an insertion tool 40, etc. Although details will be described later, the holder 10 is made of a flexible material, and a holding groove 12 that is open on the upper surface 10a side and extends along the front-rear direction X is formed as a test fish holding portion. On the other hand, the holder installation case 30 is configured as a container-like holder installation portion that houses the holder 10 inside. In the holder installation state in which the holder 10 is installed in the holder installation case 30 (for example, the state shown in Figures 4 and 5), the holding groove 12 is configured to hold inside a test fish F that is dropped in together with water W from the groove upper opening 12a, which is the opening on the upper surface 10a side. In this embodiment, the test fish F is assumed to be a zebrafish, but any small fish used in live experiments can be used as the test fish F, such as a fathead minnow, ricefish, or guppy.

[0019] The holder 10 is made of a material that is flexible, permeable, and has water retention, such as a sponge. In this embodiment, the holder 10 is made of sponge as a whole, but it may be made of other materials that have flexibility, water permeability, and water retention, such as a nonwoven fabric. As shown in Figs. 1, 2, 3, 4, and 5, the holder 10 has a holding groove 12 that is open on the upper surface 10a side and extends along the front-rear direction X. That is, the shape of the holder 10 is formed to be rectangular in a plan view, and is formed to be substantially convex in a front view with the width of the upper part being smaller than the width of the lower part, as shown mainly in Figs. 2 and 4. The upper surface 10a side of the holder 10 has the holding groove 12 that is a groove extending in the front-rear direction X, the upper part being opened by a substantially linear groove upper opening part 12a, and the space below it being a storage part that stores the test fish F. In addition, the front and rear ends of the holding groove 12 are opened as groove end opening parts 12b on the respective side surfaces 10b on the front and rear sides of the holder 10.

[0020] In the holder 10, the holding groove 12 is provided over the entire length from the rear end to the front end of the holder 10 so that the length in the front-rear direction X is longer than the entire length (the length from the tip of the mouth to the rear end of the tail fin) of the test fish F. For example, when the test fish F is a zebrafish with a total length of about 40 mm, the length of the holding groove 12 is desirably set to about 50 mm. The depth of the holding groove 12 is slightly greater than the vertical height of the test fish F. For example, when the test fish F is a zebrafish with a total length of approximately 40 mm, it is desirable to set the depth of the holding groove 12 within the range of 5 to 25 mm. The dimensional values ​​of the above-mentioned holding groove 12 may be changed as appropriate, for example, may be increased or decreased within a range of about 30%.

[0021] The test fish F can be inserted into the holding groove 12 of the holder 10 directly, for example, from the test fish insertion device 5 described below, but in order to minimize damage to the test fish F, a specified insertion tool 40 is used. As shown in Figs. 1, 2, and 3, the insertion tool 40 has a cylindrical discharge chute 42 extending downward, and is configured to discharge the test fish F inserted into the insertion port 41 opened upward from the discharge port 42a at the lower end of the discharge chute 42 together with the water W. That is, the insertion tool 40 does not adopt a configuration in which the test fish F slides from the insertion port 41 toward the discharge chute 42 in a pipe inclined position, but is configured to provide the insertion port 41 above the discharge chute 42 and guide the test fish F directly from the insertion port 41 into the discharge chute 42. Therefore, as shown in Figs. 4 and 5, the test fish F inserted into the insertion port 41 together with the water W by the test fish insertion device 5 described later is guided directly into the discharge chute 42 together with the water W without sliding inside the pipe inclined position, and then discharged from the discharge port 42a at the lower end of the discharge chute 42 toward the holding groove 12 of the holder 10. This reduces the burden and damage on the test fish F, and allows the test fish F to be stably placed into the holding groove 12.

[0022] In addition, it is desirable that the position where the test fish F is introduced by the test fish introducing device 5 in the introduction port 41 is one side in the front-rear direction X, which is the extension direction of the holding groove 12. That is, the test fish F generally tends to assume a posture along the water flow, and further has a tendency to assume a posture against the water flow. For this reason, the test fish F released from the test fish introducing device 5 assumes a posture along the front-rear direction X along the water flow of the water W released at the same time, and is released from the tail fin side against the water flow, and is introduced into the holding groove 12 from the test fish introducing part 12A on the side of the holding groove 12 that is closer to the introduction position by the test fish introducing device 5. Therefore, the test fish F released from the test fish introducing device 5 together with the water W into the holding groove 12 is introduced from the test fish introducing part 12A in an appropriate posture along the extension direction (front-rear direction X) of the holding groove 12. Furthermore, by inserting the test fish F into the holding groove 12 from the test fish inserting portion 12A with its tail fin first, the test fish F inserted into the holding groove 12 can be oriented with its mouth Fa facing the test fish inserting portion 12A as much as possible. In addition, inside the holding groove 12 where the test fish F is inserted together with the water W from the test fish inserting portion 12A of the holder 10, the test fish F is immersed in the water W, and a water flow is formed from the test fish inserting portion 12A to the other portion. Since the test fish F generally has a tendency to assume a posture against the water flow, the test fish F inserted into the holding groove 12 is likely to be oriented with its mouth Fa facing the test fish inserting portion 12A.

[0023] The upper surface 10a of the holder 10 is formed with a chute insertion recess 15 into which the discharge chute 42 of the inserting tool 40 is inserted from above, and the holding groove 12 is formed in the bottom 15a of the chute insertion recess 15. That is, as shown in Figs. 4 and 5, the cylindrical discharge chute 42 extending downward in the inserting tool 40 is inserted into the chute insertion recess 15 formed in the holder 10, and the lower end opening of the discharge chute 42 abuts against the bottom 15a of the chute insertion recess 15. By inserting the discharge chute 42 into the chute insertion recess 15 in this manner, the test fish F discharged from the discharge opening 42a at the lower end of the discharge chute 42 is prevented from falling out of the holder 10. Furthermore, the holder 10 can be easily positioned at an appropriate position relative to the inserting tool 40 by simply inserting the discharge chute 42 into the chute insertion recess 15. With these configurations, the test fish F discharged from the discharge chute 42 reliably enters the holding groove 12 formed in the bottom 15a of the chute insertion recess 15.

[0024] The width of the chute insertion recess 15 along the left-right direction Y perpendicular to the front-rear direction X in a plan view is set slightly smaller than the width of the discharge chute 42 along the left-right direction Y, as shown in Fig. 2. Therefore, when the discharge chute 42, which is slightly wider than the chute insertion recess 15, is inserted as shown in Fig. 4, the side walls 12d on both the left and right sides of the holding groove 12 in the holder 10 are pushed open to the left and right, and the width of the holding groove 12 formed between those side walls 12d is pushed open to the left and right slightly. In this state, the test fish F discharged through the discharge chute 42 can be smoothly introduced into the holding groove 12 of the holder 10.

