Method for detecting early pregnancy of sows and application of method

Abstract

The invention belongs to the technical field of livestock breeding, and particularly relates to a method for detecting early pregnancy of sows and application of the method. Specifically, the invention discloses a sow early pregnancy detection method based on a B-ultrasonic technology, which realizes high-sensitivity and high-specificity detection of the pregnancy state of a sow within 21 days after hybridization by optimizing operation means, ultrasonic parameters, image processing and judgment standards.

Description

Technical Field

[0001] This invention belongs to the field of animal husbandry and reproductive technology, and specifically relates to a method for early pregnancy detection in sows and its application. Background Technology

[0002] In recent years, with the rapid development of large-scale and intensive pig farming in my country, the scale and quality of breeding pigs have become particularly important. Against this backdrop, in the batch management of modern pig farms, the timely and accurate detection of sow pregnancy directly affects reproductive efficiency and farming profitability. With the popularization of imaging technology, pig ultrasound machines have become the standard tool for detecting sow pregnancy. However, ultrasound images are not entirely consistent at different stages of pregnancy, and the ease of interpretation also varies.

[0003] Theoretically, a gestational sac may be visible 18 days after mating, but due to significant individual differences, the image at this time is difficult to identify and unstable. Most farms recommend starting to monitor the sow's pregnancy status after day 21. At this time, a small, poorly defined dark area may appear in the ultrasound image, which is the early gestational sac. Due to its small diameter and low contrast, it remains difficult to interpret. Therefore, traditional methods for detecting sow pregnancy typically consider 25 to 35 days of gestation as the optimal time for ultrasound examination. At this stage, the gestational sac has significantly increased in size, the image contrast is clear, the fetal structure gradually becomes visible, and the accuracy of detection is significantly improved.

[0004] However, since the traditional B-ultrasound detection window for sow pregnancy is usually 25 to 35 days or even later after mating, it cannot determine the early pregnancy status of sows, resulting in a time lag. This leads to an excessively long period of ineffective feeding for non-pregnant sows, directly increasing the feeding costs of pig farms.

[0005] Accurate and convenient detection of sow pregnancy at an earlier stage has become a challenge in the livestock industry. The reasons are as follows: 1. If pregnancy is detected a week earlier (i.e., 17 days after insemination), assuming a successful pregnancy, the embryo is only 1-2 mm in diameter, its position is variable, and its acoustic reflection is weak. Routine ultrasound examinations have insufficient resolution, resulting in a misjudgment rate >40%. 2. Using other solutions, such as vaginal probes, carries the risk of animal injury and is complex, making it unsuitable for large-scale batch operations. 3. While early pregnancy can be detected through blood hormone tests, these are complex and require high-standard laboratory conditions, placing high demands on staff and incurring significant costs. Therefore, they are also unsuitable for large-scale batch production and breeding in pig farms. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention aims to propose a method for early pregnancy detection in sows and its application. By optimizing operational methods, ultrasound parameters, image processing, and judgment criteria, it solves the problem of high breeding costs caused by the time lag of existing pregnancy detection methods. It can determine the pregnancy status of sows through non-invasive means within 17 days after mating, achieving early, highly sensitive, and highly specific detection of sow pregnancy status.

[0007] Specifically, the daily comprehensive feeding cost of a sow is around 25 yuan. Detecting non-pregnant sows one day earlier after mating can save the farm 25 yuan. Traditional ultrasound detection of sow pregnancy typically occurs 25-30 days or more after mating (embryo diameter > 5mm), which introduces a time lag, leading to excessively long periods of ineffective feeding for non-pregnant sows and increased farm costs. If pregnancy is detected 7 days earlier per sow, each sow can shorten non-productive days by 16-18 days per year, saving approximately 400 yuan in feeding costs. Based on the average non-pregnant rate in sow breeding in this field, this translates to at least 600,000 yuan in savings per 10,000 sows per year. Therefore, the purpose of this invention is to standardize the procedures for sow pregnancy detection, ensuring early and accurate identification of non-pregnant sows for timely re-mating or culling, thereby improving herd reproductive efficiency, reducing non-productive days (NPD), and lowering breeding costs.

