Method for rapidly screening and propagating improved variety genes of dairy cows

Abstract

The invention discloses a cow improved variety gene rapid screening and propagation method, and relates to the technical field of cow improved variety rapid propagation, the cow improved variety gene rapid screening and propagation method comprises the following operation steps: S1, sample collection; s2, screening improved variety genes; s3, carrying out primary propagation; s4, index determination; s5, evaluating genetic quality; and S6, result evaluation and propagation application. According to the rapid screening and propagation method for the improved variety genes of the dairy cows, after genetic quality evaluation, selection and propagation of the dairy cows of the next generation can be conveniently carried out according to the genetic quality evaluation result, the genetic quality of the dairy cows is comprehensively and accurately evaluated, the breeding process is more scientific and efficient, excellent breeding bulls and breeding cows can be found in time, and the breeding efficiency of the dairy cows is improved. Powerful decision support is provided for rapid propagation of improved variety genes, so that individuals with excellent gene combinations can be accurately screened out, the breeding period is greatly shortened, the selection accuracy is improved, and the production benefit and the economic benefit of cow breeding are further improved.

Description

Technical Field

[0001] The present invention relates to the technical field of rapid propagation of improved dairy cow breeds, in particular to a method for rapid screening and propagation of improved dairy cow breed genes. Background Art

[0002] Improved dairy cattle breeds are the foundation of dairy production. In modern dairy industry development strategies, genetic improvement of dairy cattle breeds and innovative utilization of germplasm resources are top priorities. The core of rapid breeding is in vitro fertilization, which involves fertilizing and transplanting activated sperm into oocytes in vitro to produce offspring, ultimately expanding breeding scale.

[0003] Currently, artificial insemination is usually required in the process of breeding high-quality cows, which mainly relies on the semen of excellent bulls for breeding, and requires more frequent genetic testing and analysis, which is not convenient for the rapid selection of high-quality genetic traits of high-quality dairy cows.

[0004] Therefore, in view of this, the existing structure and defects were studied and improved, and a method for rapid screening and propagation of improved dairy cow genes was proposed. Summary of the Invention

[0005] In view of the shortcomings of the existing technology, the present invention provides a method for rapid screening and propagation of improved dairy cow genes, which solves the problems raised in the above background technology.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solutions: a method for rapid screening and propagation of improved dairy cow genes, the method comprising the following steps:

[0007] S1. Sample Collection

[0008] Select healthy, well-developed dairy cows from different families with normal estrus cycles as samples, and collect a large number of tissue samples or blood samples from the cows to subsequently obtain genetic information of the cows in the samples;

[0009] S2. Screening of improved gene

[0010] Whole genome sequencing technology is used to perform genetic testing on collected samples, analyze the genetic composition of individual dairy cows, and accurately test a large number of gene loci to screen out individuals with genes related to excellent traits. The genetic information obtained from the testing is then organized and stored to establish a dairy cow genetic database.

[0011] S3, first generation expansion

[0012] Ovulation induction and human induction:

[0013] Healthy, reproductively sound cows are selected and superovulated. During a specific phase of their estrus cycle, gonadotropins are injected intramuscularly or subcutaneously to promote the simultaneous development of multiple follicles, allowing the cows to release multiple mature eggs within one estrus cycle.

[0014] Select high-quality bulls that have undergone genetic testing and production performance testing, collect semen from these high-quality bulls, conduct quality inspections on the semen immediately after collection to ensure the quality and vitality of the sperm, and perform artificial insemination on qualified semen;

[0015] Embryo transfer:

[0016] The process involves collecting early embryos from cows that have undergone superovulation and artificial insemination. Surgery is performed on the cows to remove the embryos from their uteri and place them in an embryo collector. The collected embryos are then assessed and screened for quality, with those that are well-developed and high-quality being selected for transplantation. These screened embryos are then transplanted into the uterus of recipient cows.