[0025] The overall size of the holder 10 in this embodiment is approximately 50 mm in height in the up-down direction, approximately 100 mm in width in the left-right direction Y, and approximately 50 mm in thickness in the front-rear direction X, with reference to the front view shown in Fig. 2 and the left side view shown in Fig. 3. The size of the chute insertion recess 15 formed on the top surface 10a of the holder 10 is approximately 15 mm in depth in the up-down direction, and approximately 15 mm in width in the left-right direction Y.

[0026] 2 etc., in the holder 10, the holding groove 12 is formed to have a cross-sectional shape of a substantial isosceles triangle with the apex being a groove open portion 12a that is open to the bottom 15a of the upper chute insertion recess 15. The size of this holding groove 12 is such that the height in the up-down direction is approximately 15 mm, the width of the base in the left-right direction Y is approximately 10 mm, and the width of the groove open portion 12a is approximately 2 mm. When a test fish F is held inside the holding groove 12, which has a cross-sectional shape of a substantially isosceles triangle with the groove open portion 12a as the apex, the test fish F is gently held in a relatively wide space, and the width of the groove open portion 12a on the upper surface 10a side is narrower than the width of the space, so that the test fish F is suitably prevented from falling out of the groove open portion 12a. Furthermore, as shown in Fig. 7, if the user pinches the side walls 12d on both the left and right sides of the holding groove 12 from the outside with his or her fingers H, the test fish F can be even more suitably prevented from falling out of the holding groove 12.

[0027] 1 and 2, the retainer 10 is formed with a groove forming portion 18 in which the retaining groove 12 is formed, and a pair of side wing portions 19 extending to both sides from the lower left and right sides of the groove forming portion 18. More specifically, the side wing portions 19 each having a width of about 25 mm extend to both sides from the lower left and right sides of the groove forming portion 18 having a width of about 50 mm, and the lower surfaces of the groove forming portion 18 and the pair of side wing portions 19 are formed on the same plane. Furthermore, the side wing portions 19 are located in an area from the lower end surface of the groove forming portion 18 to a height of about 20 mm. The dimensional values ​​of the above-mentioned holder 10 may be changed as appropriate, for example, may be increased or decreased within a range of about 30%.

[0028] 1, 2, and 3, the holder installation case 30 is configured as a container-like holder installation section that is detachably installed with the holder 10 housed therein. That is, as also shown in FIGS. 4 and 5, the holder installation case 30 is configured as a holder housing / water storage section in which the bottom of the square cylindrical outer peripheral wall section 31 is closed with a bottom plate section 34, water W is stored inside the outer peripheral wall section 31, and the holder 10 inserted from above is housed inside the holder installation case 30 in a holder installation state in which the holder 10 is installed in the holder installation case 30 and is immersed in the stored water W inside. When accommodating the holder 10 in the holder installation case 30, the inner dimensions of the outer wall 31 can be set appropriately to be approximately the same as the outer dimensions of the holder 10, slightly smaller, or slightly larger, taking into consideration the support stability of the holder 10 against the outer wall 31 and the ease of attachment and removal.

[0029] The holder installation case 30 has a pair of side wall portions 32 arranged on the front and rear sides when viewed from the holder 10 in the holder installed state, and a pair of side wall portions 33 arranged on the left and right sides when viewed from the holder 10 in the holder installed state, and this pair of left and right side wall portions 33 and the pair of front and rear side wall portions 32 form a cylindrical outer wall portion 31 that surrounds the holder 10 in the holder installed state. Each of the pair of front and rear side wall portions 32 extends along the front and rear side surfaces 10b of the holder 10 when the holder is installed, preventing the test fish F from falling out of the holding groove 12 through the front and rear groove end opening portions 12b of the holding groove 12. On the other hand, the pair of left and right side wall portions 33 are flat plates extending along a vertical plane parallel to both the left and right side surfaces 10c of the holder 10 when the holder is installed, and the pair of side wall portions 33 are in close contact with both the left and right side surfaces 10c of the holder 10.

[0030] 5, on both the front and rear sides of the holder 10 in the installed state, a mouth protrusion gap S is provided between the gap side wall portion 35, which is the side wall portion 32, and the groove end open portion 12b, which allows the mouth Fa of the test fish F held in the holding groove 12 to protrude from the groove end open portion 12b. That is, in this embodiment, of the front and rear sides of the holder 10 in the installed state, a mouth protrusion gap S is provided on the side closer to the test fish insertion site 12A, and a mouth protrusion gap S is also provided on the side farther from the test fish insertion site 12A.

[0031] Furthermore, in the holder installation case 30, the gap sidewalls 35 provided on the front and rear sides of the holder 10 are composed of an upper portion 35a located above the height position of the bottom surface 12c of the holding groove 12, and a lower portion 35b located below the height position of the bottom surface 12c, with the height position of the bottom surface 12c as the boundary. The upper portion 35a of the gap sidewalls 35 extends along a vertical plane parallel to the side surface 10b of the holder 10 at a position spaced apart by several mm from the groove end open portion 12b in the holder installation state. As a result, in the holder installation state, a mouth tip protrusion gap S having a width of several mm along the front-rear direction X is interposed between the gap sidewalls 35 and the groove end open portion 12b. On the other hand, the lower portion 35b of the gap sidewall portion 35 extends in close contact with the side surface 10b of the holder 10 in the holder installed state. This allows the holder 10 to be stably held by the lower portions 35b of the front and rear gap sidewall portions 35 in the holder installed state. Furthermore, the width of the groove end opening portion 12b along the front-to-rear direction X is set so that only the mouth tip Fa of the test fish F can protrude, and for example, when the test fish F is a zebrafish, it is desirable to set it to about 2 mm.

[0032] Then, as shown in Fig. 5, when the test fish F is put into the holding groove 12 together with the water W, the test fish F put into the holding groove 12 is in a state of being moderately immersed in the water W. Furthermore, fish have a habit of moving on their own to a position where their snout Fa touches the wall and settling down. For these reasons, as shown in Fig. 5, the test fish F immediately after being put into the holding groove 12 tends to move on its own in the direction toward the gap side wall 35 on the snout Fa side, and this movement results in a snout protruding state in which the snout Fa protrudes from the groove end open portion 12b into the snout protrusion gap S by about a few mm (about 2 mm). Furthermore, since a mouth protrusion gap S is provided on both the front and rear sides of the holding groove 12, even if the orientation of the test fish F inside the holding groove 12 is not determined, the mouth Fa of the test fish F can be almost reliably protruded into one of the mouth protrusion gaps S to put it in a mouth protruding state.

[0033] In addition, when the front or rear portion of the holding groove 12 is set as the test fish insertion site 12A where the test fish F is inserted together with water W from the groove end opening 12a, and a mouth tip protrusion gap S is provided at least on the front or rear side of the holding device 10 when the holding device is installed, which is closer to the test fish insertion site 12A, as described above, the test fish F inserted into the holding groove 12 tends to be positioned with its mouth tip Fa facing the test fish insertion site 12A, so that the test fish F inserted into the holding groove 12 moves on its own in the direction of the mouth tip Fa, which is the test fish insertion site 12A, causing the mouth tip Fa to protrude from the groove end opening 12b into the mouth tip protrusion gap S provided on the side closer to the test fish insertion site 12A.