[0008] To achieve the above objectives, this invention selects a detection site different from traditional methods and combines indicators such as the area and structure of the liquid dark area in the detection site and the rate of change of uterine wall thickness to effectively and accurately determine the pregnancy status of sows 21 days or earlier after conception.

[0009] In a first aspect, the present invention provides a method for early pregnancy detection in sows, the method including a step of performing ultrasound detection on the sow, the detection time being within 21 days after mating.

[0010] Furthermore, the testing is conducted within 17 days after the sow is bred.

[0011] Furthermore, the detection site is located between the groin and the first to second nipples from the bottom in the sow.

[0012] Furthermore, the detection indicators include the presence of embryonic fluid-filled dark areas and / or the rate of change in uterine wall thickness. The rate of change in uterine wall thickness refers to the percentage increase in uterine wall thickness within 21 days post-mating compared to the non-pregnant state.

[0013] Furthermore, the condition of embryonic fluid-filled dark areas in pregnancy is defined as embryonic fluid-filled dark areas with a diameter ≥8mm and clear edges.

[0014] Furthermore, the rate of change in uterine wall thickness during pregnancy is 15%-30% higher than that in non-pregnant women.

[0015] Secondly, the present invention also provides the application of the method described in the first aspect in determining pregnancy in sows.

[0016] Furthermore, the application is to determine whether a sow is pregnant within 21 days after mating, preferably within 17 days after mating.

[0017] Furthermore, the application is in improving the sensitivity and specificity of early pregnancy assessment in sows.

[0018] In one specific embodiment of the present invention, the sensitivity of early pregnancy assessment in sows is higher than 97.0%, and the specificity is higher than 91.0%. For example, on day 17, the sensitivity of pregnancy assessment is higher than 97.1%, and the specificity is higher than 91.6%; from day 21 onwards, the sensitivity of pregnancy assessment is 100%, and the specificity is higher than 95.8%.

[0019] Thirdly, the present invention also provides an information processing method for determining pregnancy in sows, characterized in that the method is executed by a computer and includes the following steps: S1. Acquire medical data from an ultrasound detection device via a computer interface. The medical data is acquired by the method described in the first aspect and includes detection index data. The detection index data includes uterine wall thickness and diameter of the embryonic fluid-filled dark area. S2. The medical data is denoised and normalized by the processor to obtain standardized data containing detection index data; S3. The standardized data is analyzed by the processor running a program to obtain the change rate of the diameter of the embryonic fluid-filled dark area and the uterine wall thickness. After analyzing and judging the change rate of the uterine wall thickness and the diameter of the embryonic fluid-filled dark area, a conclusion is drawn regarding the sow's pregnancy. S4. The conclusion is provided via an output device.

[0020] Furthermore, in step S3, the criteria for analyzing and judging the rate of change in uterine wall thickness and the diameter of the embryonic fluid-filled dark area include at least one of the following: (1) The thickness of the uterine wall is 15%-30% thicker than in the non-pregnant state; (2) The diameter of the embryonic fluid dark area is ≥8mm and the edge is clear.

[0021] Fourthly, the present invention also provides a computer-readable storage medium containing a data processing program, which, when executed by a processor, implements the method described in the first aspect and / or the information processing method described in the third aspect.

[0022] In one specific embodiment of this application, a computer-readable storage medium is provided, the computer-readable storage medium containing a data processing program, which, when executed by a processor, can implement a method comprising the following four steps: S1. Perform ultrasound examination on the sow within 21 days after mating. The examination indicators include the rate of change in uterine wall thickness and / or the condition of the embryonic fluid-filled dark area. The examination indicator data from the ultrasound examination equipment are obtained through a computer interface. The examination indicator data includes uterine wall thickness and the diameter of the embryonic fluid-filled dark area. S2. The medical data is denoised and normalized by the processor to obtain standardized data containing detection index data; S3. The standardized data is analyzed by running a program through the processor to obtain the change rate of the diameter of the embryonic fluid dark area and the uterine wall thickness. After analyzing and judging the change rate of the uterine wall thickness and the diameter of the embryonic fluid dark area, a tendency conclusion for judging the sow's pregnancy is obtained. Further, in step S3, if the analysis and judgment of the rate of change in uterine wall thickness and the diameter of the embryonic fluid dark area meet at least one of the following conditions, then the tentative conclusion is determined to be that the sow is in early pregnancy: (1) The thickness of the uterine wall is 15%-30% thicker than in the non-pregnant state; (2) The diameter of the embryonic fluid dark area is ≥8mm and the edge is clear.

