Embryo transplant gun and transplant method for sheep breeding

Abstract

The present invention discloses an embryo transplant gun and a transplant method for sheep breeding, which relate to the technical field of embryo transplantation, comprising: a transplant cylinder, a culture medium tube and a flexible catheter that are coaxially connected in sequence; a push injection assembly that is slidably arranged in the transplant cylinder, and the push injection assembly comprises: a propulsion rod with a predetermined rigidity; a spherical connector fixedly connected to the distal end of the propulsion rod; a piston that is slidably sleeved on the propulsion rod, and an annular groove is provided at one end of the piston away from the spherical connector; a phase change connector, and the phase change connector is embedded in the annular groove through low-temperature phase change to achieve a controllable detachable connection between the propulsion rod and the piston, and the whole has the advantages of bending adaptability, structural stability and sealing.

Description

Technical Field

[0001] The invention relates to the technical field of embryo transplantation, in particular to an embryo transplantation gun for sheep breeding and a transplantation method. Background Art

[0002] Embryo transfer, as an essential component of modern assisted reproductive technology, plays a key role in fields such as animal husbandry and medical research. The embryo transfer gun, a key instrument in the embryo transfer process, has a direct impact on the success rate and efficiency of embryo transfer.

[0003] Existing embryo transfer guns primarily consist of a gun body, a piston, and a flexible catheter. Their basic operating principle is to load embryonic fluid into the gun body and, by pushing the piston, deliver it along the flexible catheter to the target location, such as a sheep's uterus. Ideally, the piston's movement within the gun body should be smooth and stable, accurately pushing the embryonic fluid to the end of the flexible catheter and out smoothly.

[0004] However, in practice, existing embryo transfer guns have a problem with the embryonic fluid in the flexible catheter being difficult to deliver, which seriously affects the success rate of embryo transfer. After in-depth analysis and research, it was found that the core cause of this problem is the difficulty of the piston moving in the flexible catheter.

[0005] Existing flexible catheters are typically made of materials with a certain degree of flexibility to accommodate the curved passages within the animal body. However, these flexible materials tend to generate significant friction when in contact with the piston (especially when the flexible catheter is curved). As the piston moves within the flexible catheter, this friction hinders its forward movement, requiring greater force to push it.

[0006] Furthermore, existing flexible catheters typically feature a one-piece design, which presents significant limitations when used within the complex and tortuous passageways of the sheep body during embryo transfer. The sheep body's physiological structure is complex, with numerous narrow and curved areas, making it difficult for a one-piece flexible catheter to flexibly adapt to these complex passageways.

[0007] For example, during embryo transfer, when a flexible catheter needs to bend at a small angle at a specific location to avoid obstacles or accurately reach the target location, the integrated flexible catheter, due to its integral structural characteristics, cannot achieve precise bending adjustment. Operators often have difficulty accurately controlling the degree and direction of the flexible catheter's bend, resulting in difficulty in advancing the flexible catheter within the sheep's body. Forced bending may even cause unnecessary damage to the sheep's tissues, such as scratches and squeezing. This not only increases the sheep's pain but can also cause complications such as infection, affecting the effectiveness of the embryo transfer and the sheep's health.

[0008] Therefore, it is necessary to provide an embryo transplant gun and a transplant method for sheep breeding to solve the above problems. Summary of the Invention

[0009] To solve the above problems, the present invention provides the following technical solutions: an embryo transplant gun for sheep breeding, comprising: a transplant cylinder, a culture medium tube and a flexible catheter coaxially connected in sequence; a push injection assembly slidably arranged in the transplant cylinder; the push injection assembly includes: a propulsion rod with a predetermined rigidity; a spherical connector fixedly connected to the distal end of the propulsion rod; a piston slidably mounted on the propulsion rod, the end of the piston away from the spherical connector being provided with an annular groove; a phase change connector, the phase change connector being embedded in the annular groove to realize a controllable detachable connection between the propulsion rod and the piston.

