Ruminant methane emission measuring system and method based on milking robot

Abstract

The invention relates to a ruminant methane emission measuring system and method based on a milking robot, and the ruminant methane emission measuring system comprises a gas collection device which is arranged in a feeding trough area of the milking robot and is used for collecting sample gas in real time during the feeding period of ruminants, and the sample gas comprises animal exhaled gas; the gas analysis unit is connected with the gas collection device and is used for synchronously analyzing the concentration of methane and the concentration of carbon dioxide in the sample gas; and the data recording and processing unit is in communication connection with the gas analysis unit and is used for recording gas concentration data and detection time and calculating the daily methane emission amount based on the concentration data and the physiological parameters of the ruminant. According to the method, the milking window of the milking robot is used for measuring the methane emission amount of the dairy cow at the individual level for the first time, the balance of individual measurement record numbers is guaranteed, and automatic, high-throughput, large-scale and continuous monitoring is achieved.

Description

Technical Field

[0001] This invention relates to the field of agricultural environmental monitoring technology, specifically to a system and method for measuring methane emissions from ruminants based on a milking robot. Background Technology

[0002] Methane is the second largest greenhouse gas after carbon dioxide, with a global warming potential of 28-34 times that of carbon dioxide on a centennial timescale. Global livestock farming contributes approximately 14-25% of anthropogenic methane emissions, primarily from methane produced by ruminant animals (such as cattle and sheep) through intestinal fermentation during digestion. Within the livestock industry, dairy cows account for the highest proportion of total methane emissions. Therefore, accurately quantifying methane emissions from dairy cows is crucial for assessing the carbon footprint of livestock farming, developing scientific emission reduction strategies, and conducting genetic selection for methane emission traits.

[0003] Currently, the mainstream methods for measuring methane emissions in ruminants mainly include the respiratory metabolism chamber method, the sulfur hexafluoride tracer method, and the sniffing method.

[0004] One method, the respiratory metabolism chamber method, involves confining animals to a sealed chamber for extended periods and calculating their total gas emissions by precisely measuring the flow rate and composition changes of incoming and outgoing gases. While the data is accurate, the construction and operating costs are extremely high (typically hundreds of thousands of dollars), the measurement throughput is very low (only one or a few animals can be measured at a time), and isolating the animals from their normal social environment and feeding conditions can induce stress responses and alter their natural behaviors (such as feeding and rumination), leading to discrepancies between the measured data and their emissions in a real pasture environment. Therefore, this method is difficult to apply to routine monitoring in large-scale commercial ranches.

[0005] Sulfur hexafluoride (SF6) tracer method is a semi-field measurement technique. Its principle involves inserting a permeation tube that releases SF6 gas at a constant rate into the rumen of an animal. SF6, along with methane produced in the rumen, is expelled with belching. A small amount of exhaled gas is collected by wearing a sampling device around the animal's neck, and the concentration ratio of SF6 and methane is analyzed using gas chromatography. Combined with the known SF6 release rate, the methane emission rate is calculated. This method allows animals to move in a relatively natural environment, is less expensive than a respiratory metabolism chamber, and allows for continuous measurements for several days. However, the insertion of the permeation tube requires professional veterinary intervention, posing animal health risks; the sampling tubing is complex and easily damaged in a pasture environment; SF6 itself is an extremely potent greenhouse gas (with a global warming potential 23,500 times that of CO2), and any leakage would cause severe environmental impacts; furthermore, its measurement accuracy is affected by the rumen environment (temperature, pH), and may fluctuate.

[0006] A representative device for the sniffing method is the GreenFeed system. This system acts as a standalone feeding station; when animals actively access and consume small amounts of feed, a fume extraction hood above the system collects the exhaled gases from their mouths and noses and performs real-time compositional analysis. This method causes minimal disturbance to the animals and provides individual data. However, its data acquisition relies entirely on the animals' "voluntary access." This leads to significant differences in sampling frequency among individuals within the group (dominant cattle access the system frequently, while weaker cattle have sparse data) and uneven distribution of sampling time points (the timing of measurements cannot be controlled), thus introducing serious sampling bias and making group-level emission assessments and fair comparisons between individuals difficult.

