Method for rapidly, effectively and quantitatively evaluating carbon emission of genetic engineering pigs

Abstract

The invention provides a method for rapidly, effectively and quantitatively evaluating carbon emission of genetic engineering pigs, and belongs to the technical field of genetic engineering animals. Genetically engineered pigs are divided into different groups of breeding boars, non-pregnant sows, pregnant sows, lactating sows, lactating piglets, nursing piglets, growing pigs, growing pigs and fattening pigs, and intestinal methane emission factors and excrement methane emission flux of the pigs in different growth periods are respectively measured according to the characteristics of the pigs in different growth periods. And calculating the total emission amount of the intestinal methane and the total emission amount of the excrement methane by using the intestinal methane emission factor and the excrement methane emission flux.

Description

Technical Field

[0001] The invention relates to the technical field of genetically engineered animals, and in particular to a method for rapidly and effectively quantitatively evaluating carbon emissions of genetically engineered pigs. Background Art

[0002] Genetically engineered animals are animals that humans manipulate or modify specific regions of their genomes based on their subjective will and needs using modern genetics and molecular and cellular bioengineering techniques, thereby completely changing the biological heredity at the genomic level and obtaining animal individuals that can be continuously and stably inherited to offspring.

[0003] Pigs are one of the important livestock animals and an important source of meat in my country. They are closely related to people's daily lives. With the rapid development of transgenic technology, pigs have been pushed onto the stage of breeding improvement, medical application, and commercial operation, and are facing unprecedented opportunities. my country is the country with the richest pig breed resources in the world. Local pig breeds are not only diverse, but also have different germplasm characteristics. After long-term domestication and breeding, most local pig breeds have the characteristics of excellent meat quality, high fertility, strong stress resistance, and tolerance to roughage. However, the disadvantages of low lean meat rate, slow growth rate, and low feed conversion rate of local breeds limit their large-scale breeding. The application of transgenic technology provides a new way to better utilize the excellent genetic resources of local pig breeds in my country.

[0004] Genetically engineered pigs have a good development prospect, which can improve the production performance of pigs, increase the lean meat rate and improve the muscle quality. However, the use of genetic engineering will inevitably change the body functions of pigs during growth, among which carbon emissions from the pig's respiratory tract and intestines are a major problem.

[0005] Carbon emissions from the livestock and poultry farming industry are widely present in the entire process of pre-production, production and post-production. From the perspective of the life cycle, the carbon emissions of the entire livestock and poultry farming industry can be subdivided into six system boundaries: intestinal fermentation, manure management system, feed grain planting, feed transportation and processing, energy consumption in the breeding link, and livestock and poultry slaughtering and processing. Among them, livestock and poultry intestinal fermentation and manure management system are the main sources of carbon emissions from the livestock and poultry farming industry.

[0006] At present, the main carbon emission accounting methods for the livestock industry include the OECD method, the IPCC coefficient method (emission factor method) and the mass balance method. The OECD method estimates the methane production of ruminants based on the digestibility of feed ingested by ruminants and the nutritional level of feed based on the energy required to maintain the body. This method requires detailed basic data and the evaluation process is relatively complicated. The mass balance method measures the gas flow rate in the space where the animals are located and the change in methane concentration in the airflow, and substitutes these parameters into the formula to calculate the methane emissions. This method can only measure carbon emissions in a small range. However, the existing accounting methods do not take into account the differences in carbon emissions between young and adult livestock and poultry, so it is impossible to accurately calculate the carbon emissions of livestock and poultry at different growth stages from entry to exit.

[0007] For example, the existing technology based on LCA calculates the carbon emissions of typical pig supply chains in Jiangxi Province. Taking the carbon emissions of typical pigs in Jiangxi as the research object, the full life cycle assessment (LCA) method is used to construct a carbon emission calculation framework including feed, pig breeding, pig raising, slaughtering and processing, packaging and cutting, transportation and storage, etc. The actual technical data of the pig industry in Poyang Lake, Jiangxi Province is used to specifically calculate the carbon emissions of Jiangxi pork. The emission factors used are derived from the "IPCC 2006 National Greenhouse Gas Inventory Guidelines (2019 Revised Edition)", but the above emission factors are all average emission factors stipulated by local regulations.

[0008] And because genetic engineering changes the growth characteristics of pigs, which results in different energy consumption from ordinary pigs, the carbon emission ratio of pigs will inevitably change. Conventional carbon emission testing methods and the emission factors used are not suitable for genetically engineered pigs. Therefore, it is urgent to propose a method that can quickly and effectively quantitatively evaluate the carbon emissions of genetically engineered pigs. Summary of the invention

[0009] In view of this, the present invention provides a method for quickly and effectively quantitatively evaluating the carbon emissions of genetically engineered pigs. The genetically engineered pigs are divided into different groups according to their growth cycles, and then the intestinal methane emission factors and fecal methane emission fluxes are respectively measured, and the above-mentioned intestinal methane emission factors and fecal methane emission fluxes are used to calculate carbon emissions. The carbon emissions of genetically engineered pigs in different growth periods can be measured, and the carbon emissions of genetically engineered pigs can be quickly and effectively quantitatively evaluated.