[0010] Preferably, the inner diameter D3 of the flexible catheter, the inner diameter D2 of the culture medium tube and the inner diameter D1 of the transplant tube satisfy: D3<D2<D1, and the outer diameter D4 of the spherical connector satisfies: D4=D3.

[0011] Preferably, a heating element is provided on the outside of the propulsion rod.

[0012] Preferably, the propulsion rod includes an inner rod, and the outer fixing sleeve of the inner rod is provided with a support ring and an elastic ring, and the support ring and the elastic ring are distributed crosswise in sequence; wherein, the inner rod is made of a flexible heat-conducting material, and the support ring is made of a rigid heat-conducting material.

[0013] Preferably, the spherical connector is made of heat-insulating material.

[0014] Preferably, the flexible catheter is divided into at least two sections, which are connected by a telescopic ring bag. The interior of the telescopic ring bag is divided into at least four independent expansion and contraction spaces, each expansion and contraction space is supplied with air by a trachea, and the end of the trachea away from the telescopic ring bag is connected to a pressing bag, and the pressing bag is fixed to the transplant tube.

[0015] Preferably, an attached airway is fixed to the surface of the flexible catheter, and the attached airway and the outer surface of the flexible catheter together constitute an air guide channel, and the air guide channel is connected between the corresponding trachea and the telescopic ring bag, and the cross-section of the attached airway is an arc-shaped cross-section that matches the curvature of the outer wall of the flexible catheter.

[0016] A method for embryo transplantation for sheep breeding comprises the following steps:

[0017] S1. Establishing a bolus injection route: Delivering the transplant tube, culture medium tube, and flexible catheter through the sheep's vagina to the target site;

[0018] S2. Primary Push Injection: Insert the push-in assembly into the transfer tube and push the piston with the push rod to push the embryos in the culture medium tube into the flexible catheter.

[0019] S3. Phase change triggering: After the phase change connector undergoes a phase change and liquefies, the push rod is further pushed, thereby pushing the embryo in the flexible catheter into the sheep's uterus through the spherical connector.

[0020] S4. Withdrawal of instruments: Slowly remove the transplant tube, culture medium tube and flexible catheter to complete the embryo transfer operation.

[0021] Compared with the prior art, the present invention provides an embryo transplant gun and transplant method for sheep breeding, which has the following beneficial effects:

[0022] First, the push rod of the present invention adopts a cross-distributed structure of a flexible heat-conducting inner rod, a rigid heat-conducting support ring and an elastic ring, which has the advantages of bending adaptability, structural stability, cushioning and shock absorption, and heat conduction; and the spherical connector is made of heat-insulating material, which can protect the activity of the embryo, maintain the stability of the culture medium, ensure the accuracy of phase change and improve the performance of the instrument, ensuring that the embryo in the flexible catheter can be pushed into the sheep's uterus.

[0023] Second, the flexible catheter segments of the present invention are connected by telescopic ring bags, and the independent expansion and contraction spaces inside them can be independently controlled and the bending direction can be accurately adjusted. The trachea is connected to the pressing bag and fixed to the transplant tube, which is easy to operate and has good stability.

[0024] Third, the attached airway in the present invention has an arc-shaped cross-section that matches the curvature of the outer wall of the flexible catheter, forming an air guide channel to ensure stable gas transmission without increasing the outer diameter too much, thereby improving the overall instrument operation experience and transplantation success rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic diagram of the main structure of an embryo transplant gun for sheep breeding;

[0026] Figure 2 This is a schematic diagram of the structure of a flexible catheter in an embryo transfer gun for sheep breeding;

[0027] Figure 3 This is a schematic diagram of the structure of a push injection component in an embryo transfer gun for sheep breeding;

[0028] Figure 4 This is a schematic cross-sectional view of a flexible catheter in an embryo transfer gun for sheep breeding;