[0023] S4. The aforementioned tendency conclusion is provided through an output device.

[0024] Compared with the prior art, the present invention has the following advantages: (1) The method for early pregnancy detection in sows in this invention can significantly advance the time for pregnancy diagnosis from 25-28 days after mating to 17 days after mating, and the diagnostic accuracy is higher than 97% and the diagnostic specificity is higher than 91%.

[0025] (2) Compared with the traditional operation process, the present invention can shorten the ineffective feeding cycle by 7-10 days, which helps to accurately identify non-pregnant sows in the early stage so as to replenish or cull them in time, thereby improving the reproductive efficiency of the pig herd, reducing non-productive days and breeding costs.

[0026] (3) The present invention innovatively selects the rate of change of uterine wall thickness and the condition of embryonic fluid dark area as indicators for judging the pregnancy status of sows, and integrates them with B-ultrasound equipment and computer-readable storage medium, which is expected to realize semi-automatic or even fully automated detection and evaluation of early pregnancy in sows.

[0027] (4) The method for early pregnancy detection in sows in this invention is suitable for rapid pregnancy screening in large-scale farms. It is easy to operate and has low equipment cost. It not only lowers the operating threshold for veterinarians, but also helps in the development and use of portable equipment in the future. Attached Figure Description

[0028] Figure 1 This is a schematic diagram showing the location and angle for ultrasound examination.

[0029] Figure 2 These are ultrasound images of sows after mating. Image A shows a sow 17 days post-mating for diagnosis of pregnancy, and image B shows a sow 20 days post-mating for diagnosis of pregnancy. The gestation sac is circled in red.

[0030] Figure 3 Images of the uterine horns of sows after mating, where A is an image of the uterine horns of sows on day 8 after mating, and B is an image of the uterine horns of sows on day 14 after mating. Detailed Implementation

[0031] The following detailed embodiments further illustrate the concept and technical effects of the present invention to fully understand its purpose, features, and effects. Unless otherwise specified, all methods described are conventional methods. Unless otherwise specified, all materials are available from publicly available commercial sources. The illustrative embodiments and descriptions of the present invention are used to explain the invention and do not constitute an undue limitation thereof. It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0032] Example 1 1. The relevant information about the experimental pig farm is as follows: Pig farm location: Shimen County, Hunan Province.

[0033] Pig farm size: Number of pigs: 463 replacement sows, 6,000 breeding sows, and 65 boars.

[0034] Production mode: continuous production.

[0035] Equipment and facilities: automated material line, transfer tower, negative pressure ventilation.

[0036] Staffing: 1 technical farm manager, 2 technical supervisors, 16 technicians, 16 feeders, and 13 logistics staff, totaling 48 people.

[0037] Pig breeds: French-American + American.

[0038] 2. Testing methods and procedures 2.1 Equipment and Devices The HS-1600V veterinary ultrasound scanner (HONDA ELECTRONICS CO., LTD.) and its matching linear ultrasound system were used, and the settings recommended in the product manual and the pregnancy measurement procedures for different species were followed.

[0039] 2.2 Preparations before inspection 2.2.1 Equipment and Supplies Preparation: Ultrasound diagnostic instrument: Ensure it has sufficient power or is connected to a power source, and that the probe cable is intact; Coupling agent: Use veterinary-specific coupling agent compatible with ultrasound diagnostic instruments to facilitate ultrasound wave transmission; Cleaning supplies: paper towels and disinfectant wipes, used to wipe the probe and the sow's skin; Marking tools: spray paint, markers, etc., used to mark the pregnancy status.

[0040] 2.2.2 Use ultrasound model and parameter settings (see 2.1).

[0041] 2.2.3 Preparations before sow examination: Perform the examination in front of the gestation crate or feeding stall, allowing the sow to stand quietly and avoiding operation while the sow is struggling violently. The examination area should be clean: the abdominal and flank areas of the sow to be examined (behind the last two pairs of teats and in front of the thigh bones) should be free of excessive feces and mud.

[0042] 2.2.4 Personnel preparation: Operators should have received professional training, be familiar with the anatomical structure of sows and the interpretation of B-ultrasound images, and wear clean work clothes and water shoes.

