A device for screening eriocheir sinensis tolerance to low oxygen

Abstract

The utility model discloses a kind of Chinese mitten crab low oxygen tolerance screening devices, it is related to Chinese mitten crab breeding technical field.Its structure includes low oxygen water tank, dissolved oxygen control device, lifting plate module, gradient escape passage plate and crab collection box;Low oxygen water tank upper end cover has water tank cover;Low oxygen water tank side wall is provided with passageway, and low oxygen water tank outer wall is located passageway through hinge rotation installation with passageway connecting port baffle;Gradient escape passage plate is overlapped between passageway and crab collection box;Lifting plate module includes draining mesh plate placed in the inside of low oxygen water tank and horizontal and is installed on the rocker of low oxygen water tank.The utility model is through the synergistic effect of water low oxygen stress, lifting plate disengagement water body, vibration disturbance, gradient passage escape, subsequently physiological biochemical index verification is carried out to screening individual, and individual with high low oxygen tolerance characteristics is screened out.

Description

Technical Field

[0001] This utility model belongs to the field of Chinese mitten crab farming technology, and in particular relates to a low-oxygen screening device for Chinese mitten crabs. Background Technology

[0002] Screening for low-oxygen tolerance in Chinese mitten crabs is crucial for addressing the frequent occurrence of low-oxygen environments in aquaculture, ensuring aquaculture efficiency and economic benefits (improving survival rates, reducing risks, and optimizing quality), meeting their physiological adaptation needs, and unlocking their potential. It also promotes technological innovation and green, sustainable development in aquaculture. This screening process is of key significance for enhancing the industry's resilience, economic efficiency, and eco-friendliness.

[0003] In existing technologies, the screening of aquatic animals for hypoxia tolerance is mostly done for fish and shrimp. Low oxygen conditions easily cause them to float belly-up or die, thus requiring manual labor to select surviving, hypoxia-tolerant individuals. This process is complex and physically demanding. Patent application CN201922135879.1 discloses a hypoxia-tolerant selection device for whiteleg shrimp, which removes dead individuals to screen for those tolerant. However, this method is not suitable for crustaceans like the Chinese mitten crab, where dead individuals are difficult to detect. Under hypoxia stress, dead Chinese mitten crabs are difficult to spot in the water, requiring external agitation for discovery. Furthermore, the half-lethal period of hypoxia is long, but prolonged hypoxia can easily lead to organ damage, which is detrimental to subsequent farming and reproduction. This invention, combining the strong climbing ability of the Chinese mitten crab with automated control, simulates natural stress environments to achieve efficient, low-cost, and low-damage breeding of stress-resistant varieties. Utility Model Content

[0004] The purpose of this invention is to provide a low-oxygen-tolerant screening device for Chinese mitten crabs. This device utilizes the synergistic effects of low-oxygen stress in water, a lifting plate detaching from the water, vibration disturbance, and escape via a sloped passage to screen and collect individuals with high low-oxygen tolerance.

[0005] To solve the above-mentioned technical problems, this utility model is achieved through the following technical solution:

[0006] This utility model relates to a low-oxygen screening device for Chinese mitten crabs, comprising a low-oxygen water tank, a dissolved oxygen control device, a lifting plate module, a slope escape channel plate, and a crab collection box; the low-oxygen water tank is covered with a tank lid; a channel opening is provided on one side wall of the low-oxygen water tank, and a channel connection baffle is rotatably installed on the outer wall of the low-oxygen water tank at the channel opening via a hinge; the slope escape channel plate overlaps between the channel opening and the crab collection box; the lifting plate module includes a drainage mesh plate placed inside the low-oxygen water tank and a rocker arm horizontally installed on the low-oxygen water tank; several ends of ropes are fixed to the rocker arm, and the other ends of the ropes are fixed to the drainage mesh plate.

[0007] As a preferred embodiment of this utility model, a ring of rubber strips is fastened and installed on the upper end of the low-oxygen water tank.

[0008] As a preferred technical solution of this utility model, the lower end side wall of the low oxygen water tank is provided with an inlet and outlet pipe and a valve.

[0009] As a preferred embodiment of this utility model, the dissolved oxygen control device includes a nitrogen injection system, a dissolved oxygen detector, and an oxygenation system.

[0010] As a preferred technical solution of this utility model, the bottom surface of the slope escape passage plate is covered with anti-slip non-woven fabric.

[0011] As a preferred embodiment of this utility model, a vibration motor is installed on one side wall of the low-oxygen water tank.

[0012] As a preferred embodiment of this utility model, the crab collecting box includes a main box and two expansion boxes; the main box is a rectangular box, and a rectangular through hole is provided on one opposite side wall of the main box to cooperate with the expansion box in a pull-out manner; the expansion box includes an expansion groove with an upper end and an opening communicating with the main box; a limiting protrusion is provided at the upper end of the expansion groove near its side opening; a support strip is fixed at the lower end of the expansion groove away from the corner of the main box; and a handle is installed on the expansion groove.