[0029] Figure 5 This is a schematic diagram of the structure of a propulsion rod in an embryo transfer gun for sheep breeding;

[0030] Figure 6 This is a flow chart of an embryo transfer method for sheep breeding;

[0031] In the figure: 1. Transplant tube; 2. Culture medium tube; 3. Flexible catheter; 4. Telescopic ring bag; 5. Trachea; 6. Pressing bag; 7. Pushing assembly; 8. Heating element; 9. Attached airway; 71. Push rod; 72. Piston; 73. Phase change connector; 74. Spherical connector; 711. Inner rod; 712. Support ring; 713. Elastic ring. DETAILED DESCRIPTION

[0032] The terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned description of the drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequential order. It should be understood that the terms used in this way can be interchangeable under appropriate circumstances, and this is merely a way of distinguishing the objects of the same attributes when describing them in the embodiments of the present application. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, so that the process, method, system, product or equipment comprising a series of units need not be limited to those units, but may include other units that are not clearly listed or inherent to these processes, methods, products or equipment.

[0033] Example: Please refer to Figures 1-6 In an embodiment of the present invention, an embryo transplant gun for sheep breeding is provided, comprising: a transplant cylinder 1, a culture medium tube 2 and a flexible catheter 3 coaxially connected in sequence; a push injection assembly 7 slidably arranged in the transplant cylinder 1; the push injection assembly 7 comprises: a propulsion rod 71 with a predetermined stiffness; a spherical connector 74 fixedly connected to the distal end of the propulsion rod 71; a piston 72 slidably mounted on the propulsion rod 71, and an annular groove is provided at one end of the piston 72 away from the spherical connector 74; a phase change connector 73, the phase change connector 73 is embedded in the annular groove through low-temperature phase change, thereby realizing a controllable and separable connection between the propulsion rod 71 and the piston 72.

[0034] The implementation includes the following steps:

[0035] S1. Establishing a push injection path: delivering the transplant tube 1, the culture medium tube 2, and the flexible catheter 3 to the target location through the sheep's vagina;

[0036] S2. Primary push injection: Insert the push injection assembly 7 into the transplant tube 1, push the piston 72 by the push rod 71, and then push the embryo in the culture medium tube 2 into the flexible catheter 3;

[0037] S3. Phase change trigger: After the phase change connector 73 undergoes phase change and liquefaction, the push rod 71 is continued to be pushed, thereby pushing the embryo in the flexible catheter 3 into the sheep's uterus through the spherical connector 74;

[0038] S4. Withdrawal of instruments: Slowly remove the transplant tube 1, culture medium tube 2 and flexible catheter 3 to complete the embryo transplantation operation.

[0039] It should be noted that in the prior art, embryonic fluid within the flexible catheter 3 is difficult to expel. However, in this embodiment, the collaborative design of a phased pushing mechanism and a spherical connector 74 solves the industry's problem of embryonic fluid remaining within the flexible catheter 3. First, piston 72 achieves an initial, stable push of embryonic fluid within the culture medium tube 2. Subsequently, body temperature-triggered liquefaction of the phase-change connector 73 automatically separates the push rod 71 from the piston 72, allowing the spherical connector 74 to be directly embedded within the flexible catheter 3. Its spherical geometric profile adapts to the curved shape of the flexible catheter 3, forming a dynamic seal with the wall of the flexible catheter 3 and applying uniform pressure to completely expel the embryonic fluid. This avoids leakage or embryo retention caused by deformation of the flexible catheter 3, which is common with conventional rigid pistons. Furthermore, the predetermined stiffness of the push rod 71 and the smooth surface of the spherical connector 74 reduce pushing resistance and the risk of embryo damage, while the body temperature-responsive nature of the phase-change connector 73 further simplifies the operation process, enabling precise control of the entire process from in vitro injection to intrauterine delivery, significantly improving the success rate of implantation and biocompatibility.