[0007] Therefore, there is an urgent need at the ranch level for a technical solution that can be seamlessly integrated into daily management processes and can perform regular and standardized individual measurements on large-scale cattle herds. Summary of the Invention

[0008] In view of the shortcomings of the prior art, the main objective of the present invention is to provide a system and method for measuring methane emissions from ruminants based on a milking robot, so as to solve the above-mentioned problems.

[0009] The technical solution of the present invention is as follows:

[0010] This invention proposes a methane emission measurement system for ruminants based on a milking robot, comprising:

[0011] A gas collection device is installed in the feeding trough area of ​​the milking robot to collect sample gas in real time during feeding of ruminants, the sample gas including the gas exhaled by the animals.

[0012] A gas analysis unit, connected to the gas collection device, is used to simultaneously analyze the methane and carbon dioxide concentrations in the sample gas;

[0013] A data recording and processing unit, which is communicatively connected to the gas analysis unit, is used to record gas concentration data and detection time, and to calculate daily methane emissions based on the concentration data and physiological parameters of ruminants.

[0014] In some embodiments, the gas collection device comprises the following sequentially connected components:

[0015] The sampling probe is placed in the feeding trough area of ​​the milking robot to guide the sample gas;

[0016] A gas drying device, connected to the sampling probe via a conduit, is used to remove water vapor from the sample gas;

[0017] The filter, with one end connected to the gas drying device via a conduit and the other end connected to the gas analysis unit via a conduit, is used to filter out particulate matter in the sample gas.

[0018] In some embodiments, the filter includes a first filter and a second filter, wherein one end of the first filter is connected to the gas drying device via a conduit, and the other end is connected to one end of the second filter via a conduit, and the other end of the second filter is connected to the gas analysis unit.

[0019] In some embodiments, the gas analysis unit includes two infrared spectrometers, both of which are connected to the filter. One infrared spectrometer is used to determine the methane concentration, and the other infrared spectrometer is used to determine the carbon dioxide concentration.

[0020] In some embodiments, the step of the data recording and processing unit calculating daily methane emissions includes:

[0021] Obtain the concentrations of methane and carbon dioxide, and calculate the concentration ratio of methane to carbon dioxide;

[0022] Daily carbon dioxide emissions are calculated using a model based on individual information of ruminants.

[0023] Daily methane emissions are calculated based on the concentration ratio of methane to carbon dioxide and the daily emissions of carbon dioxide.

[0024] In some embodiments, the formula for calculating the concentration ratio of methane and carbon dioxide is:

[0025] C CH4 :C CO2 =MeC:CO2C;

[0026] Among them, C CH4 C represents the actual concentration of methane gas emitted by ruminants. CO2 The values ​​represent the actual carbon dioxide concentration emitted by ruminants, MeC represents the average methane concentration measured each time, and CO2C represents the average carbon dioxide concentration measured each time.

[0027] In some embodiments, the formula for calculating daily methane emissions is:

[0028] M CH4 =M CO2 ×((C CH4 ×Mr CH4 ) / 22.4):((C CO2 ×Mr CO2 ) / 22.4);

[0029] Among them, M CH4M represents daily methane emissions. CO2 For daily carbon dioxide emissions, C CH4 C represents the actual concentration of methane gas emitted by ruminants. CO2 Mr represents the actual carbon dioxide concentration emitted by ruminants. CH4 Mr represents the molecular weight of methane. CO2 is the molecular weight of carbon dioxide.

[0030] The present invention also proposes a method for measuring methane emissions from ruminants based on the above-mentioned methane emission measurement system for ruminants, comprising the following steps:

[0031] The gas collection and analysis process is automatically initiated when ruminants are being milked and fed inside the milking robot.

[0032] Simultaneous measurement of methane and carbon dioxide concentrations was performed on the collected sample gas.

[0033] Identify and filter valid concentration measurement records;

[0034] Based on the effective concentration data after screening and the physiological parameters of the animals, the daily methane emissions of an individual were calculated.