[0017] Then, healthy, moderately sized recipient cows with good reproductive performance are selected. The recipient cows need to undergo estrus synchronization treatment and inject hormones such as progesterone and prostaglandin to synchronize the reproductive physiological state of the recipient cows with that of the donor cows, so as to improve the success rate of embryo implantation and create a suitable uterine environment for embryo transplantation. In addition, high-quality feed is provided for pregnant cows to ensure balanced nutrition, meet the growth and development needs of the cows and fetuses, and ensure smooth pregnancy and calving of the cows.

[0018] Furthermore, the method for rapid screening and propagation of improved dairy cow genes also includes the following steps:

[0019] S4. Index determination

[0020] The production performance of the expanded dairy cow herd is measured, including milk production, milk components (such as milk protein rate, milk fat rate, etc.), reproductive performance (such as estrus cycle, conception rate, etc.), growth and development indicators (such as weight, body size, etc.) and disease resistance.

[0021] Furthermore, the method for rapid screening and propagation of improved dairy cow genes also includes the following steps:

[0022] S5. Genetic quality assessment

[0023] Data collection: Real-time collection and analysis of reproductive information such as estrus monitoring, breeding records, and pregnancy diagnosis after multiplication, as well as clarifying the relationship between the cow's parents, grandparents, and other relatives to build a complete pedigree chart;

[0024] Genotyping: The first generation of dairy cows is expanded and multiplied, and high-throughput whole-genome sequencing is performed on each cow in the first generation population to obtain the full gene sequence of the first generation population. The cows are then genotyped to detect their allele types at specific gene loci, and molecular markers that are closely linked to the target traits are screened.

[0025] Genetic parameter estimation: Use statistical methods to estimate the heritability of each trait, that is, the proportion of the trait's genetic variance in the total variance, and conduct genetic correlation analysis, that is, analyze the genetic correlation between different traits to understand their genetic relationships;

[0026] Individual index calculation: Based on the economic importance, heritability and genetic correlation of each trait, a selection index is constructed. The collected individual data are substituted into the selection index formula to calculate the selection index value for each cow.

[0027] Furthermore, the method for rapid screening and propagation of improved dairy cow genes also includes the following steps:

[0028] S6. Evaluation results and multiplication applications

[0029] Based on the results of genetic quality assessment, the next generation of dairy cows will be selected and propagated. That is, dairy cows with high selection indexes will be selected as breeding cows, and their offspring will be bred with good genes. Genetic testing technology will be used to conduct regular genetic monitoring of the propagation group to track the transmission and distribution of good genes in the group.

[0030] Furthermore, in the improved gene screening of step S2, the genetic composition of individual dairy cows is analyzed to determine genes related to traits such as milk production, milk quality, reproductive performance, and disease resistance.

[0031] Furthermore, in the primary generation propagation of step S3, ovulation induction and artificial timing are performed, and the specific stage of the estrus cycle of the fine-breed cow is usually the 9th to 12th day of the estrus cycle.

[0032] Furthermore, during the primary generation expansion in step S3, during ovulation induction and artificial insemination, the quality inspection of semen includes the detection of indicators such as sperm motility, density, and deformity rate.

[0033] Furthermore, in the primary generation expansion of step S3, embryo transplantation is usually performed on the 7th to 8th day after artificial insemination.

[0034] Furthermore, the method for rapid screening and propagation of improved dairy cow genes is applied to the technical field of dairy cow breeding.

[0035] The present invention provides a method for rapid screening and propagation of improved dairy cow genes, which has the following beneficial effects:

[0036] This method for rapid screening and propagation of superior genes in dairy cows can efficiently manage and analyze the genetic data of dairy cows through the dairy cow gene database, providing a basis for subsequent screening and propagation work; it uses advanced whole genome sequencing technology to accurately identify gene variations related to important economic traits of dairy cows, and compared with traditional detection methods, the detection throughput and accuracy are greatly improved; artificial insemination can accurately control the breeding time and semen quality, improve the conception rate and the transmission efficiency of superior genes; it enables superior cows to produce more high-quality eggs, thereby improving the transmission efficiency of superior genes; by regularly measuring the production performance of the dairy cow group after propagation, it is convenient to timely understand the production performance of the propagation group, providing data support for subsequent breeding and management; when collecting data during the genetic quality evaluation process, pedigree information helps to trace the cows Genetic origin, understanding the genetic background of its family and the transmission of excellent traits. After genetic quality evaluation, it is convenient to select and expand the next generation of dairy cows based on the results of genetic quality evaluation, and conduct a comprehensive and accurate evaluation of the genetic quality of dairy cows, making the breeding process more scientific and efficient, and being able to timely discover excellent breeding bulls and breeding cows, providing strong decision-making support for the rapid expansion of good genes, so that individuals with excellent gene combinations can be accurately screened, greatly shortening the breeding cycle, improving the accuracy of selection, and thus improving the production efficiency and economic benefits of dairy cattle farming. In addition, monitoring the changes in gene frequency can ensure that excellent genes are effectively maintained and improved in the group. According to the results of genetic monitoring, the feeding management plan can be adjusted and optimized in time to meet the different needs of the dairy cow group. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 The present invention is a schematic flow chart of the operating steps of a method for rapid screening and propagation of improved dairy cow genes. DETAILED DESCRIPTION

[0038] The following embodiments of the present invention are described in further detail with reference to the accompanying drawings and examples. The following examples are used to illustrate the present invention but are not intended to limit the scope of the present invention.

[0039] like Figure 1 As shown, the present invention provides a technical solution: a method for rapid screening and propagation of improved dairy cow genes, which includes the following steps:

[0040] S1. Sample Collection

[0041] Select healthy, well-developed dairy cows from different families with normal estrus cycles as samples, and collect a large number of tissue samples or blood samples from the cows to subsequently obtain genetic information of the cows in the samples;

[0042] S2. Screening of improved gene

[0043] Whole genome sequencing technology is used to perform genetic testing on collected samples to analyze the genetic composition of individual dairy cows, including genes related to traits such as milk production, milk quality, reproductive performance, and disease resistance. Simultaneously, a large number of gene loci are accurately tested to screen individuals with genes related to excellent traits. The genetic information obtained from the tests is then organized and stored to establish a dairy cow genetic database.

[0044] S3, first generation expansion

[0045] Ovulation induction and human induction:

[0046] Healthy, reproductively sound cows are selected and superovulated. Gonadotropins are injected intramuscularly or subcutaneously at a specific stage of their estrus cycle, usually on days 9-12, to promote the simultaneous development of multiple follicles, allowing the cow to release multiple mature eggs within one estrus cycle.

[0047] Select high-quality bulls that have undergone genetic testing and production performance testing, collect semen from these bulls, and immediately conduct a quality inspection of the semen after collection, including testing of indicators such as sperm motility, density, and deformity rate to ensure sperm quality and motility. Only qualified semen will be used for artificial insemination.

[0048] Embryo transfer:

[0049] Early embryos are collected from cows after superovulation and artificial insemination. Surgery is performed on the cows. Usually on the 7th to 8th day after artificial insemination, the embryos are removed from the cow's uterus and collected into an embryo collector. The collected embryos are then evaluated and screened for quality. Well-developed and high-quality embryos are selected for transplantation. The screened embryos are then transplanted into the uterus of the recipient cow.

[0050] Then, healthy, moderately sized recipient cows with good reproductive performance are selected. The recipient cows need to undergo estrus synchronization treatment. By injecting hormones such as progesterone and prostaglandin, the recipient cow's reproductive physiological state is synchronized with that of the donor cow to improve the success rate of embryo implantation and create a suitable uterine environment for embryo transplantation. Pregnant cows are also provided with high-quality feed to ensure balanced nutrition, meet the growth and development needs of the cow and fetus, and ensure smooth pregnancy and calving.

[0051] S4. Index determination

[0052] The production performance of the expanded dairy cow herd is measured, including milk production, milk composition (such as milk protein rate, milk fat rate, etc.), reproductive performance (such as estrus cycle, conception rate, etc.), growth and development indicators (such as weight, body size, etc.), and disease resistance.

[0053] S5. Genetic quality assessment

[0054] Data collection: Real-time collection and analysis of reproductive information such as estrus monitoring, breeding records, and pregnancy diagnosis after multiplication, as well as clarifying the relationship between the cow's parents, grandparents, and other relatives to build a complete pedigree chart;

[0055] Genotyping: The first generation of dairy cows is expanded and multiplied, and high-throughput whole-genome sequencing is performed on each cow in the first generation population to obtain the full gene sequence of the first generation population. The cows are then genotyped to detect their allele types at specific gene loci, and molecular markers that are closely linked to the target traits are screened.