[0040] In other words, this embryo transplant gun has achieved breakthroughs in two core indicators: reducing embryo retention and protecting embryo activity. It is particularly suitable for embryo transplantation in small ruminants with deep and curved uterine horns such as sheep and goats.

[0041] It is worth mentioning that the piston 72 can provide effective guidance and support for the push rod 71 during the process of the spherical connector 74 pushing the embryo out of the flexible catheter 3. Because the piston 72 is very close to the flexible catheter 3, the connection structure between the piston 72 and the push rod 71 enables the push rod 71 to maintain a stable direction during the advancement process.

[0042] This guide support can prevent the propulsion rod 71 from deflecting or shaking during the propulsion process, ensuring that the spherical connector 74 can accurately advance along the direction of the flexible catheter 3 and accurately inject the embryo into the sheep's uterus.

[0043] In addition, it should be explained that the phase change connector 73 is a material that changes its physical state (solid-liquid) through temperature changes.

[0044] Preferably, the phase transition temperature is slightly lower than the sheep's body temperature, ensuring a rapid response in the body; it is non-toxic, biocompatible, and meets medical device standards.

[0045] For example, medical paraffin, gallium-indium alloy, and polycaprolactone.

[0046] In addition, the inner diameter D3 of the flexible catheter 3, the inner diameter D2 of the culture fluid tube 2 and the inner diameter D1 of the transplant tube 1 satisfy: D3<D2<D1, and the outer diameter D4 of the spherical connector 74 satisfies: D4=D3. Of course, the outer diameter of the piston 72 is equal to the inner diameter D2 of the culture fluid tube 2.

[0047] The smaller inner diameter of the flexible catheter 3 facilitates its flexible movement within the sheep's body, minimizing damage to the sheep's tissues while enabling precise delivery of the embryo to the target location. The larger inner diameter of the transplant tube 1 provides ample operating space for the push rod 71 and piston 72 to slide smoothly within the tube.

[0048] The outer diameter D4 of the spherical connector 74 is smaller than the inner diameter D2 of the culture fluid tube 2, allowing the spherical connector 74 to pass smoothly through the culture fluid tube 2 and enter the flexible conduit 3. After the phase change is triggered, the push rod 71 continues to push the spherical connector 74. Because the spherical connector 74 can adapt to the shape of the flexible conduit 3 and its outer diameter is smaller than the inner diameter of the culture fluid tube 2, it will not get stuck at the connection between the culture fluid tube 2 and the flexible conduit 3 due to its oversize.

[0049] Because the inner diameter D3 of the flexible conduit 3 is smaller than the outer diameter D2 of the piston 72, when the piston 72 moves to the connection between the flexible conduit 3 and the culture medium tube 2, the flexible conduit 3 acts as a limiter for the piston 72, preventing it from moving further forward into the flexible conduit 3. This limiter ensures that during the initial push injection, the piston 72 moves only within the culture medium tube 2, accurately pushing the embryo into the flexible conduit 3, without directly entering the flexible conduit 3. This prevents confusion or failure in the embryo push injection operation caused by the piston 72 entering the flexible conduit 3.

[0050] In this embodiment, a heating element 8 is provided on the outside of the propulsion rod 71 .

[0051] The heating element 8 can provide additional heat to the phase change connector 73, allowing it to reach the phase change temperature more quickly, thereby accelerating the phase change process and improving the efficiency and accuracy of the entire embryo transfer gun operation. The heating element 8 can be any one of a resistance wire heater, a semiconductor heater, and a flexible heating film.

[0052] In this embodiment, the propulsion rod 71 includes an inner rod 711, and the external fixed sleeve of the inner rod 711 is provided with a support ring 712 and an elastic ring 713, and the support ring 712 and the elastic ring 713 are cross-distributed in sequence; wherein, the inner rod 711 is made of a flexible heat-conducting material, and the support ring 712 is made of a rigid heat-conducting material.