[0035] In some embodiments, identifying and screening valid concentration measurement records includes:

[0036] (1) Data preprocessing: Obtain all raw concentration data during the milking period;

[0037] (2) Belching event identification: Calculate the background value of ambient methane concentration during the measurement period; set a belching peak detection threshold; scan the methane concentration sequence to find significant peaks exceeding the threshold;

[0038] (3) Identification of respiratory validity period: Calculate the 25th percentile of all carbon dioxide concentration data during the measurement period; remove the interval in the carbon dioxide concentration sequence where the carbon dioxide concentration is below the 25th percentile for a continuous period of time, which is the respiratory validity period;

[0039] (4) Validity determination: If at least one valid belching peak is identified within the same measurement period and there is at least one valid period of carbon dioxide that meets the requirements, then all or part of the concentration data recorded during the milking process shall be marked as "valid record" and the average concentration of methane and carbon dioxide shall be calculated for subsequent calculations.

[0040] In some embodiments, the method further includes the step of: binding the calculated individual methane emission data with individual identification information and transmitting it to the ranch management system for the purpose of analyzing the group emission level, screening individuals with extremely low or extremely high emissions, breeding of emission traits, or optimizing feeding management strategies.

[0041] The advantages of this invention compared to existing technologies are as follows: This invention proposes a methane emission measurement system for ruminants based on a milking robot. This system is the first to utilize the milking window of the milking robot to measure methane concentration, and the entire system achieves automated operation. While the ruminants are being milked and feeding inside the milking robot, the gas collection and analysis process is automatically initiated, requiring minimal manual intervention, greatly improving measurement efficiency, reducing errors caused by human factors, and saving labor costs. Specifically, it has at least the following practical effects:

[0042] In this invention, the sampling probe in the gas collection device is fixed to the feeding trough of the milking robot, ensuring stable guidance of the sample gas. The gas drying device removes water vapor from the sample gas, preventing it from interfering with subsequent analysis, such as avoiding condensation in the analytical instrument that could affect measurement accuracy. The polytetrafluoroethylene (PTFE) filter efficiently removes particulate matter from the sample gas, reducing wear and interference from particulate matter on the analytical unit, ensuring the accuracy of analytical results and extending the instrument's lifespan. This sequential connection design allows the sample gas to be processed promptly and effectively after collection, ensuring that the gas quality entering the gas analysis unit meets requirements.

[0043] In this invention, the gas analysis unit employs two infrared spectrometers, which can be readily connected to the gas acquisition device to simultaneously analyze the concentrations of methane and carbon dioxide in the sample gas. Infrared spectroscopy technology features high sensitivity and selectivity, enabling rapid and accurate measurement of the concentrations of the two gases. This avoids errors and time differences that may result from multiple measurements, thus improving measurement efficiency and the reliability of the analysis results.

[0044] In this invention, the data recording and processing unit is communicatively connected to the gas analysis unit, enabling detailed recording of gas concentration data and detection time. This data not only provides a basis for current methane emission measurements but also forms a long-term data record, facilitating the tracking and analysis of methane emissions from ruminants to understand their emission patterns and trends.

[0045] This invention cleverly utilizes the milking activity that ruminants must perform 2-3 times a day as a fixed measurement window, embedding the monitoring system into the milking robot to achieve "monitoring during production." It causes no additional interference to the cows, ensuring natural animal behavior and high data ecological validity.

[0046] The spontaneous milking process of this invention ensures that every individual in the group can be measured regularly and with equal probability, completely solving the sampling bias problem caused by the voluntary access of animals in the traditional sniffing method, and laying the foundation for accurate assessment at the group level and fair comparison between individuals.

[0047] This invention achieves a reliable conversion from "concentration" to "flux" by combining instantaneous concentration measurement with theoretical CO2 emissions based on energy metabolism. This method significantly improves the accuracy of the final daily methane emission estimate while retaining measurement convenience.

[0048] This invention's system is based on a mature milking robot platform with expanded functionality and low marginal cost. It utilizes existing infrared spectroscopy analysis technology, avoiding the consumables and complex operations of SF6 tracer methods, as well as the huge infrastructure investment required for respiratory and metabolic chambers, making widespread application in large-scale commercial dairy farms possible.