[0034] Then, when the holder 10 holding the test fish F is removed from the holder installation case 30 as shown in Fig. 7 and the test substance is orally administered to the test fish F in the above-mentioned mouth-protruding state as shown in Fig. 8, position adjustment for protruding the mouth Fa of the test fish F held inside the holding groove 12 from the groove end open portion 12b is substantially unnecessary. Therefore, deterioration of the workability caused by the position adjustment of the test fish F inside the holding groove 12 is suppressed, and stress and damage to the test fish F caused by performing the position adjustment is reduced. Furthermore, since the test fish F tends to be positioned in the holding groove 12 with its mouth Fa facing the test fish insertion site 12A, when the holder 10 holding the test fish F is removed from the holder installation case 30 and a specified process is performed on the test fish F, there is almost no need to adjust the orientation of the test fish F, thereby further improving workability.

[0035] As shown in Fig. 4 and Fig. 5, the pair of front and rear side walls 32 adequately cover the groove end open parts 12b on the front and rear sides of the holding groove 12 in the holder 10, so that the water W is adequately retained inside the holding groove 12. That is, the pair of front and rear side walls 32 function as a water retaining means A that retains the water W inside the holding groove 12 in the holder 10 in the holder installation state. Then, the test fish F is introduced into the holding groove 12, in which the water W is adequately retained, together with the water W, so that the test fish F is always immersed in the water W, and therefore the test fish F remains inside the holding groove 12 in a stable posture without thrashing about. Therefore, the test fish F introduced into the holding groove 12 remains inside the holding groove 12 in a stable posture without thrashing about. As shown in Figure 5, when the test fish F is immersed in stagnant water W, the stagnant water W makes it easier for the test fish F to move in the direction of its mouth Fa, and the mouth Fa easily protrudes into the mouth protrusion gap S, making it unnecessary or simplified to adjust the position of the test fish F held in the holding groove 12 during oral administration as shown in Figure 8.

[0036] In this embodiment, the entire outer wall 31 of the holder installation case 30 is made of a transparent material. That is, since the side wall 32 is made of a transparent material, the state of the test fish F remaining inside the holding groove 12 can be observed from the outside through the side wall 32 and the groove end open portion 12b blocked by it. In this embodiment, the entire outer wall 31 is made of a transparent material, but even if the outer wall 31 is made of a non-transparent material, the state of the test fish F remaining inside the holding groove 12 can be observed from above through the groove top open portion 12a. In addition, multiple types of holder installation cases 30 with different colors of the outer wall 31, etc., can be prepared for each type of treatment, etc., for the test fish F, to suppress contamination between each treatment.

[0037] In the outer peripheral wall portion 31, the minimum upper end height (height of the upper end portion 33a) of at least a part of the pair of left and right side wall portions 33 is set lower than the minimum upper end height (height of the upper end portion 32a) of at least a part of the pair of front and rear side wall portions 32. Specifically, the respective upper end portions 32a, 33a of the pair of front and rear side wall portions 32 and the pair of left and right side wall portions 33 are horizontally straight and of the same height as a whole. Furthermore, the upper end portions 33a of the pair of side wall portions 33 are set lower than the upper end portions 32a of the pair of front and rear side wall portions 32. 4, the holder installation case 30 is configured to store water W inside in a form in which the stored water W overflows to the outside from the entire upper end portions 33a of the pair of left and right side wall portions 33. That is, since the stored water W inside the holder installation case 30 overflows from the entire upper end portions 33a of the pair of left and right side wall portions 33, by positioning the height of the upper end portions 33a at a predetermined set water level WL, the water level of the stored water W inside the holder installation case 30 can be maintained at the set water level WL. The upper end portions 33a of a pair of left and right side wall portions 33, which form the lowest upper end portions of at least a portion of the outer peripheral wall portion 31, are positioned at the height of the set water level WL and function as a water level maintaining means B that maintains the water level of the stored water W in the holder installation case 30 at a predetermined set water level WL.

[0038] Furthermore, in the holder installation case 30 housing the holder 10 therein, the height of the upper end portions 32a of the pair of front and rear side walls 32 is higher than the height of the upper end portions 33a of the pair of left and right side walls 33, so that overflow of the stored water W occurs at the upper end portions 33a of the pair of left and right side walls 33, but overflow of the stored water W does not occur at the upper end portions 32a of the pair of front and rear side walls 32. As a result, the test fish F held inside the holding groove 12 is prevented from being guided by the overflow of the stored water W and escaping from the upper end portions 32a of the side walls 32.

[0039] The above-mentioned set water level WL is a water level above the bottom surface 12c of the retaining groove 12 in the holder 10 housed in the holder installation case 30, and is set to a water level below the vicinity of the groove upper open portion 12a in the holder 10 housed in the holder installation case 30. In the holder installation state shown in Fig. 4 and Fig. 5, the holder 10 is installed in a state immersed in the stored water W in the holder installation case 30, and the water level of the stored water W in the holder installation case 30 is maintained at a set water level WL above the bottom surface 12c of the holding groove 12, and the water W is moderately retained inside the holding groove 12. That is, the water level maintaining means B, which is functioned by the upper end portion 33a of the pair of peripheral side walls 33, functions as a water retaining means A that retains the water W inside the holding groove 12 in the holder 10 in the holder installation state. Then, the test fish F is introduced into the holding groove 12, where the water W is moderately retained, together with the water W, so that the test fish F is always immersed in the water W. Then, the test fish F introduced into the holding groove 12 is in a stable posture without thrashing about, and remains inside the holding groove 12.

[0040] 4 and 5, the water level of the stored water W in the holder installation case 30 is maintained at a set water level WL below the vicinity of the groove-top open portion 12a. Therefore, since there is no water W above the vicinity of the groove-top open portion 12a, the test fish F held inside the holding groove 12 of the holder 10 housed in the holder installation case 30 is prevented from escaping upward from the groove-top open portion 12a. Furthermore, the above-mentioned set water level WL is preferably set near the groove top opening 12a including a range from a height slightly above the groove top opening 12a to a height slightly below the groove top opening 12a, and it is even more preferable to set it at the same height as the groove top opening 12a.

[0041] The holder installation case 30 has an insertion depth regulating section C that prevents the insertion depth of the discharge chute 42 into the chute insertion recess 15 from exceeding a predetermined set insertion depth in the holder installation state shown in Fig. 4 and Fig. 5. That is, the insertion tool 40 has a flange section 43 that extends horizontally outward from the upper end side portion of the discharge chute 42. When the discharge chute 42 of the insertion tool 40 is inserted into the chute insertion recess 15 of the holder 10, the upper end portions 32a of the pair of front and rear side wall sections 32 that protrude upward from the pair of left and right side wall sections 33 in the outer peripheral wall section 31 come into contact with the lower surface of the flange section 43 of the insertion tool 40, thereby functioning as the insertion depth regulating section C, and preventing the insertion depth of the discharge chute 42 into the chute insertion recess 15 from exceeding the desired insertion depth. Therefore, even if the discharge chute 42 of the inserting device 40 is firmly inserted into the chute insertion recess 15 of the holding device 10, the lower end of the discharge chute 42 is prevented from pressing against the bottom 15a of the chute insertion recess 15 of the holding device 10, so that the state of the holding groove 12 with the groove upper opening portion 12a open to the bottom 15a can be maintained appropriately.