[0010] The method for rapidly and effectively quantitatively evaluating carbon emissions of genetically engineered pigs in the present invention comprises the following steps:

[0011] (1) The genetically engineered pigs were divided into boars, empty sows, pregnant sows, lactating sows, lactating piglets, nursery piglets, growing pigs, finishing pigs and fattening pigs, and the genetically engineered pigs in different groups were tested separately;

[0012] (2) Use an open breathing chamber to measure the change in methane concentration over a certain period of time, which is recorded as the intestinal methane emission factor E1 i ;

[0013] (3) Collect feces and use the static chamber method to measure the feces methane emission flux E2 over a certain period of time j ;

[0014] (4) Apply the methane emission factor E1 in step (2) i The intestinal fermentation methane emissions of different groups of genetically engineered pigs were calculated and added together to obtain the total intestinal methane emissions;

[0015] (5) Apply the fecal methane emission flux E2 in step (3) j The fecal methane emissions of different groups of genetically engineered pigs were calculated and added together to obtain the total fecal methane emissions;

[0016] (6) The total intestinal methane emissions and fecal methane emissions of different groups of genetically engineered pigs were added together to obtain the carbon emissions of genetically engineered pigs.

[0017] Preferably, the test method for the intestinal methane emission factor in step (2) is:

[0018] Different groups of genetically engineered pigs were placed in open breathing boxes. The pigs were free to eat and drink water during the experiment and adapted for 24 hours. Then the methane emission of each pig was measured for 24 hours. The average value of each group was recorded as the intestinal methane emission factor E1. i .

[0019] Preferably, the methane emission flux E2 in step (3) is j The calculation method is as follows: collect 1 kg of feces from different groups of genetically engineered pigs, place the static collection box in a ventilated outdoor place, measure the methane emission for 24 hours, measure continuously for one week, and take the average value to obtain the methane emission flux E2 j .

[0020] Preferably, the calculation method of the total amount of intestinal methane emissions in step (4) is:

[0021] CH4 肠道 =∑(N i ·E1 i )·D (1)

[0022] In formula (1), CH4 肠道 is the total enteric methane emission, N i is the number of genetically engineered pigs in each group, and D is the number of calculation days.

[0023] Preferably, the total amount of feces methane emissions in step (5) is calculated as follows:

[0024] CH4粪便 =∑(N i ·m i ·E1 j )·D (2)

[0025] In formula (2), CH4 粪便 is the total amount of methane emitted from manure; m i is the daily feces volume of each pig (kg); preferably, the carbon emission calculation method of the genetically engineered pigs in step (6) is as follows:

[0026] CH4 总 =CH4 肠道 +CH4 粪便 (3)

[0027] In formula (3), CH4 总 Carbon emissions for genetically engineered pigs.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] The present invention provides a method for rapid and effective quantitative evaluation of carbon emissions of genetically engineered pigs, wherein the genetically engineered pigs are divided into different groups, namely, boars, empty sows, pregnant sows, lactating sows, lactating piglets, nursery piglets, growing pigs, finishing pigs and fattening pigs, and the intestinal methane emission factors and fecal methane emission fluxes of the pigs at different growth stages are respectively measured. The intestinal methane emission factors and fecal methane emission fluxes are then used to calculate the total intestinal methane emissions and the total fecal methane emissions. DETAILED DESCRIPTION

[0030] The present invention will be further described below in conjunction with the embodiments.

[0031] Example 1

[0032] A method for rapid and effective quantitative evaluation of carbon emissions from genetically engineered pigs, the steps are as follows:

[0033] (1) 45 wild-type Meishan pigs of the same breed as MSTN gene-edited pigs (MSTN - / - ), as experimental subjects, including boars (A), empty sows (B), pregnant sows (C), lactating sows (D), lactating piglets (E), nursery piglets (F), growing pigs (G), finishing pigs (H) and fattening pigs (I), 5 heads each, and different groups of genetically engineered pigs were tested separately;

[0034] (2) The genetically engineered pigs in different groups were placed in an open-circuit gas metabolism system (Sable Systems International, Las Vegas, NV, USA) for measurement. The pigs were allowed to eat and drink freely during the experiment and adapted for 24 hours. The methane emissions of each pig were then measured for 24 hours, and the average value was recorded as the intestinal methane emission factor E1. i ;

[0035] Specifically, the boar group is E1 A , empty sow group is E1 B , pregnant sow group is E1 C , lactating sow group was E1 D , suckling pig group was E1 E , the nursery piglet group is E1 F , growing pig group is E1 G , growing pig group is E1 H and fattening pigs group E1 I .