[0056] Genetic parameter estimation: Use statistical methods to estimate the heritability of each trait, that is, the proportion of the trait's genetic variance in the total variance, and conduct genetic correlation analysis, that is, analyze the genetic correlation between different traits to understand their genetic relationships;

[0057] Individual index calculation: Based on the economic importance, heritability and genetic correlation of each trait, a selection index is constructed. The collected individual data are substituted into the selection index formula to calculate the selection index value for each cow;

[0058] S6. Evaluation results and multiplication applications

[0059] Based on the results of genetic quality assessment, the next generation of dairy cows will be selected and propagated. That is, dairy cows with high selection indexes will be selected as breeding cows, and their offspring will be bred with good genes. Genetic testing technology will be used to conduct regular genetic monitoring of the propagation group to track the transmission and distribution of good genes in the group.

[0060] The method for rapid screening and propagation of improved dairy cattle genes is applied in the technical field of dairy cattle breeding.

[0061] The dairy cow gene database can be used to efficiently manage and analyze the genetic data of dairy cows, providing a basis for subsequent screening and breeding work; the use of advanced whole genome sequencing technology can accurately identify genetic variations related to important economic traits of dairy cows, and compared with traditional detection methods, the detection throughput and accuracy are greatly improved; artificial insemination can accurately control the breeding time and semen quality, improve the conception rate and the transmission efficiency of excellent genes; enable good-quality cows to produce more high-quality eggs, and improve the transmission efficiency of excellent genes; by regularly measuring the production performance of the dairy cow group after breeding, it is convenient to timely understand the production performance of the breeding group, and provide data support for subsequent selection and management; when collecting data during the genetic quality evaluation process, pedigree information helps to trace the genetic origin of dairy cows and understand their The genetic background of the family and the transmission of excellent traits. After the genetic quality assessment, it is convenient to select and expand the next generation of dairy cows according to the results of the genetic quality assessment, and conduct a comprehensive and accurate assessment of the genetic quality of dairy cows, making the breeding process more scientific and efficient, and being able to timely discover excellent breeding bulls and breeding cows, providing strong decision-making support for the rapid expansion of good genes, so that individuals with excellent gene combinations can be accurately screened, greatly shortening the breeding cycle, improving the accuracy of selection, and thus improving the production efficiency and economic benefits of dairy cattle farming. In addition, the changes in gene frequency can be monitored later to ensure that excellent genes are effectively maintained and improved in the group. According to the results of genetic monitoring, the feeding management plan can be adjusted and optimized in time to meet the different needs of the dairy cow group.

[0062] In summary, if Figure 1 As shown, the method for rapid screening and propagation of improved dairy cow genes comprises the following steps when used:

[0063] S1. Sample collection: Select healthy, well-developed dairy cows from different families with normal estrus cycles as samples, and collect a large number of tissue samples or blood samples from the cows to subsequently obtain genetic information of the cows in the samples;

[0064] S2. Screening for superior genetics: Whole-genome sequencing technology is used to perform genetic testing on collected samples, analyzing the genetic makeup of individual dairy cows, including genes related to traits such as milk production, milk quality, reproductive performance, and disease resistance. Simultaneously, a large number of gene loci are precisely tested to identify individuals with genes associated with superior traits. The genetic information obtained is then organized and stored to establish a dairy cow genetic database.