[0042] [Test fish feeding device] Next, each embodiment of the test fish inserting device 5 for inserting the test fish F into the holding groove 12 (one example of a test fish holding portion) of the test fish holding device described above will be described with reference to the drawings.

[0043] [First embodiment] As a first embodiment of the test fish throwing device 5, a detailed configuration of a test fish throwing device 50 will be described with reference to Figs. In this embodiment, the configurations relating to the aforementioned test fish holding device are given the same symbols in the drawings and descriptions thereof will be omitted.

[0044] As shown in Fig. 12, the test fish throwing device 50 of this embodiment is composed of a bottomed cylindrical container body 51 capable of accommodating a test fish F together with water W inside. As also shown in Figs. 9 to 11, the container body 51 is configured in the shape of an inverted quadrangular pyramid by combining a flat bottom plate 53 that is diamond-shaped in plan view with four flat side wall parts 52 that are inverted trapezoidal shapes with an upper base longer than a lower base and are erected in a posture that inclines outwardly toward the upper side from each side of the bottom plate part 53. Furthermore, as shown in the plan view of Fig. 11, the upper end part opens in a diamond shape whose width in the front-rear direction X is larger than its width in the left-right direction Y. As shown in Figure 14, etc., the upper edge portion on the front side (the left side in Figure 11) is a release edge portion 59 that releases the test fish F contained inside together with water W, and on the inner wall surface side of the container body 51, the corner where the side wall portions 52 arranged on both sides of the release edge portion 59 intersect is formed as a test fish release promotion groove portion 55 with an approximately V-shaped cross section that extends downward from the release edge portion 59 for a length equal to or greater than the total length of the test fish F.

[0045] Furthermore, the container body 51, which is diamond-shaped when viewed from above, has four corners formed by the intersecting side wall portions 52, and any of these corners can be used as the test fish release promotion groove portions 55.However, as shown in Figure 11, the front and rear corners located in the front-to-back direction X have the side wall portions 52 intersecting at a sharper angle on both sides than the left and right corners located in the left-to-right direction Y, and therefore can be effectively used as the test fish release promotion groove portions 55 in terms of stabilizing the posture of the test fish F, as described below. 11 and 12, the inner wall surface of the test fish release promoting groove portion 55 is provided with a pattern 56 (e.g., a striped pattern arranged along the front-rear direction X) that allows the test fish F contained therein to be visually recognized. Note that this pattern 56 only needs to be provided on at least the inner wall surface of the test fish release promoting groove portion 55, and may be provided on the entire inner wall surface of the container body 51, for example.

[0046] A sample fish throwing method (hereinafter referred to as "this throwing method") for throwing a sample fish F together with water W into the holding groove 12 using the sample fish throwing device 50 will be described with reference to Figs. 12 to 15. First, as shown in FIG. 12, a test fish F is placed inside the container body 51 together with water W. At this time, since the container body 51 has a wide mouth that expands in diameter toward the top, the test fish F and water W can be easily contained inside the container body 51.

[0047] 13 to 15, with the release edge 59 brought close to the edge of the insertion port 41, the container body 51 is gradually tilted in a manner of rotating the container body 51 around an axis that passes near the release edge 59 and is perpendicular to the extension direction of the test fish release promoting groove 55, thereby performing a container tilting and insertion operation in which the contents of the container body 51 are released from the release edge 59 and poured into the holding groove 12. By performing such a container tilting and insertion operation, the test fish F contained inside the container body 51 is released together with the water W from the release edge 59 of the container body 51 and inserted into the holding groove 12. In order to reduce the burden on the test fish F and enable the test fish F to be inserted into the holding groove 12 in a stable posture while improving the ease of inserting the test fish F into the holding groove 12, the test fish inserting device 50 is equipped with a test fish release promotion section D that promotes the release of the test fish F before the release of water W from inside the container body 51 is completed when the above-mentioned container tilting insertion operation is performed.

[0048] Specifically, when the container tilting operation is performed, the test fish release promotion groove 55 guides the test fish F toward the release edge 59 and forms a water flow WF toward the release edge 59, thereby functioning as the test fish release promotion section D. That is, when performing the container tilting insertion operation, as shown in Fig. 13, when the container body 51 starts to be tilted, the test fish F contained inside the container body 51 approaches and enters the test fish release promoting groove 55. This maintains the posture of the test fish F in a posture along the test fish release promoting groove 55. Then, when the tilt angle of the container body 51 (the angle of the central axis of the container body 51 with respect to the vertical direction) is increased and the release of water W from the release edge 59 is started, a water flow WF is formed in the test fish release promoting groove 55 toward the release edge 59 while maintaining a water depth sufficient for the test fish F to demonstrate its swimming ability. Then, in the test fish release promoting groove 55, the test fish F stabilizes in a posture against the water flow WF (a posture in which the mouth Fa faces the upstream side of the water flow WF). At this time, the water W released from the release edge 59 is introduced into the holding groove 12 from the test fish insertion site 12A side, so that a moderate amount of water W is retained inside the holding groove 12, forming a water flow WF flowing from the test fish insertion site 12A to the other site.

[0049] 14, when the inclination angle of the container body 51 is further increased, the water flow WF in the test fish release promotion groove 55 becomes stronger, and the strong water flow WF promotes the release of the test fish F contained inside the container body 51 from the release edge 59 before the release of the water W from inside the container body 51 is completed, and the test fish F is released from the release edge 59 by its tail fin while maintaining a stable posture. This makes it easier to insert the test fish F into the holding groove 12, improving workability. Furthermore, by allowing the test fish F moving from the test fish release promoting groove portion 55 to the release edge portion 59 to clearly see its relative movement with respect to the pattern 56, it is possible to encourage the test fish F to swim against the water current WF. Furthermore, the width of the test fish release promoting groove portion 55 can be set appropriately depending on the water depth that occurs in the test fish release promoting groove portion 55 when water W is released from the release edge portion 59. For example, by making the width of the test fish release promoting groove portion 55 relatively small, the water depth that occurs in the test fish release promoting groove portion 55 when water W is released from the release edge portion 59 can be configured to be relatively large, allowing the test fish F to fully demonstrate their swimming ability.

[0050] As shown in FIG. 15, water W continues to be smoothly introduced even after the test fish F is introduced into the holding groove 12. As a result, the test fish F held inside the holding groove 12 is kept immersed in water W for at least a certain period of time, so that the test fish F can be calmed without thrashing about, and stress and damage to the test fish F can be reduced. Furthermore, since water W is retained inside the holding groove 12, a water flow WF can be formed along the extension direction of the holding groove 12 while the test fish F held inside the holding groove 12 is kept immersed in water W to a depth sufficient for the test fish F to exhibit swimming ability. Therefore, the posture of the test fish F introduced inside the holding groove 12 is stabilized in a posture against the water flow WF.