[0043] 2.3 Ultrasound Examination Procedure Step 1: Stabilizing and Soothing Gently guide the sow to the gestation stall or keep her quiet while feeding, and gently stroke her abdomen and back to help her relax.

[0044] Step 2: Apply coupling agent Apply sufficient coupling agent to the probe surface and the skin area (abdomen and flank) of the sow to be tested, ensuring good contact between the probe and the skin without air gaps.

[0045] Step 3: Probe Placement and Scanning like Figure 1 The diagram shows the location and angle for ultrasound examination.

[0046] 2.3.1 Location: Place the probe firmly against the sow's abdomen and flank, approximately on the horizontal line between the last pair of teats and the second-to-last pair. When using traditional methods, the location is chosen between the second and third pairs of teats from the end. Disinfect and wipe the probe between different sows, especially in areas with disease risk, to prevent cross-infection.

[0047] 2.3.2 Angle: From the groin forward to the midpoint between the second and last nipples, at approximately a 45-degree angle to the spine, slightly tilted forward or backward to find the best image. When using the traditional method, the position is chosen between the second and third pairs of nipples from the bottom, at a 45-degree angle upward towards the pelvic inlet.

[0048] 2.3.3 Technique: Gently and steadily press the skin and make small fan-shaped movements to systematically scan the uterine area.

[0049] 2.3.4 Magnify and observe the suspected pregnancy area in the uterine horn, and record the characteristics of the fluid-filled dark area.

[0050] 2.3.5 Measure the diameter of the dark area and the thickness of the uterine wall, compare with the judgment criteria, confirm the pregnancy status, assess the sow's pregnancy condition, and adjust feeding and management strategies accordingly. When using traditional methods for examination, the thickness of the uterine wall cannot be clearly observed due to the location of the examination.

[0051] Table 1. Comparison of key points between Example 1 and traditional detection methods

[0052] Step 4: Image Interpretation Positive pregnancy (+): 17-21 days after mating: Multiple black, round or tadpole-shaped gestational sacs (anechoic dark areas) appear on the screen, with a diameter of ≥8mm and clear edges; the uterine wall is 15%-30% thicker than in the non-pregnant state.

[0053] like Figure 2 The image shown is a pregnancy monitoring chart of a sow after weight-bearing. Figure 2 Image A shows a diagnosis of pregnancy in a sow 17 days after mating. Figure 2 Image B shows a diagnosis of pregnancy in a sow 20 days after mating. The gestational sac is circled in red.

[0054] like Figure 3 The image shown is of the uterine horn of a sow after weight-bearing. Figure 3 Image A shows the uterine horn of the sow on the 8th day after mating. Figure 3 Image B shows the uterine horn of the sow on day 14 post-mating. It can be seen that the uterine horn outline was clear in the early stages, with consistent echoes inside. On day 14, the uterine horn outline became blurred, the echoes inside were inconsistent, and a fluid-filled dark area appeared.

[0055] 25 days or more after mating: White fetal skeletal images (strong echogenic spots) can be seen within the gestational sac, and even fetal heartbeats (flickering spots) can be seen. This is conclusive evidence of pregnancy.

[0056] Negative pregnancy (-) / Open pregnancy: The screen image is uniform, gray or snowflake-like, with no obvious gestational sac or fetal structure. The bladder may appear as a large, regular black circle; careful differentiation is necessary.

[0057] Step 5: Recording and Tagging Immediate marking: Clearly mark the sow's back with spray paint.

[0058] "+" or "pregnant" or green mark: Positive pregnancy.

[0059] "-" or "empty" or red mark: Negative pregnancy.

[0060] A question mark or a yellow marker indicates a suspicious condition requiring re-examination.

[0061] Detailed records: Register the test results in the pig farm management software or on the record card, including: sow ear tag, test date, test result, and operator's name. For non-pregnant sows, record their return to estrus behavior to arrange for re-examination or culling.

[0062] Step Six: Equipment Cleaning and Storage After the test is completed, wipe the coupling agent and dirt off the probe and instrument with a paper towel.

[0063] Disinfect the probe by gently wiping it with a disinfectant wipe (avoid using strong corrosive disinfectants).

[0064] Store the ultrasound machine properly in a dry and safe place.