[0065] S3. Primary generation expansion: Select healthy and good-breeding cows, and perform superovulation on the selected cows. At a specific stage of their estrus cycle, usually on the 9th to 12th day of the estrus cycle, inject gonadotropins intramuscularly or subcutaneously to promote the simultaneous development of multiple follicles, so that the cows can release multiple mature eggs in one estrus cycle. Select excellent bulls that have undergone genetic testing and production performance testing, collect semen from excellent bulls, and immediately conduct quality inspections on the semen after collection, including testing of indicators such as sperm motility, density, and deformity rate to ensure the quality and motility of the sperm. Perform artificial insemination on qualified semen. Collect early embryos from cows that have undergone superovulation and artificial insemination, and perform surgery on the cows. Usually on the 7th to 8th day after artificial insemination, embryos are removed from the cow's uterus and collected into an embryo collector. The collected embryos are then evaluated and screened for quality. Well-developed and high-quality embryos are selected for transplantation. The screened embryos are then transplanted into the uterus of the recipient cow. Healthy recipient cows of moderate size and good reproductive performance are then selected. The recipient cows undergo estrus synchronization treatment and are injected with hormones such as progesterone and prostaglandin to synchronize their reproductive physiological state with that of the donor cow, thereby increasing the success rate of embryo implantation and creating a suitable uterine environment for embryo transplantation. High-quality feed is also provided to the pregnant cows to ensure balanced nutrition, meet the growth and development needs of the cow and fetus, and ensure smooth pregnancy and calving.

[0066] S4. Index measurement: The production performance of the expanded dairy cow herd is measured, including milk production, milk composition (such as milk protein rate, milk fat rate, etc.), reproductive performance (such as estrus cycle, conception rate, etc.), growth and development indicators (such as weight, body size, etc.), and disease resistance.

[0067] S5. Genetic quality assessment: Real-time collection and analysis of reproductive information such as estrus monitoring, breeding records, and pregnancy diagnosis after breeding, and clarifying the relationship between the parents, grandparents, and other relatives of the dairy cows to build a complete pedigree chart; breeding the first-generation dairy cow population, and high-throughput whole-genome sequencing of each dairy cow in the first-generation population to obtain the full gene sequence of the first-generation population, and genotyping of individual dairy cows to detect their allele types at specific gene loci, and then screening out molecular markers that are closely linked to the target traits; using statistical methods to estimate the heritability of each trait, that is, the proportion of the genetic variance of the trait in the total variance, and conduct genetic correlation analysis, that is, analyze the genetic correlation between different traits to understand their genetic relationship; construct a selection index based on the economic importance, heritability and genetic correlation of each trait, substitute the collected individual data into the selection index formula, and calculate the selection index value for each dairy cow;

[0068] S6. Evaluation results and propagation application: Based on the results of genetic quality evaluation, the next generation of dairy cows will be selected and propagated. That is, dairy cows with high selection indexes will be selected as breeding cows, and their good genetic offspring will be bred with them. Genetic testing technology will be used to conduct regular genetic monitoring of the propagation group to track the transmission and distribution of good genes in the group.

[0069] The embodiments of the present invention are presented for purposes of illustration and description and are not intended to be exhaustive or to limit the invention to the disclosed forms. Many modifications and variations will be apparent to those skilled in the art. The embodiments are chosen and described in order to better illustrate the principles of the invention and its practical application and to enable those skilled in the art to understand the invention and design various embodiments with various modifications as suited for specific applications.

Claims

1. A method for rapid screening and propagation of improved dairy cattle genes, characterized by: The method for rapid screening and propagation of improved dairy cow genes comprises the following steps: S1. Sample Collection Select healthy, well-developed dairy cows from different families with normal estrus cycles as samples, and collect a large number of tissue samples or blood samples from the cows to subsequently obtain genetic information of the cows in the samples; S2. Screening of improved gene Whole genome sequencing technology is used to perform genetic testing on collected samples, analyze the genetic composition of individual dairy cows, and accurately test a large number of gene loci to screen out individuals with genes related to excellent traits. The genetic information obtained from the testing is then organized and stored to establish a dairy cow genetic database. S3, first generation expansion Ovulation induction and human induction: Healthy, reproductively sound cows are selected and superovulated. During a specific phase of their estrus cycle, gonadotropins are injected intramuscularly or subcutaneously to promote the simultaneous development of multiple follicles, allowing the cows to release multiple mature eggs within one estrus cycle. Select high-quality bulls that have undergone genetic testing and production performance testing, collect semen from these high-quality bulls, conduct quality inspections on the semen immediately after collection to ensure the quality and vitality of the sperm, and perform artificial insemination on qualified semen; Embryo transfer: The process involves collecting early embryos from cows that have undergone superovulation and artificial insemination. Surgery is performed on the cows to remove the embryos from their uteri and place them in an embryo collector. The collected embryos are then assessed and screened for quality, with those that are well-developed and high-quality being selected for transplantation. These screened embryos are then transplanted into the uterus of recipient cows. Then, healthy, moderately sized recipient cows with good reproductive performance are selected. The recipient cows need to undergo estrus synchronization treatment and inject hormones such as progesterone and prostaglandin to synchronize the reproductive physiological state of the recipient cows with that of the donor cows, so as to improve the success rate of embryo implantation and create a suitable uterine environment for embryo transplantation. In addition, high-quality feed is provided for pregnant cows to ensure balanced nutrition, meet the growth and development needs of the cows and fetuses, and ensure smooth pregnancy and calving of the cows.