[0051] Second Embodiment As a second embodiment of the test fish throwing device 5, a detailed configuration of a test fish throwing device 60 will be described with reference to Figs. In this embodiment, the method of introducing the test fish F together with the water W into the holding groove 12 using the test fish introducing device 60 is the same as in the first embodiment, so a description thereof will be omitted.

[0052] The specimen fish introducing device 60 of this embodiment is configured with a bottomed cylindrical container body 61 capable of accommodating specimen fish F together with water W, as shown in Fig. 19. The container body 61 is configured in an inverted pyramidal shape by combining a flat bottom plate part 63 in a teardrop shape (a shape with a part of an ellipse pointed at an apex) with the front side (left side in Figs. 16 to 18) as an apex in a plan view with a combination of the side wall part 62 erected in a posture inclined outwardly toward the upper side from the outer peripheral edge part of the bottom plate part 63, as shown in the plan view of Fig. 18. Furthermore, the upper end part opens in a teardrop shape with the front side (left side in Fig. 18) as an apex in a plan view. As shown in Figure 19, the upper edge portion on the front side (the left side of Figure 19) is a release edge portion 69 that releases the test fish F contained inside together with water W, and on the inner wall surface side of the container body 71, the corner where the side wall portions 62 arranged on both sides of the release edge portion 69 intersect is formed as a test fish release promotion groove portion 65 with an approximately V-shaped cross section that extends downward from the release edge portion 69 for a length equal to or greater than the total length of the test fish F. 18 and 19, the inner wall surface of the test fish release promotion groove portion 65 is provided with a pattern 66 (e.g., a striped pattern arranged along the front-rear direction X) that allows the test fish F contained therein to be visually recognized. Note that this pattern 66 only needs to be provided on at least the inner wall surface of the test fish release promotion groove portion 65, and may be provided on the entire inner wall surface of the container body 61, for example.

[0053] In the test fish introducing method in which the test fish F is introduced into the holding groove 12 together with water W using the test fish introducing device 60, similarly to the first embodiment described above, the test fish release promoting groove section 65 functions as the test fish release promoting section D by guiding the test fish F toward the release edge section 69 and forming a water flow WF toward the release edge section 69 when the container tilt introducing operation is performed. This reduces the burden on the test fish F, allowing the test fish F to be introduced into the test fish holding section in a stable posture, while improving the operability of introducing the test fish F into the inside of the test fish holding section.

[0054] Third Embodiment As a third embodiment of the test fish throwing device 5, a detailed configuration of a test fish throwing device 70 will be described with reference to Figs. 20 to 26. In this embodiment, the configurations relating to the aforementioned test fish holding device are given the same symbols in the drawings and descriptions thereof will be omitted.

[0055] As shown in Fig. 23, the test fish introducing device 70 of this embodiment is composed of a cylindrical, substantially rectangular container body 71 with a bottom that can accommodate a test fish F together with water W. As also shown in Figs. 20 to 22, the container body 71 is configured in a substantially rectangular parallelepiped shape by combining a flat bottom plate portion 73 that is substantially rectangular in plan view with a side wall portion 72 that is erected vertically from the outer peripheral edge portion of the bottom plate portion 73. Furthermore, as shown in the plan view of Fig. 22, the upper end portion opens in a substantially rectangular shape, and the upper edge portion on the front side of the opening (the left side in Fig. 22) protrudes forward to form a release edge portion 79 that releases the test fish F accommodated inside together with the water W. Furthermore, on the inner wall surface of the container body 71, a test fish release promotion groove portion 75 with an approximately V-shaped cross section is formed which extends downward from the release edge portion 79 for a length equal to or greater than the total length of the test fish F, and the bottom 75a of this test fish release promotion groove portion 75 is formed so as to slope outwardly as it goes upward further than the portions 72a on both sides of the test fish release promotion groove portion 75 on the inner wall surface of the container body 71. 22 and 23, a pattern 76 (e.g., a striped pattern arranged along the front-rear direction X) that allows the test fish F contained therein to be visually recognized is provided on the inner wall surface of the test fish release promotion groove portion 75. Note that this pattern 76 only needs to be provided on at least the test fish release promotion groove portion 75, and may be provided on the entire inner wall surface of the container body 71, for example.

[0056] A sample fish throwing method (hereinafter referred to as "this throwing method") for throwing a sample fish F together with water W into the holding groove 12 using a sample fish throwing device 70 will be described with reference to Figs. 23 to 26. First, as shown in FIG. 23, a test fish F is placed inside the container body 71 together with water W.

[0057] 24 to 26, with the release edge 79 brought close to the edge of the insertion port 41, the container body 71 is gradually tilted in a manner of rotating the container body 71 around an axis that passes near the release edge 79 and is perpendicular to the extension direction of the test fish release promoting groove 75, thereby performing a container tilting insertion operation in which the contents of the container body 71 are released from the release edge 79 and poured into the holding groove 12. By performing such a container tilting insertion operation, the test fish F contained inside the container body 71 is released together with the water W from the release edge 79 of the container body 71 and poured into the holding groove 12. In order to reduce the burden on the test fish F and enable the test fish F to be inserted into the holding groove 12 in a stable posture while improving the ease of inserting the test fish F into the holding groove 12, the test fish inserting device 70 is equipped with a test fish release promotion section D that promotes the release of the test fish F before the release of water W from inside the container body 71 is completed when the above-mentioned container tilting insertion operation is performed.

[0058] Specifically, when the container tilting operation is performed, the test fish release promotion groove 75 guides the test fish F toward the release edge 79 and forms a water flow WF toward the release edge 79, thereby functioning as the test fish release promotion section D. That is, when performing the container tilting insertion operation, as shown in Fig. 24, when the container body 71 starts to be tilted, the test fish F contained inside the container body 71 approaches and enters the test fish release promoting groove 75. This maintains the posture of the test fish F in a posture along the test fish release promoting groove 75. Then, when the tilt angle of the container body 71 (the angle of the central axis of the container body 71 with respect to the vertical direction) is increased and the release of water W from the release edge 79 is started, a water flow WF is formed in the test fish release promoting groove 75 toward the release edge 79 while maintaining a water depth sufficient for the test fish F to demonstrate its swimming ability. Then, in the test fish release promoting groove 75, the test fish F stabilizes in a posture against the water flow WF (a posture in which the mouth Fa faces the upstream side of the water flow WF). At this time, the water W released from the release edge 79 is introduced into the holding groove 12 from the test fish insertion site 12A side, so that a moderate amount of water W also remains inside the holding groove 12, forming a water flow WF flowing from the test fish insertion site 12A to the other site.

[0059] As shown in Fig. 25, when the inclination angle of the container body 71 is further increased, the bottom 75a of the test fish release promotion groove 75 is inclined toward the release edge 79 before the portions 72a on both sides of the bottom 75a. Then, the water flow WF in the test fish release promotion groove 75 becomes stronger, and the strong water flow WF promotes the release of the test fish F contained inside the container body 71 from the release edge 79 before the release of the water W from inside the container body 71 is completed, and the test fish F is released from the release edge 79 by its tail fin while maintaining a stable posture. This makes it easier to insert the test fish F into the holding groove 12, improving workability.