[0049] It should be understood that the description in the Summary of the Invention is not intended to limit the key or essential features of the embodiments of the present invention, nor is it intended to restrict the scope of the invention. Other features of the invention will become readily apparent from the following description. Furthermore, implementation of any embodiment of the present invention does not imply the simultaneous possession or achievement of multiple or all of the aforementioned beneficial effects. Attached Figure Description

[0050] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0051] The structures, proportions, sizes, etc. illustrated in this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed herein, and are not intended to limit the conditions under which the present invention can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and objectives that the present invention can produce, should still fall within the scope of the technical content disclosed in the present invention.

[0052] Figure 1 This is a schematic diagram of the overall structure of a ruminant methane emission measurement system based on a milking robot, according to some embodiments of the present invention.

[0053] Figure 2 This is a partially enlarged schematic diagram of the sampling probe arrangement in some embodiments of the present invention;

[0054] Figure 3 This is a flowchart illustrating a method for measuring methane emissions from ruminants according to some embodiments of the present invention.

[0055] Marked in the image:

[0056] 100-Milkming Robot;

[0057] 1-Sampling probe;

[0058] 2-Gas drying device;

[0059] 3-Filter; 301-First filter; 302-Second filter;

[0060] 4-Gas analysis unit; 401-Infrared spectrometer;

[0061] 5-Data recording and processing unit;

[0062] 6-Feeding trough;

[0063] 7-Catheter.

[0064] The same or corresponding marks in the diagram indicate the same or corresponding parts. Detailed Implementation

[0065] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. Here, the illustrative embodiments and descriptions of the present invention are used to explain the present invention, but are not intended to limit the present invention.

[0066] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0067] It should be understood that the terms "comprising / including," "consisting of," or any other variations are intended to cover non-exclusive inclusion, such that a product, apparatus, process, or method that comprises a list of elements includes not only those elements but may also include, where necessary, other elements not expressly listed, or elements inherent to such a product, apparatus, process, or method. Without further limitation, an element defined by the phrases "comprising / including," "consisting of," does not exclude the presence of additional identical elements in the product, apparatus, process, or method that includes said element.

[0068] It should also be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device, component or structure referred to must have a specific orientation, be constructed or operated in a specific orientation, and should not be construed as a limitation of the present invention.

[0069] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0070] The implementation of the present invention will be described in detail below with reference to preferred embodiments.

[0071] This invention proposes a methane emission measurement system for ruminants based on a milking robot 100, comprising a gas collection device, a gas analysis unit 4, and a data recording and processing unit 5. This system is the first to utilize the milking window of the milking robot 100 to measure methane emissions, achieving automated operation of the entire ruminant methane emission measurement system based on the milking robot 100. When ruminants are milking and feeding inside the milking robot 100, the gas collection and analysis process is automatically initiated, requiring minimal manual intervention, greatly improving measurement efficiency, reducing errors caused by human factors, and saving labor costs.

[0072] like Figure 1 As shown, the gas collection device is installed in the feeding trough 6 area of ​​the milking robot 100 (the outline of the frame other than the milking robot is shown) to collect sample gas containing the animal's exhaled gas in real time during feeding of ruminants.

[0073] In some embodiments, see continue to see Figure 2 The gas sampling device, as a key front-end component of the entire ruminant methane emission measurement system, undertakes the important task of accurately collecting and pre-processing sample gases. It consists of a sampling probe 1, a gas drying device 2, and a filter 3 connected in sequence, forming an efficient and stable collection and processing chain.

[0074] The sampling probe 1 is securely fixed to the feeding trough 6 of the milking robot 100. This ingenious positioning design allows for timely and accurate guidance of sample gas into subsequent processing during the specific and stable behavior of ruminants feeding.

[0075] Structurally, in one embodiment, the gas collection device begins with a sampling probe 1 fixed to the side wall or above the feeding trough 6. This probe is carefully crafted from a flexible plastic tube, a material that not only offers good flexibility and durability but also minimizes disturbance to animal activity. A polyethylene filter head is fitted to the end of the probe—a remarkably ingenious design detail. The polyethylene filter head consists of resin and a sintered PE filter element. This element is corrosion-resistant, dense, non-toxic, and odorless, effectively filtering large particles such as feed dust. Like a highly efficient sieve, it blocks impurities that might affect subsequent analysis, ensuring the relative purity of the gas entering the pipeline.