[0065] 2.4 Testing Groups, Testing Schedule, and Statistics of Testing Results For each batch of experiments, 60 healthy, reproductively healthy three-way crossbred gilts weighing 130-150 kg were selected and randomly divided into a traditional method testing group and a new method testing group, with 30 gilts in each group. A total of 10 batches of experiments were conducted, and the experimental data were finally summarized. Before the experiment, ultrasound imaging was performed on the ovaries and uterine horns of the test subjects, and the data were recorded as initial data.

[0066] Subsequently, starting on any day of the estrus cycle of sows in the same batch, boars were used to induce estrus in the morning and afternoon each day. The estrus status of the sows was recorded, and artificial insemination was performed. Pregnancy and conception status of the sows were detected using ultrasound on days 18, 21, 25, and 28 after insemination. The actual farrowing numbers of sows with conception were recorded around day 114 (for sows with normal pregnancies but failed farrowing, these were still counted as actual pregnancies). The number of pregnancies detected in sows was recorded for different groups and on different testing dates. False positives and false negatives were calculated based on the final actual conception and farrowing data to determine the actual detection rate, specificity, and sensitivity of the two testing methods. The data are summarized below: Table 2 Comparison of detection results data between Example 1 and traditional methods

[0067] As shown in Table 2, compared with the traditional B-ultrasound pregnancy examination protocol, the pregnancy examination during days 17 to 21 has significantly better sensitivity and specificity, thus meeting the needs of early pregnancy examination in sows.

[0068] The embodiments described above are only some embodiments of the present invention, not all embodiments. Other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are all within the scope of protection of the present invention.

Claims

1. A method for early pregnancy detection in sows, characterized in that, The method includes a step of performing ultrasound examination on the sow, which is conducted within 21 days after mating, and the examination indicators include the rate of change in uterine wall thickness and / or the presence of embryonic fluid dark areas.

2. The method according to claim 1, characterized in that, The testing was conducted within 17 days after the sow was bred.

3. The method according to claim 1, characterized in that, The detection site is located between the groin and the first to second teats from the bottom in the sow.

4. The method according to claim 1, characterized in that, The rate of change in uterine wall thickness during pregnancy is 15%-30% higher than that in non-pregnant women.

5. The method according to claim 4, characterized in that, The condition of embryonic fluid-filled dark areas in pregnancy is defined as those with a diameter ≥8mm and clear edges.

6. The application of the method according to any one of claims 1-5 in the early pregnancy determination of sows, wherein the application is to determine the pregnancy status of sows within 21 days after mating, preferably within 17 days after mating.

7. The application according to claim 6, characterized in that, The application is for improving the sensitivity and specificity of early pregnancy assessment in sows; preferably, the sensitivity of early pregnancy assessment in sows is higher than 97.0%, and the specificity is higher than 91.0%.

8. An information processing method for determining pregnancy in sows, characterized in that, The method is executed by a computer and includes the following steps: S1. Acquire medical data from an ultrasound detection device via a computer interface, wherein the medical data is acquired by the method described in any one of claims 1-5 and includes detection index data; the detection index data includes uterine wall thickness and diameter of the embryonic fluid-filled dark area. S2. The medical data is denoised and normalized by the processor to obtain standardized data containing detection index data; S3. The standardized data is analyzed by running a program through a processor to obtain the change rate of the diameter of the embryonic fluid-filled dark area and the uterine wall thickness. After analyzing and judging the change rate of the uterine wall thickness and the diameter of the embryonic fluid-filled dark area, a tendency conclusion for judging the sow's pregnancy is obtained; and S4. The aforementioned tendency conclusion is provided through an output device.

9. The information processing method according to claim 8, characterized in that, In step S3, if the analysis and judgment of the rate of change in uterine wall thickness and the diameter of the embryonic fluid dark area meet at least one of the following conditions, then the tentative conclusion is determined to be that the sow is in early pregnancy: (1) The thickness of the uterine wall is 15%-30% thicker than in the non-pregnant state; (2) The diameter of the embryonic fluid dark area is ≥8mm and the edge is clear.

10. A computer-readable storage medium comprising a data processing program that, when executed by a processor, implements the method as claimed in any one of claims 1-5 and / or the information processing method as claimed in claim 8 or 9.

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