[0060] Furthermore, by allowing the test fish F moving from the test fish release promoting groove portion 75 to the release edge portion 79 to clearly see its relative movement with respect to the pattern 76, it is possible to encourage the test fish F to swim against the water current WF. Furthermore, the width of the test fish release promoting groove portion 75 can be set appropriately depending on the water depth that occurs in the test fish release promoting groove portion 75 when water W is released from the release edge portion 79.For example, by making the width of the test fish release promoting groove portion 75 relatively small, the water depth that occurs in the test fish release promoting groove portion 75 when water W is released from the release edge portion 79 can be configured to be relatively large, allowing the test fish F to fully demonstrate their swimming ability.

[0061] As shown in FIG. 26, when the inclination angle of the container body 71 is further increased, the portions 72a on both sides of the test fish release promotion groove portion 75 are inclined toward the release edge portion 79 side, slower than the bottom portion 75a of the test fish release promotion groove portion 75. Then, the water W remaining inside the container body 71 is released from the release edge portion 79, and the water W continues to be smoothly introduced into the holding groove 12 even after the test fish F is introduced. As a result, the test fish F held inside the holding groove 12 is kept immersed in the water W for at least a certain period of time, so that the test fish F can be calmed without thrashing about, and stress and damage to the test fish F can be reduced. Furthermore, since the water W is retained inside the holding groove 12, a water flow WF can be formed along the extension direction of the holding groove 12 while the test fish F held inside the holding groove 12 is kept immersed in the water W to a depth deep enough to allow the test fish F to exhibit swimming ability. Therefore, the posture of the test fish F placed inside the holding groove 12 is stabilized in a posture against the water flow WF.

[0062] [Fourth embodiment] As a fourth embodiment of the test fish throwing device 5, a detailed configuration of a test fish throwing device 80 will be described with reference to Figs. In this embodiment, the configurations relating to the aforementioned test fish holding device are given the same symbols in the drawings and descriptions thereof will be omitted.

[0063] The test fish throwing device 80 of this embodiment is configured with a bottomed cylindrical container body 81 capable of accommodating a test fish F together with water W, as shown in FIG. 30. Furthermore, a test fish storage container 83 smaller than the container body 81 and accommodating a test fish F together with water W is installed in the upper part of the inside of the container body 81. The container body 81 and the test fish storage container 83 are configured as containers with a discharge edge 89 as a spout in a part thereof, as shown in FIGS. 27 to 29, and the test fish storage container 83 is arranged on the upper side of the container body 81 with the respective discharge edges 89 overlapping. That is, the test fish storage container 83 functions as a partition that divides the inside of the container body 81 into an upper test fish storage space Af in which the test fish F is stored and which leads to the discharge edge 89, and a lower water storage space Aw in which no test fish F is stored and only water W is stored and which leads to the discharge edge 89. The bottom plate portion 84 of this test fish holding container 83 is provided inside the container body 81 in an upwardly inclined position toward the discharge edge portion 89. As shown in Figure 32, etc., the upper edge portion on the front side (left side in Figure 32) of the test fish introducing device 80 is a release edge portion 89 that releases the test fish F contained inside together with water W, and the inner wall surface side of the test fish holding container 83 is formed with a test fish release promotion groove portion 85 that extends downward from the release edge portion 89 for a length equal to or greater than the full length of the test fish F, has an approximately U-shaped cross section, and narrows in width toward the front. 29 and 30, a pattern 86 (e.g., a striped pattern arranged along the front-to-back direction X) that allows the test fish F contained therein to be visually recognized is provided on the inner wall surface of the test fish release promotion groove portion 85. Note that this pattern 86 only needs to be provided on at least the test fish release promotion groove portion 85, and may be provided on the entire inner wall surface of the test fish storage container 83, for example.

[0064] Furthermore, on the opposite side of the discharge edge 89 inside the container body 81, a support part 87 (an example of a partition swing support part) is provided to support the lower edge part of the test fish container 83 on the opposite side of the discharge edge 89 so that the test fish container 83 can swing in a manner in which it is displaced up and down. That is, the support part 87 is configured to support the test fish container 83 so that it can swing freely between a discharge edge closing position (position shown in Figures 30 to 32) in which the test fish container 83 is positioned on the lower side and the communication part from the water accommodation space Aw to the discharge edge 89 is closed, and a discharge edge opening position (position shown in Figure 33) in which the test fish container 83 is positioned on the upper side and the communication part from the water accommodation space Aw to the discharge edge 89 is opened.

[0065] A sample fish throwing method (hereinafter referred to as "this throwing method") for throwing a sample fish F together with water W into the holding groove 12 using a sample fish throwing device 80 will be described with reference to Figs. 30 to 33. First, as shown in Figure 30, water W is contained in the test fish housing space Af and the water housing space Aw inside the container body 81, and a test fish F is contained in the test fish housing space Af inside the test fish housing container 83.

[0066] 31 to 33, with the release edge 89 brought close to the edge of the insertion port 41, the container body 81 is gradually tilted in a manner of rotating the container body 81 around an axis that passes near the release edge 89 and is perpendicular to the extension direction of the test fish release promoting groove 85, thereby performing a container tilting insertion operation in which the contents of the container body 81 are released from the release edge 89 and poured into the holding groove 12. By performing such a container tilting insertion operation, the test fish F contained inside the container body 81 is released together with the water W from the release edge 89 of the container body 81 and poured into the holding groove 12. In order to reduce the burden on the test fish F and enable the test fish F to be inserted into the holding groove 12 in a stable posture while improving the ease of inserting the test fish F into the holding groove 12, the test fish inserting device 80 is equipped with a test fish release promotion section D that promotes the release of the test fish F before the release of water W from inside the container body 81 is completed when the above-mentioned container tilting insertion operation is performed.

[0067] Specifically, when the container tilting and dropping operation is performed, the test fish release promotion groove 85 guides the test fish F toward the release edge 89 and forms a water flow WF toward the release edge 89, thereby functioning as a test fish release promotion section D. That is, when performing the container tilting insertion operation, as shown in FIG. 31, when the container body 81 starts to tilt, the test fish F accommodated in the test fish accommodation space Af inside the test fish accommodation container 83 tilting together with the container body 81 approaches and enters the test fish release promotion groove 85. This maintains the posture of the test fish F in a posture along the test fish release promotion groove 85. Then, when the tilt angle of the container body 81 (the angle of the central axis of the container body 81 with respect to the vertical direction) is increased and the release of water W from the release edge 89 is started, a water flow WF is formed in the test fish release promotion groove 85 toward the release edge 89 while maintaining a water depth sufficient for the test fish F to demonstrate its swimming ability. Then, in the test fish release promotion groove 85, the test fish F stabilizes in a posture against the water flow WF (posture with the mouth Fa facing the upstream side of the water flow WF). Furthermore, since the water W released from the release edge 89 is introduced into the holding groove 12 from the test fish insertion site 12A side, a moderate amount of water W is retained inside the holding groove 12, forming a water flow WF flowing from the test fish insertion site 12A to the other site. At this time, the test fish container 83 is in a closed release edge position due to its own weight and the weight of the contents, and the communication portion from the water storage space Aw to the release edge 89 is closed, so that the release of the water W stored in the water storage space Aw from the release edge 89 is suppressed.