[0076] The sampling probe 1 is connected to the gas drying device 2 and the filter 3 in sequence via a conduit 7, such as a plastic hose with an inner diameter of 5 mm and an outer diameter of 8 mm. This type of plastic hose ensures smooth gas flow while also possessing sufficient strength and stability to adapt to the complex environment of the ranch.

[0077] The gas drying device 2 plays a crucial role in the entire data acquisition and processing process. It typically employs either a condenser or a semi-permeable membrane dryer, each with its own advantages. A condenser condenses water vapor into liquid water by lowering the temperature, thus achieving drying. A semi-permeable membrane dryer utilizes the selective permeability of the membrane, allowing only gas to pass through while blocking water vapor, lowering the dew point of the sample gas below the analyzer's requirements. This step is extremely critical because water vapor not only interferes with the accuracy of optical measurements but can also corrode the analyzer's components, affecting its lifespan and measurement accuracy.

[0078] Filter 3, as the last line of defense for the gas collection device, utilizes its excellent chemical stability and hydrophobicity to perform filtration.

[0079] See also Figure 1 The filter 3 includes a first filter 301 and a second filter 302. One end of the first filter 301 is connected to the gas drying device 2 via a conduit 7, and the other end is connected to one end of the second filter 302 via a conduit 7. The other end of the second filter 302 is connected to the gas analysis unit 4.

[0080] In some embodiments, the first filter 301 is preferably a vacuum filter. The second filter 302 is preferably a polytetrafluoroethylene (PTFE) filter.

[0081] In this invention, the first filter 301 is used for preliminary filtration, filtering particles in the air with a diameter between 10 and 100 micrometers to prevent larger particles from directly clogging the PTFE filter and extending its service life. The second filter 302 is used to prevent smaller particles from directly entering the gas analysis unit 4 (infrared spectrometer), filtering particles with a diameter between 0.5 and 10 micrometers. Since the infrared spectrometer is equipped with an internal air pump, blockage will create high negative pressure inside the instrument, causing damage to the air pump or preventing it from properly drawing gas, and ultimately damaging the infrared spectrometer.

[0082] Gas analysis unit 4, as the core analysis module of the entire ruminant methane emission measurement system, is closely connected with the aforementioned carefully designed gas collection device. It undertakes the important mission of accurately and synchronously analyzing key components in the sample gas, specifically focusing on the measurement of two key indicators: methane concentration and carbon dioxide concentration in the sample gas.

[0083] In some embodiments, see continue to see Figure 1 The gas analysis unit 4 includes two infrared spectrometers 401 arranged side by side. Both infrared spectrometers 401 are connected to the filter 3. One infrared spectrometer 401 is used to measure the methane concentration, and the other infrared spectrometer 401 is used to measure the carbon dioxide concentration.

[0084] Specifically, each of the two infrared spectrometers 401 has a second filter 302 connected to its bottom, and both second filters 302 are connected to a first filter 301 through a conduit 6.

[0085] In this invention, two Guardian NG CH4 and CO2 analyzers are preferentially used to simultaneously detect methane and carbon dioxide. The CH4 analyzer has a measurement range of 0-10000ppm, an accuracy of ±2%, a resolution of 0.01%, a response time of 30s, and an output signal of 4-20mA. The CO2 analyzer has a measurement range of 0-50000ppm, an accuracy of ±2%, a resolution of 0.01%, a response time of 30s, and an output signal of 4-20mA. This effectively improves the analysis efficiency and reduces errors caused by multiple sampling and analysis.

[0086] The data recording and processing unit 5 is connected to the gas analysis unit 4 to record gas concentration data and detection time, and to calculate the daily methane emissions based on the concentration data and the physiological parameters of ruminants.

[0087] In this invention, the data recording and processing unit 5 can be an industrial-grade embedded computer or a high-performance PLC. It connects to an infrared spectrometer via an analog or digital interface, receiving and storing gas concentration data in real time, while simultaneously recording the timestamp corresponding to each data point. This unit is pre-installed with an effective recording and recognition algorithm and a methane emission calculation program.