[0013] This utility model has the following beneficial effects:

[0014] This invention utilizes the synergistic effects of low oxygen stress in water, lifting plate detachment from the water body, vibration disturbance, and sloped passage escape to screen and collect individuals with high tolerance to low oxygen.

[0015] Of course, any product implementing this utility model does not necessarily need to achieve all of the advantages described above at the same time. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of this utility model, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the low-oxygen screening device for Chinese mitten crabs according to this utility model.

[0018] Figure 2 This is a structural diagram showing the crab collection box in its stored state.

[0019] Figure 3 A schematic diagram of the crab collection box in its unfolded state.

[0020] Figure 4 This is a structural diagram of the main box.

[0021] Figure 5 This is a structural diagram of the extended box.

[0022] The attached diagram lists the components represented by each number as follows:

[0023] 1-Low-oxygen water tank, 101-Tank cover, 102-Channel connection port baffle, 103-Inlet and outlet pipes and valves, 2-Dissolved oxygen control device, 201-Nitrogen injection system, 202-Dissolved oxygen detector, 203-Oxygenation system, 3-Lifting plate module, 301-Rock arm, 302-Draining mesh plate, 4-Vibration motor, 5-Slope escape passage plate, 501-Anti-slip non-woven fabric, 6-Crab collection box, 61-Main box body, 611-Rectangular through hole, 62-Extension box body, 621-Extension groove, 622-Limiting protrusion, 623-Support strip, 624-Handle. Detailed Implementation

[0024] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present utility model. Specific Implementation Example 1:

[0026] Please see Figure 1-5 As shown, this utility model is a low-oxygen screening device for Chinese mitten crabs, including a low-oxygen water tank 1, a dissolved oxygen control device 2, a lifting plate module 3, a slope escape channel plate 5, and a crab collection box 6. The low-oxygen water tank 1 is covered with a tank cover 101. A channel opening is provided on one side wall of the low-oxygen water tank 1, and a channel connection baffle 102 is rotatably installed on the outer wall of the low-oxygen water tank 1 at the channel opening via a hinge. The slope escape channel plate 5 overlaps between the channel opening and the crab collection box 6. The lifting plate module 3 includes a drainage mesh plate 302 placed inside the low-oxygen water tank 1 and a rocker arm 301 horizontally installed on the low-oxygen water tank 1.

[0027] Several ropes are fixed to one end of the lever 301, and the other end of the ropes is fixed to the drainage mesh plate 302. By manually cranking the lever 301, the ropes are wound up, causing the drainage mesh plate 302 to rise upwards, raising it by 20cm-40cm, thus lifting the crab out of the water.

[0028] The low-oxygen water tank 1 is supported by a transparent acrylic panel, allowing for easy observation of its internal condition. A rubber strip is fitted around the top of the low-oxygen water tank 1 to ensure a relatively tight seal when the tank lid 101 is closed. For easy addition of water or drainage, inlet and outlet pipes and a valve 103 are located on one side wall at the lower end of the low-oxygen water tank 1.

[0029] The dissolved oxygen control device 2 includes a nitrogen injection system 201, a dissolved oxygen detector 202, and an oxygenation system 203. The nitrogen injection system 201 includes a nitrogen tank, a first air duct, and a first aeration head. The first air duct connects the nitrogen tank output and the first aeration head, reducing dissolved oxygen levels in the water by controlling the nitrogen flow rate. The dissolved oxygen detector 202 includes an oxygen content detection unit and a wired dissolved oxygen sensor with a high-precision probe for real-time monitoring of dissolved oxygen. The oxygenation system 203 includes an air pump, a second air duct, and a second aeration head. The second air duct connects the air pump output and the second aeration head, used for oxygenation during the adaptation period, supplementing dissolved oxygen when the dissolved oxygen concentration is below 1 mg / L, and quickly restoring the dissolved oxygen level to normal after experiments. The first air duct, the second air duct, and the wired dissolved oxygen sensor cable pass through the side wall of the low-oxygen tank 1. The first aeration head, the second aeration head, and the dissolved oxygen sensor head are all located below the perforated mesh plate 302.

[0030] The bottom surface of the slope escape passage 5 is covered with anti-slip non-woven fabric 501. The slope escape passage 5 has an inclination angle of 10°-30°, a length of 80cm, and is made of anti-slip non-woven fabric 501 (weight 30-50g / m², coefficient of friction ≥0.6). The slope increases the physical exertion threshold, allowing only physically strong individuals to pass through.

[0031] One of the low-oxygen water tanks 1 has a vibration motor 4 installed on one side wall. The vibration stimulates the water, simulating a natural threat (such as a predator), and triggers escape behavior.