[0068] 32, when the inclination angle of the container body 81 is further increased, the water flow WF in the test fish release promotion groove 85 becomes stronger, and the strong water flow WF promotes the release of the test fish F contained in the test fish holding container 83 from the release edge 89 before the release of the water W from inside the container body 81 is completed, and the test fish F is released from the release edge 89 by its tail fin while maintaining a stable posture. This makes it easier to insert the test fish F into the holding groove 12, improving workability. Furthermore, by allowing the test fish F moving from the test fish release promoting groove portion 85 to the release edge portion 89 to clearly see its relative movement with respect to the pattern 86, it is possible to encourage the test fish F to swim against the water current WF. Furthermore, the width of the test fish release promoting groove portion 85 can be set appropriately depending on the water depth that occurs in the test fish release promoting groove portion 85 when water W is released from the release edge portion 89.For example, by making the width of the test fish release promoting groove portion 85 relatively narrow, the water depth that occurs in the test fish release promoting groove portion 85 when water W is released from the release edge portion 89 can be made relatively large, allowing the test fish F to fully demonstrate their swimming ability.

[0069] As shown in Fig. 33, after the test fish F is put into the holding groove 12, the test fish container 83 is displaced upward due to its own weight and the weight of the contents being overcome by the water pressure from the water storage space Aw, and assumes a discharge edge open position, and the communication portion from the water storage space Aw to the discharge edge 89 is opened, so that the water W contained in the water storage space Aw is allowed to be discharged from the discharge edge 89. Then, even after the test fish F is put into the holding groove 12, the water W continues to be smoothly introduced. As a result, the test fish F held inside the holding groove 12 is kept immersed in the water W for at least a certain period of time, so that the test fish F is calmed without thrashing about, and stress and damage to the test fish F can be reduced. Furthermore, since water W is retained inside the holding groove 12, a water flow WF can be formed along the extension direction of the holding groove 12 while the test fish F held inside the holding groove 12 is immersed in the water W to a depth sufficient for the fish to be able to demonstrate its swimming ability. Therefore, the posture of the test fish F placed inside the holding groove 12 is stabilized in a posture against the water flow WF.

[0070] Fifth embodiment As a fifth embodiment of the test fish throwing device 5, a detailed configuration of a test fish throwing device 90 will be described with reference to Figs. In this embodiment, the configurations relating to the aforementioned test fish holding device are given the same symbols in the drawings and descriptions thereof will be omitted.

[0071] The test fish throwing device 90 of this embodiment is configured with a bottomed cylindrical container body 91 capable of accommodating a test fish F together with water W, as shown in FIG. 37. The container body 91 is configured as a container having a discharge edge 99 as a spout, as shown in FIGS. 34 to 36. Furthermore, a partition plate 92 is provided inside the container body 91 to divide the inside into upper and lower parts. That is, the partition plate 92 functions as a partition that divides the inside of the container body 91 into an upper test fish accommodation space Af in which the test fish F is accommodated and which leads to the discharge edge 99, and a lower water accommodation space Aw in which no test fish F is accommodated and only water W is accommodated and which leads to the discharge edge 99. The partition plate 92 is provided inside the container body 91 in an attitude inclined upward toward the discharge edge 99. As shown in Figure 39, the upper edge portion on the front side (left side in Figure 39) of the test fish introducing device 90 is a release edge portion 99 that releases the test fish F contained inside together with water W, and the inner wall surface side of the test fish housing space Af is formed with a test fish release promotion groove portion 95 that extends downward from the release edge portion 99 for a length equal to or greater than the full length of the test fish F, has a roughly U-shaped cross section, and narrows in width toward the front. 36 and 37, the inner wall surface of the test fish release promotion groove portion 95 is provided with a pattern 96 (e.g., a striped pattern arranged along the front-to-back direction X) that allows the test fish F housed therein to be visually recognized. Note that this pattern 96 only needs to be provided on at least the test fish release promotion groove portion 95, and may be provided on the entire inner wall surface of the test fish housing space Af, for example.

[0072] In addition, on the opposite side of the discharge edge 99 of the partition plate 92, a plurality of communication holes 94 are formed to communicate the upper test fish accommodation space Af and the lower water accommodation space Aw. The shape of each communication hole 94 can be changed as appropriate, but it is preferable to set the size to a size that allows the flow of water W and air while preventing the passage of the test fish F. Furthermore, a water discharge port 93 is also formed on the edge of the partition plate 92 on the discharge edge 99 side to communicate the upper test fish accommodation space Af and the lower water accommodation space Aw. The shape of the water discharge port 93 is a slit extending along the left-right direction Y in order to appropriately suppress the discharge of the water W contained in the water accommodation space Aw when it is discharged from the discharge edge 99 through the water discharge port 93 and make the discharge of the water W uniform in the left-right direction Y. Furthermore, the shape of the water outlet 93 can be changed as appropriate, but it is desirable to set its size to one that prevents the test fish F from passing through while allowing the flow of water W and air.

[0073] A sample fish throwing method (hereinafter referred to as "this throwing method") for throwing a sample fish F together with water W into the holding groove 12 using a sample fish throwing device 90 will be described with reference to Figs. 37 to 40. 37, water W is accommodated in the test fish accommodation space Af and the water accommodation space Aw inside the container body 91, and a test fish F is accommodated in the test fish accommodation space Af. The water W supplied to the test fish accommodation space Af is supplied to the water accommodation space Aw through a communication hole 94 formed in the partition plate portion 92.

[0074] 38 to 40, with the release edge 99 brought close to the edge of the insertion port 41, the container body 91 is gradually tilted in a manner of rotating the container body 91 around an axis that passes near the release edge 99 and is perpendicular to the extension direction of the test fish release promoting groove 95, thereby performing a container tilting and insertion operation in which the contents of the container body 91 are released from the release edge 99 and poured into the holding groove 12. By performing such a container tilting and insertion operation, the test fish F contained inside the container body 91 is released together with the water W from the release edge 99 of the container body 91 and inserted into the holding groove 12. In order to reduce the burden on the test fish F and enable the test fish F to be inserted into the holding groove 12 in a stable posture while improving the ease of inserting the test fish F into the holding groove 12, the test fish inserting device 90 is equipped with a test fish release promotion section D that promotes the release of the test fish F before the release of water W from inside the container body 91 is completed when the above-mentioned container tilting insertion operation is performed.