[0036] (3) Collect 1 kg of feces from each group of genetically engineered pigs, place the static collection box in a ventilated outdoor place, measure the methane emission for 24 hours, and measure it continuously for one week. Take the average value to obtain the methane emission flux E2 j ;

[0037] Specifically, the boar group is E2 A , empty sow group is E2 B , pregnant sow group was E2 C , lactating sow group: E2 D , suckling pig group was E2 E , the nursery piglet group is E2 F , growing pig group is E2 G , growing pig group is E2 H and E2 for fattening pigs I .

[0038] (4) Apply the methane emission factor E1 in step (2) i The intestinal fermentation methane emissions of different groups of genetically engineered pigs were calculated and added to obtain the total intestinal methane emissions. The calculation method is:

[0039] CH4 肠道 =∑(N i ·E1 i )·D (1)

[0040] In formula (1), CH4 肠道 is the total amount of enteric methane emissions; N i is the number of genetically engineered pigs in each group, which is 5 in this embodiment; and D is the number of calculation days.

[0041] (5) Apply the fecal methane emission flux E2 in step (3) j The fecal methane emissions of different groups of genetically engineered pigs were calculated and added together to obtain the total fecal methane emissions. The calculation method is:

[0042] CH4 粪便 =∑(N i ·m i E1 j )·D (2)

[0043] In formula (2), CH4 粪便 is the total amount of methane emitted from manure; m i is the daily feces volume of each pig (kg); N i is the number of genetically engineered pigs in each group, which is 5 in this embodiment; and D is the number of calculation days.

[0044] (6) The total methane emissions and fecal methane emissions of different groups of genetically engineered pigs were added together to obtain the carbon emissions of genetically engineered pigs. The calculation method is as follows:

[0045] CH4 总 =CH4 肠道 +CH4 粪便 (3)

[0046] In formula (3), CH4 总 Carbon emissions for genetically engineered pigs.

[0047] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for rapid and effective quantitative evaluation of carbon emissions from genetically engineered pigs, characterized in that: The following steps are involved: (1) The genetically engineered pigs were divided into boars, empty sows, pregnant sows, lactating sows, lactating piglets, nursery piglets, growing pigs, finishing pigs and fattening pigs, and the genetically engineered pigs in different groups were tested separately; (2) Use an open breathing chamber to measure the change in methane concentration over a certain period of time, which is recorded as the intestinal methane emission factor E1 i ; (3) Collect feces and use the static chamber method to measure the feces methane emission flux E2 over a certain period of time j ; (4) Apply the methane emission factor E1 in step (2) i The intestinal fermentation methane emissions of different groups of genetically engineered pigs were calculated and added together to obtain the total intestinal methane emissions; (5) Apply the fecal methane emission flux E2 in step (3) j The fecal methane emissions of different groups of genetically engineered pigs were calculated and added together to obtain the total fecal methane emissions; (6) The total intestinal methane emissions and fecal methane emissions of different groups of genetically engineered pigs were added together to obtain the carbon emissions of genetically engineered pigs.

2. The method for rapid and effective quantitative evaluation of carbon emissions of genetically engineered pigs according to claim 1, characterized in that: The test method for the intestinal methane emission factor in step (2) is: Different groups of genetically engineered pigs were placed in open breathing boxes. The pigs were free to eat and drink water during the experiment and adapted for 24 hours. Then the methane emission of each pig was measured for 24 hours. The average value of each group was recorded as the intestinal methane emission factor E1. i .

3. The method for rapid and effective quantitative evaluation of carbon emissions of genetically engineered pigs according to claim 1, characterized in that: Step (3) Methane emission flux E2 j The calculation method is as follows: collect 1 kg of feces from different groups of genetically engineered pigs, place the static collection box in a ventilated outdoor place, measure the methane emission for 24 hours, measure continuously for one week, and take the average value to obtain the methane emission flux E2 j .

4. The method for rapid and effective quantitative evaluation of carbon emissions of genetically engineered pigs according to claim 1, characterized in that: The calculation method of the total amount of intestinal methane emissions in step (4) is: CH4 肠道 =∑(N i ·E1 i )·D (1) In formula (1), CH4 肠道 is the total enteric methane emission, N i is the number of genetically engineered pigs in each group, and D is the number of calculation days.

5. The method for rapid and effective quantitative evaluation of carbon emissions of genetically engineered pigs according to claim 1, characterized in that: The calculation method of the total amount of fecal methane emissions in step (5) is: CH4 粪便 =∑(N i ·m i ·E1 j )·D (2) In formula (2), CH4 粪便 is the total amount of methane emitted from manure; m i The daily feces volume (kg) of each pig.

6. The method for rapid and effective quantitative evaluation of carbon emissions of genetically engineered pigs according to claim 1, characterized in that: The carbon emission calculation method of the genetically engineered pigs in step (6) is as follows: CH4 总 =CH4 肠道 +CH4 粪便 (3) In formula (3), CH4 总 Carbon emissions for genetically engineered pigs.