[0053] The rigidity of the support ring 712 provides the necessary support for the push rod 71, enhancing the overall structural stability of the push rod 71. During the advancement process, especially when subjected to external forces or when precise control of the advancement direction is required, the support ring 712 prevents the push rod 71 from excessive bending or deformation, ensuring that the push rod 71 can accurately advance along the predetermined path and accurately inject the embryo into the target location.

[0054] The support ring 712, made of a rigid, heat-conducting material, closely mates with the inner rod 711, further aiding heat transfer. It distributes heat from the heater 8 more evenly across the surface of the push rod 71, allowing the phase-change connector 73 to receive more comprehensive heat, improving the uniformity and consistency of the phase change, and ensuring a smoother and more reliable separation of the push rod 71 from the piston 72.

[0055] More preferably, most of the support rings 712 do not have thermal conductivity, and only the support rings 712 near the phase change connector 73 have thermal conductivity.

[0056] Preferably, the spherical connector 74 is made of heat-insulating material.

[0057] During embryo transfer, embryos are very sensitive to temperature. When heater 8 heats propulsion rod 71 to induce phase change in phase-change connector 73, if spherical connector 74 is not made of a heat-insulating material, heat may be transferred to the embryo within flexible conduit 3 through spherical connector 74. Excessively high temperatures may damage the embryo's cellular structure and physiological functions, reducing its activity and thus affecting the success rate of embryo transfer. However, using a heat-insulating material for spherical connector 74 can effectively prevent heat transfer, providing a relatively stable low-temperature environment for the embryo, thereby protecting its activity.

[0058] The heat insulating material may be any one of ceramic material and polytetrafluoroethylene (PTFE).

[0059] In this embodiment, the flexible catheter 3 is divided into at least two sections, which are connected by a telescopic ring bag 4. The interior of the telescopic ring bag 4 is divided into at least four independent expansion and contraction spaces, each of which is supplied with air by a trachea 5. The end of the trachea 5 away from the telescopic ring bag 4 is connected to a pressing bag 6, and the pressing bag 6 is fixed to the transplant tube 1.

[0060] In practice, when the operator needs to adjust the bending direction of flexible catheter 3, they simply press the corresponding pressing bag 6. When pressurized, pressing bag 6 delivers gas through trachea 5 into the corresponding expansion and contraction space of telescopic ring bag 4, causing the expansion space to expand, thereby changing the bending direction and degree of flexible catheter 3. By combining the pressure of different pressing bags 6, flexible catheter 3 can be flexibly adjusted in three dimensions, allowing it to accurately reach the target embryo transfer location within the sheep.

[0061] In addition, an attached airway 9 is fixed to the surface of the flexible catheter 3, and the attached airway 9 and the outer surface of the flexible catheter 3 together constitute an air guide channel, and the air guide channel is connected between the corresponding trachea 5 and the telescopic ring bag 4. The cross-section of the attached airway 9 is an arc-shaped cross-section that matches the curvature of the outer wall of the flexible catheter 3.

[0062] The cross-section of the attached airway 9 is an arcuate cross-section that matches the curvature of the outer wall of the flexible catheter 3. This design ensures that the height of the attached airway 9 is sufficiently low so as not to significantly increase the outer diameter of the flexible catheter 3. During embryo transfer surgery, the flexible catheter 3 needs to pass through narrow passages within the sheep's body. If its outer diameter is too large, it will increase the difficulty of passage and may even cause damage to the sheep's tissue. The arcuate cross-section of the attached airway 9, while fulfilling its air-guiding function, minimizes the impact on the outer diameter of the flexible catheter 3, allowing the flexible catheter 3 to more easily pass through the sheep's internal passages, improving the smoothness and safety of the operation.

[0063] Please refer to Figure 6 In this embodiment, a method for embryo transplantation for sheep breeding is also provided, comprising the following steps:

[0064] S1. Establishing a push injection path: Deliver the transplant tube 1, culture medium tube 2, and flexible catheter 3 to the target location through the sheep's vagina. The flexible catheter 3 can adapt to the curvature of the reproductive tract and reduce tissue damage.