[0088] In some embodiments, the step of the data recording and processing unit 5 calculating daily methane emissions includes:

[0089] Obtain the concentrations of methane and carbon dioxide, and calculate the concentration ratio of methane to carbon dioxide;

[0090] Daily carbon dioxide emissions are calculated using existing models based on at least one of the following: body weight, milk yield, milk composition, and gestation days of ruminants.

[0091] Daily methane emissions are calculated based on the concentration ratio of methane to carbon dioxide and the daily emissions of carbon dioxide.

[0092] In some embodiments, the formula for calculating the concentration ratio of methane and carbon dioxide is:

[0093] C CH4 :C CO2 =MeC:CO2C;

[0094] Among them, C CH4 C represents the actual concentration of methane gas emitted by ruminants. CO2 The values ​​represent the actual carbon dioxide concentration emitted by ruminants, MeC represents the average methane concentration measured each time, and CO2C represents the average carbon dioxide concentration measured each time.

[0095] In this invention, the daily carbon dioxide emissions are calculated indirectly using a mature energy metabolism model, based on individual information of ruminants (such as weight, milk yield, milk composition, and gestation days). This is not a direct measurement, but rather a calculation based on individual information of ruminants (such as weight, milk yield, milk composition, and gestation days).

[0096] For example, heat production models, or more complex models specific to particular ruminants, can be used. These models link the energy required for an animal's maintenance, milk production, and pregnancy with carbon dioxide production. The calculation formula is typically:

[0097] M CO2 = (Maintenance energy + Milk production energy + Pregnancy energy) × Conversion coefficient

[0098] All energy requirements can be estimated from the aforementioned physiological parameters. CO2 The unit is grams per day or liters per day.

[0099] In some embodiments, the formula for calculating daily methane emissions is:

[0100] M CH4 =M CO2 ×((C CH4 ×Mr CH4 ) / 22.4):((C CO2 ×Mr CO2 ) / 22.4);

[0101] This formula can be converted to:

[0102] M CH4 =M CO2 × ;

[0103] Among them, M CH4 M represents daily methane emissions. CO2 For daily carbon dioxide emissions, C CH4 C represents the actual concentration of methane gas emitted by ruminants. CO2 Mr represents the actual carbon dioxide concentration emitted by ruminants. CH4 The molecular weight of methane is 16 g / mol. CO2 is the molecular weight of carbon dioxide, which is 44 g / mol, and 22.4 is the molar volume of an ideal gas under standard conditions.

[0104] This invention achieves a reliable conversion from "concentration" to "flux" by combining instantaneous concentration measurement with theoretical CO2 emissions based on energy metabolism. This method significantly improves the accuracy of the final daily methane emission estimate while retaining measurement convenience.

[0105] This invention also proposes a method for measuring methane emissions from ruminants using the aforementioned ruminant methane emission measurement system, such as... Figure 3 As shown, it includes the following steps:

[0106] S101: When ruminants are being milked and fed inside the milking robot, the gas collection and analysis process is automatically initiated.

[0107] S102: Simultaneous measurement of methane and carbon dioxide concentrations in the collected sample gas;

[0108] S103: Identify and screen valid concentration measurement records;

[0109] S104: Based on the effective concentration data after screening and the physiological parameters of the animals, the daily methane emissions of an individual were calculated.

[0110] In some embodiments, in S103, identifying and screening valid concentration measurement records includes: identifying belching peaks by analyzing methane concentration sequences and identifying animal respiration validity periods by analyzing carbon dioxide concentration sequences, and determining records that simultaneously meet both conditions as valid.

[0111] In one specific embodiment, taking a dairy cow as an example, after a dairy cow enters the milking robot and begins to feed, the identification and screening of valid concentration measurement records includes the following:

[0112] (1) Data preprocessing

[0113] The system first acquires all raw concentration data for the current milking period (e.g., from the start of milking cup application to the removal of the cup).

[0114] (2) Belching event identification

[0115] Calculate the background value of environmental methane concentration during this measurement period (e.g., take the 5th percentile of the lowest concentration).

[0116] Set a threshold for detecting belching peaks, for example: ambient background value + 200 ppm;

[0117] Scan the methane concentration sequence to find significant peaks exceeding this threshold. A valid belching event typically manifests as a pulse waveform that rises rapidly and then falls slowly.