[0032] The crab collecting box 6 includes a main box body 61 and two expansion boxes 62. The main box body 61 is rectangular, and a rectangular through hole 611 is provided on one opposite side wall of the main box body 61 to allow the expansion boxes 62 to be pulled out. The expansion boxes 62 include an expansion groove 621 with an upper end and an opening communicating with the side opening of the main box body 61. A limiting protrusion 622 is provided at the upper end of the expansion groove 621 near its side opening. A support strip 623 is fixed at the lower end of the expansion groove 621 away from the corner of the main box body 61. A handle 624 is installed on the expansion groove 621. The two expansion boxes 62 of the crab collecting box 6 can be pulled outward to expand the storage space and facilitate the quick collection of more crabs.

[0033] This utility model describes the low-oxygen tolerance screening process for Chinese mitten crabs.

[0034] 1. Pre-acclimatization: Chinese mitten crabs were fasted for 24 hours before the experiment to avoid interference with metabolic oxygen consumption. A low-oxygen tank was filled to a depth of 30 cm, and the crabs were placed in the low-oxygen area to acclimatize to the environment for 12 hours.

[0035] 2. Hypoxia stress: Activate nitrogen injection system 201 to reduce dissolved oxygen to 1.5 mg / L (±0.2 mg / L) within 30 minutes, then stop nitrogen injection. Dissolved oxygen detector 202 continuously monitors dissolved oxygen. If dissolved oxygen is higher than 2 mg / L, activate nitrogen injection. If dissolved oxygen is lower than 1 mg / L, activate oxygenation system 203 to maintain low oxygen concentration for 6 hours.

[0036] 3. Stress trigger: The hand crank 301 rotates the rope, which drives the drain mesh plate 302 upward, raising it by 20cm-40cm, so that the crab body is removed from the water, and the vibration motor 4 is started; the channel connection port baffle 102 is flipped upward to open.

[0037] 4. Escape Selection: When Chinese mitten crabs are in a low-oxygen environment, they will climb onto land or surface to try to escape the water. Severe hypoxia can lead to motor incoordination and even coma. In this experiment, the dominant individuals climbed to the crab collection box 6 via the sloping escape passage board 5. The first 20% of individuals were collected as those with high hypoxia tolerance.

[0038] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0039] The preferred embodiments of this utility model disclosed above are merely illustrative of the present utility model. These preferred embodiments do not exhaustively describe all details, nor do they limit the utility model to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of this utility model, thereby enabling those skilled in the art to better understand and utilize it. This utility model is limited only by the claims and their full scope and equivalents.

Claims

1. A low-oxygen tolerance screening device for Chinese mitten crab, characterized in that: It includes a low-oxygen water tank (1), a dissolved oxygen control device (2), a lifting plate module (3), a slope escape passage plate (5), and a crab collection box (6). The low-oxygen water tank (1) is covered with a water tank cover (101); a passage opening is provided on one side wall of the low-oxygen water tank (1), and a passage connection baffle (102) is installed on the outer wall of the low-oxygen water tank (1) at the passage opening by means of a hinge; the slope escape passage plate (5) overlaps between the passage opening and the crab collection box (6); The lifting plate module (3) includes a drainage mesh plate (302) placed inside the low oxygen water tank (1) and a rocker arm (301) horizontally installed on the low oxygen water tank (1); one end of several ropes is fixed on the rocker arm (301), and the other end of the ropes is fixed on the drainage mesh plate (302).

2. The low-oxygen tolerance screening device for Chinese mitten crabs according to claim 1, characterized in that, A rubber strip is fastened to the upper end of the low-oxygen water tank (1).

3. The low-oxygen tolerance screening device for Chinese mitten crabs according to claim 1, characterized in that, The low-oxygen water tank (1) is provided with an inlet and outlet pipe and a valve (103) on one side wall at the lower end.

4. The low-oxygen tolerance screening device for Chinese mitten crabs according to claim 1, characterized in that, The dissolved oxygen control device (2) includes a nitrogen injection system (201), a dissolved oxygen detector (202), and an oxygenation system (203).

5. The low-oxygen tolerance screening device for Chinese mitten crabs according to claim 1, characterized in that, The bottom surface of the slope escape passage slab (5) is covered with anti-slip non-woven fabric (501).

6. The low-oxygen tolerance screening device for Chinese mitten crabs according to claim 1, characterized in that, A vibration motor (4) is installed on one side wall of the low-oxygen water tank (1).

7. The low-oxygen tolerance screening device for Chinese mitten crabs according to claim 1, characterized in that, The crab collection box (6) includes a main box body (61) and two expansion boxes (62); the main box body (61) is a rectangular box body, and a rectangular through hole (611) is provided on one opposite side wall of the main box body (61) to be pulled out and fitted with the expansion box body (62); the expansion box body (62) includes an expansion groove (621) with an upper end and an opening communicating with the side opening of the main box body (61); a limit protrusion (622) is provided at the upper end of the expansion groove (621) near its side opening; a support strip (623) is fixed at the lower end of the expansion groove (621) away from the corner of the main box body (61); a handle (624) is installed on the expansion groove (621).

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