[0065] S2. Initial push injection: insert the push injection assembly 7 into the transplant tube 1, push the piston 72 through the push rod 71, and then push the embryos in the culture medium tube 2 into the flexible catheter 3.

[0066] S3. Phase change triggering: After the phase change connector 73 undergoes phase change and liquefaction, continue to push the push rod 71, and then push the embryo in the flexible catheter 3 into the sheep's uterus through the spherical connector 74. After the piston 72 is separated from the push rod 71, the spherical connector 74 directly contacts the embryonic fluid. Its spherical structure can adapt to the bending shape of the flexible catheter 3 and form a dynamic seal with the inner wall of the flexible catheter 3. In addition, the spherical connector 74 also reduces the friction resistance with the inner wall of the flexible catheter 3, and at the same time applies uniform pressure to avoid embryo damage caused by residual embryonic fluid or concentrated pressure.

[0067] S4. Withdrawal of instruments: Slowly remove the transplant tube 1, culture medium tube 2 and flexible catheter 3 to complete the embryo transplantation operation.

[0068] The above is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with this technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solutions and inventive concepts of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. An embryo transplant gun for sheep breeding, characterized in that: include: A transplant tube (1), a culture medium tube (2), and a flexible catheter (3) coaxially connected in sequence; A push injection assembly (7) slidably disposed in the transplant cylinder (1); The push injection assembly (7) comprises: A propulsion rod (71) having a predetermined stiffness; a spherical connector (74) fixedly connected to the distal end of the propulsion rod (71); a piston (72) slidably mounted on the propulsion rod (71), wherein an annular groove is provided at one end of the piston (72) away from the spherical connector (74); a phase-changing connector (73), the phase-changing connector (73) being embedded in the annular groove to achieve a controllable detachable connection between the propulsion rod (71) and the piston (72); The inner diameter D3 of the flexible catheter (3), the inner diameter D2 of the culture fluid tube (2), and the inner diameter D1 of the transplant tube (1) satisfy: D3 < D2 < D1, and the outer diameter D4 of the spherical connector (74) satisfies: D4 = D3.

2. The embryo transplant gun for sheep breeding according to claim 1, characterized in that: A heating element (8) is provided on the outside of the propulsion rod (71).

3. The embryo transplant gun for sheep breeding according to claim 1, characterized in that: The propulsion rod (71) comprises an inner rod (711), an outer fixing sleeve of the inner rod (711) is provided with a support ring (712) and an elastic ring (713), and the support ring (712) and the elastic ring (713) are distributed crosswise in sequence; The inner rod (711) is made of a flexible heat-conducting material, and the support ring (712) is made of a rigid heat-conducting material.

4. The embryo transplant gun for sheep breeding according to claim 1, characterized in that: The spherical connector (74) is made of heat-insulating material.

5. The embryo transplant gun for sheep breeding according to claim 1, characterized in that: The flexible catheter (3) is divided into at least two sections, and the two sections are connected by a telescopic ring bag (4). The interior of the telescopic ring bag (4) is divided into at least four independent expansion and contraction spaces, and each expansion and contraction space is supplied with air by a trachea (5). The end of the trachea (5) away from the telescopic ring bag (4) is connected to a pressing bag (6), and the pressing bag (6) is fixed to the transplant tube (1).

6. The embryo transplant gun for sheep breeding according to claim 1, characterized in that: An attached airway (9) is fixed to the surface of the flexible catheter (3), and the attached airway (9) and the outer surface of the flexible catheter (3) together constitute an air guide channel, and the air guide channel is connected between the corresponding trachea (5) and the telescopic ring bag (4), and the cross section of the attached airway (9) is an arc-shaped cross section that matches the curvature of the outer wall of the flexible catheter (3).

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