[0118] (3) Identification of the expiration date of respirator

[0119] Calculate the 25th percentile (Q1) of all carbon dioxide concentration data during this measurement period;

[0120] In the carbon dioxide concentration sequence, look for intervals where the carbon dioxide concentration is consistently below Q1 for a continuous period (e.g., at least 10 seconds). This typically represents the time when the cow's head has left the measuring end, and this period should be excluded from the measurement to determine the effective breathing time.

[0121] (4) Validity determination

[0122] Only when the system identifies at least one valid belching peak within the same measurement period, and at least one valid period of carbon dioxide exists, will all or part of the concentration data recorded during that milking process (data within the valid period) be marked as "valid records," and the average concentrations of methane and carbon dioxide (C₂) be calculated. CH4 and C CO2 This information is used for subsequent calculations. Records that fail to meet the conditions will be discarded or marked as pending verification.

[0123] In some embodiments, the method further includes step S105:

[0124] The calculated individual methane emission data is linked to individual identification information and transmitted to the ranch management system for use in analyzing group emission levels, screening individuals with extremely low or high emissions, breeding of individuals with methane emission traits, or optimizing feeding and management strategies.

[0125] In one specific embodiment, the complete workflow and data application of the dairy cow methane emission measurement system based on the milking robot 100 in a dairy farm include:

[0126] The RFID ear tags worn by the cows are automatically identified when they enter the milking robot 100, and the system binds the individual's ID to the gas measurement data that will begin soon.

[0127] Milking and measurement are carried out simultaneously.

[0128] First, a gas sample containing the animal's exhaled gas is collected using a gas collection device. Then, a gas analysis unit is used to simultaneously analyze the methane and carbon dioxide concentrations in the sample gas. The entire process is fully automated and requires no human intervention.

[0129] After a single milking session, the data recording and processing unit 5 performs preliminary data processing or transmits the raw data / preliminary results to the central server of the ranch via a wireless network.

[0130] On the server side, valid record identification and daily methane emission calculation are completed. Typically, the average of multiple valid measurements taken from a cow within a day is used as its estimated daily emissions to improve accuracy.

[0131] Ultimately, the individual's methane emission data is stored in a database and integrated with the cow's other production performance and health records;

[0132] Ranch managers can use the software platform:

[0133] View group and individual methane emission reports;

[0134] Genetic evaluation: Methane emissions are used as a trait to calculate breeding value, providing a scientific basis for selecting low-emission individuals;

[0135] Evaluate feeding strategies: Compare the effects of different feed formulations or additives on average methane emissions from the population.

[0136] In this invention, the high-quality, individualized, time-series methane emission data generated by this method can be directly used for genetic breeding (screening for low-carbon emission breeding cattle), precision feeding (evaluating the emission reduction effects of different diet formulations), and carbon footprint accounting (providing accurate carbon emission data for ranches), thus promoting the green and low-carbon transformation of animal husbandry.

[0137] This invention cleverly utilizes the milking activity that ruminants must perform 2-3 times a day as a fixed measurement window, embedding the monitoring system into the milking robot to achieve "monitoring during production." It causes no additional interference to the cows, ensuring natural animal behavior and high data ecological validity.

[0138] This system is based on a mature milking robot platform with expanded functionality and low marginal cost. It utilizes existing infrared spectroscopy analysis technology, avoiding the consumables and complex operations of SF6 tracer methods, as well as the huge infrastructure investment required for respiratory and metabolic chambers, making widespread application in large-scale commercial dairy farms possible.

[0139] It will be readily understood by those skilled in the art that, without conflict, the above-mentioned preferred solutions can be freely combined and superimposed.

[0140] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A ruminant methane emission measurement system based on a milking robot, characterized in that, The application relates to a device for real-time monitoring of methane emission of ruminants, comprising: a gas collection device arranged in the feed trough area of a milking robot for collecting sample gas containing animal exhaled gas during feeding of the ruminant; a gas analysis unit connected with the gas collection device for synchronously analyzing methane concentration and carbon dioxide concentration in the sample gas; a data recording and processing unit in communication connection with the gas analysis unit for recording gas concentration data, detection time, and calculating daily methane emission based on the concentration data and physiological parameters of the ruminant.