2. The method for rapid screening and propagation of improved dairy cattle genes according to claim 1, characterized in that: The method for rapid screening and propagation of improved dairy cow genes also includes the following steps: S4. Index determination The production performance of the expanded dairy cow herd is tested, including milk production, milk composition, reproductive performance, growth and development indicators, and disease resistance.

3. The method for rapid screening and propagation of improved dairy cow genes according to claim 1, characterized in that: The method for rapid screening and propagation of improved dairy cow genes also includes the following steps: S5. Genetic quality assessment Data collection: Real-time collection and analysis of reproductive information such as estrus monitoring, breeding records, and pregnancy diagnosis after multiplication, as well as clarifying the relationship between the cow's parents, grandparents, and other relatives to build a complete pedigree chart; Genotyping: The first generation of dairy cows is expanded and multiplied, and high-throughput whole-genome sequencing is performed on each cow in the first generation population to obtain the full gene sequence of the first generation population. The cows are then genotyped to detect their allele types at specific gene loci, and molecular markers that are closely linked to the target traits are screened. Genetic parameter estimation: Use statistical methods to estimate the heritability of each trait, that is, the proportion of the trait's genetic variance in the total variance, and conduct genetic correlation analysis, that is, analyze the genetic correlation between different traits to understand their genetic relationships; Individual index calculation: Based on the economic importance, heritability and genetic correlation of each trait, a selection index is constructed. The collected individual data are substituted into the selection index formula to calculate the selection index value for each cow.

4. The method for rapid screening and propagation of improved dairy cattle genes according to claim 1, characterized in that: The method for rapid screening and propagation of improved dairy cow genes also includes the following steps: S6. Evaluation results and multiplication applications Based on the results of genetic quality assessment, the next generation of dairy cows will be selected and propagated. That is, dairy cows with high selection indexes will be selected as breeding cows, and their offspring will be bred with good genes. Genetic testing technology will be used to conduct regular genetic monitoring of the propagation group to track the transmission and distribution of good genes in the group.

5. The method for rapid screening and propagation of improved dairy cow genes according to claim 1, characterized in that: In the improved gene screening of step S2, the genetic composition of individual dairy cows is analyzed, including genes related to traits such as milk production, milk quality, reproductive performance, and disease resistance.

6. The method for rapid screening and propagation of improved dairy cattle genes according to claim 1, characterized in that: In the primary generation propagation of step S3, ovulation induction and artificial timing are performed, and the specific stage of the estrus cycle of the fine-breed cow is usually the 9th to 12th day of the estrus cycle.

7. The method for rapid screening and propagation of improved dairy cattle genes according to claim 1, characterized in that: During the primary generation expansion in step S3, during ovulation induction and artificial insemination, the quality inspection of semen includes the detection of indicators such as sperm motility, density, and deformity rate.

8. The method for rapid screening and propagation of improved dairy cow genes according to claim 1, characterized in that: In the primary generation expansion of step S3, embryo transfer is usually performed on the 7th to 8th day after artificial insemination.

9. A method for rapid screening and propagation of improved dairy cattle genes according to any one of claims 1 to 8, characterized in that: The method for rapid screening and propagation of improved dairy cow genes is applied to the technical field of dairy cow breeding.

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