[0075] Specifically, when the container tilting and dropping operation is performed, the test fish release promotion groove portion 95 guides the test fish F toward the release edge portion 99 and forms a water flow WF toward the release edge portion 99, thereby functioning as the test fish release promotion portion D. That is, when performing the container tilting insertion operation, as shown in Fig. 38, when the container body 91 starts to be tilted, the test fish F accommodated in the test fish accommodation space Af on the upper side of the partition plate portion 92 approaches and enters the test fish release promotion groove portion 95. This maintains the posture of the test fish F in a posture along the test fish release promotion groove portion 95. Then, when the tilt angle of the container body 91 (the angle of the central axis of the container body 91 with respect to the vertical direction) is increased and the release of water W from the release edge portion 99 is started, a water flow WF is formed in the test fish release promotion groove portion 95 toward the release edge portion 99 while maintaining a water depth sufficient for the test fish F to demonstrate its swimming ability. Then, in the test fish release promotion groove portion 95, the test fish F stabilizes in a posture against the water flow WF (a posture in which the mouth Fa faces the upstream side of the water flow WF). Furthermore, since the water W released from the release edge 99 is introduced into the holding groove 12 from the test fish insertion site 12A side, a moderate amount of water W is retained inside the holding groove 12, forming a water flow WF flowing from the test fish insertion site 12A to the other site. At this time, the water W contained in the water containing space Aw is also discharged from the discharge edge 99 through the water discharge port 93, but because the opening of the water discharge port 93 is relatively small, the discharge of the water W is suppressed. When the water W contained in the water containing space Aw is discharged through the water discharge port 93, the communication hole 94 functions as an air introduction hole for introducing air into the water containing space Aw in an amount equivalent to the discharged water W.

[0076] 39, when the inclination angle of the container body 91 is further increased, the water flow WF in the test fish release promotion groove 95 becomes stronger, and the strong water flow WF promotes the release of the test fish F contained in the test fish containment space Af from the release edge 99 before the release of the water W from inside the container body 91 is completed, and the test fish F is released from the release edge 99 by its tail fin while maintaining a stable posture. This makes it easier to insert the test fish F into the holding groove 12, improving workability. Furthermore, by allowing the test fish F moving from the test fish release promoting groove portion 95 to the release edge portion 99 to clearly see its relative movement with respect to the pattern 96, it is possible to encourage the test fish F to swim against the water current WF. Furthermore, the width of the test fish release promoting groove portion 95 can be set appropriately depending on the water depth that occurs in the test fish release promoting groove portion 95 when water W is released from the release edge portion 99.For example, by making the width of the test fish release promoting groove portion 95 relatively narrow, the water depth that occurs in the test fish release promoting groove portion 95 when water W is released from the release edge portion 99 can be made relatively large, allowing the test fish F to fully demonstrate their swimming ability.

[0077] As shown in FIG. 40, even after the test fish F is put into the holding groove 12, the water W stored in the water storage space Aw continues to be smoothly introduced through the water outlet 93. As a result, the test fish F held inside the holding groove 12 is kept immersed in the water W for at least a certain period of time, so that the test fish F can be calmed without thrashing about, and stress and damage to the test fish F can be reduced. Furthermore, since the water W is retained inside the holding groove 12, the test fish F held inside the holding groove 12 can be immersed in the water W to a depth sufficient to allow the test fish F to exhibit swimming ability, and a water flow WF can be formed along the extension direction of the holding groove 12. Therefore, the posture of the test fish F put into the holding groove 12 is stabilized in a posture against the water flow WF.

[0078] Other Embodiments Other embodiments of the present invention will be described below. Note that the configurations of the embodiments described below are not limited to being applied alone, but may also be applied in combination with the configurations of other embodiments.

[0079] (1) In the above embodiment, the test fish introducing device 5 has been described as introducing the test fish F together with water W into the holding groove 12 of the test fish holder 10, but it may also be configured to introduce the test fish F together with water W into a test fish holding portion of another shape.

[0080] (2) In the above embodiment, the test fish F was introduced into the holding groove 12 of the holder 10 together with the water W using an introduction tool 40, but the configuration of the introduction tool 40 can be modified as appropriate, and the test fish F may be introduced into the holding groove 12 of the holder 10 together with the water W by another means without using such an introduction tool 40.

[0081] (3) In the above embodiment, the test fish release promoting groove portions 55, 65, 75, 85, 95 are configured to function as the test fish release promoting portion D by guiding the test fish F toward the release edge portion 59, 69, 79, 89, 99 when the container tilting insertion operation is performed and by forming a water flow WF toward the release edge portion 59, 69, 79, 89, 99. However, instead of the test fish release promoting groove portions 55, 65, 75, 85, 95, a mechanical portion may be provided as the test fish release promoting portion D, for example, which operates in conjunction with the container tilting insertion operation to push out the test fish F. [Explanation of symbols]

[0082] 5 Test fish feeding device 12 Retaining groove (test fish retaining part) 51 Container body 55 Test fish release promotion groove 59 Emission edge 60 Test fish feeding device 61 Container body 65 Test fish release promotion groove 69 Emission Edge 70 Test fish feeding device 71 Container body 72a Both sides 75 Test fish release promotion groove 75a bottom 79 Emission Edge 80 Test fish feeding device 81 Container body 83 Test fish container (compartment) 85 Test fish release promotion groove 87 Support section (partition body swing support section) 89 Emission Edge 90 Test fish feeding device 91 Container body 92 Partition plate section (partition body) 95 Test fish release promotion groove 99 Emission Edge Af Test fish housing space Aw Water storage space D Test fish release promotion department F Test fish W water WF water flow

Claims

1. A test fish inserting device for inserting a test fish together with water into a holding groove from an opening on the upper surface side of the holding groove that holds the test fish therein, The container body is a cylindrical container body with a bottom that can accommodate the test fish together with water. The inside of the container body is divided into an upper test fish storage space in which the test fish are stored and which is connected to a predetermined release edge located at the upper edge of the container body, and a lower water storage space in which the test fish are not stored and which contains only water and which is connected to the release edge. A partition is provided inside the container body in an upwardly inclined position toward the release edge, With the test fish contained in the container body together with water, a container tilting and pouring operation is performed in which the container body is tilted and the contents of the container body are poured into the holding groove, whereby the test fish contained in the container body is released together with water from the release edge and poured into the holding groove, When the container tilting insertion operation is performed, the partition body reaches a tilted release state in which it descends toward the release edge before the inner wall surface of the container body, thereby releasing the test fish together with water from the release edge before water is completely released from inside the container body.

2. a partition swing support portion that swingably supports the partition between a discharge edge portion closing position in which the communicating portion from the water storage space to the discharge edge portion is closed and a discharge edge portion opening position in which the communicating portion from the water storage space to the discharge edge portion is opened, The test fish introducing device of claim 1, wherein when the container tilting insertion operation is performed, before the test fish contained in the test fish housing space is released, the partition body is in the release edge closed position, thereby suppressing the release of water contained in the water housing space from the release edge, and after the test fish contained in the test fish housing space is released, the partition body is in the release edge open position, thereby allowing the release of water contained in the water housing space from the release edge.

Images