2. The ruminant methane emission measurement system of claim 1, wherein, The gas collection device comprises sequentially connected: a sampling probe arranged in the feed trough area of the milking robot for guiding sample gas; a gas drying device connected with the sampling probe through a pipeline for removing water vapor in the sample gas; a filter having one end connected with the gas device through a pipeline and the other end connected with the gas analysis unit through a pipeline for filtering particulate matters in the sample gas.

3. The ruminant methane emission measurement system of claim 2, wherein, The filter comprises a first filter and a second filter, wherein the first filter has one end in communication with the gas drying device through a pipeline and the other end in communication with one end of the second filter through a pipeline, and the other end of the second filter is connected to the gas analysis unit.

4. The ruminant methane emission measurement system of claim 2, wherein, The gas analysis unit comprises two infrared spectrum analyzers, both of which are connected with the filter, wherein one of the infrared spectrum analyzers is used for determining methane concentration, and the other infrared spectrum analyzer is used for determining carbon dioxide concentration.

5. The ruminant methane emission measurement system of claim 1, wherein, The steps for calculating daily methane emission by the data recording and processing unit comprise: obtaining methane concentration and carbon dioxide concentration, and calculating the concentration ratio of methane and carbon dioxide; calculating daily carbon dioxide emission based on individual information of the ruminant through a model; calculating daily methane emission according to the concentration ratio of methane and carbon dioxide and the daily carbon dioxide emission.

6. The ruminant methane emission measurement system of claim 5, wherein, The formula for calculating the concentration ratio of methane and carbon dioxide is: C CH4 :C CO2 =MeC:CO2C; where C CH4 is the concentration of methane gas actually emitted by the ruminant animal, C CO2 is the concentration of carbon dioxide actually emitted by the ruminant animal, MeC is the mean methane concentration for each measurement, and CO2C is the mean carbon dioxide concentration for each measurement.

7. The ruminant methane emission measurement system of claim 6, wherein, The formula for calculating daily methane emission is: M CH4 =M CO2 ×((C CH4 × Mr CH4 ) / 22.4) : ((C CO2 × Mr CO2 ) / 22.4); wherein M CH4 is the daily methane emissions, M CO2 is the daily carbon dioxide emissions, C CH4 is the concentration of methane gas actually emitted by the ruminant animal, C CO2 is the concentration of carbon dioxide actually emitted by the ruminant animal, Mr CH4 is the molecular weight of methane, Mr CO2 is the molecular weight of carbon dioxide.

8. A method of measuring methane emission from a ruminant animal based on the ruminant animal methane emission measuring system according to any one of claims 1 to 7, characterized by, The application further relates to a method for real-time monitoring of methane emission of ruminants, comprising the following steps: automatically starting the gas collection and analysis process when the ruminant is milked and fed in the milking robot; synchronously measuring methane concentration and carbon dioxide concentration of the collected sample gas; identifying and screening effective concentration measurement records; calculating individual daily methane emission based on the screened effective concentration data and physiological parameters of the animal.

9. The ruminant methane emission measurement method according to claim 8, characterized by, The step of identifying and screening effective concentration measurement records comprises: (1) data preprocessing: obtaining all concentration original data in the milking period; (2) burping event identification: calculating the background value of environmental methane concentration during measurement; setting a burping peak detection threshold; scanning the methane concentration sequence to find significant peak values exceeding the threshold; (3) breathing effective period identification: calculating the 25% quantile of all carbon dioxide concentration data during measurement; removing the interval in which the carbon dioxide concentration is continuously lower than the 25% quantile in the carbon dioxide concentration sequence as the breathing effective period. (4) Effectiveness determination: In the same measurement period, at least one valid belching peak is identified, and at least one required carbon dioxide effective period exists, then all or part of the concentration data recorded in the milking process is marked as "valid record", and the average concentration of methane and carbon dioxide is calculated for subsequent calculation.

10. The ruminant methane emission measurement method according to claim 8, characterized by, The method further comprises the steps of: The calculated individual methane emission data is bound with individual identity information and transmitted to the pasture management system for group emission level analysis, extremely low or extremely high emission individual screening, methane emission trait selection or feeding management strategy optimization.

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