Breeding method for new high-reproduction strain of Dazu black goats
Through genome selection and atresia breeding technology, combined with genetic evaluation models, the problem of the decline in the reproduction rate of Dazu black goats was solved, which significantly improved the reproductive performance and genetic structure, improved the breeding efficiency, and promoted the development of animal husbandry.
Patent Information
- Application Number
- CN202411306625.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-19
- Publication Date
- 2024-12-20
AI Technical Summary
The breeding rate within the Dazu black goat breed has declined, and the average weight of the offspring of high-prosperity ewes is low, and it grows slowly, making it difficult to be selected and retained, resulting in an increase in the proportion of single-child births and a decrease in the proportion of lamb production.
Genome selection technology is used to select individuals with fast growth speed and high fertility to form breeding families, and accurately evaluate individual genetics through atresia breeding and genetic assessment models, establish a BLUP genetic assessment system, implement genome breeding value estimation, avoid all compatriots and half Mercy mating, random mating, selection and elimination of each generation, and the candidate genes are preferred for genetic improvement.
It significantly improved the low heritability pregnancy rate and somatic cell score of Dazu black goats, enriched the breeding structure, improved reproductive performance, improved the economic benefits of breeding, and promoted the high-quality development of animal husbandry.
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Figure CN119162331A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the field of animal breeding, and in particular to a method for breeding a new high-fertility strain of Dazu black goats. Background Art
[0002] Dazu Black Goat is a breed with high reproduction rate among meat goat breeds in my country, but there are still large differences in the reproduction rate of different individuals within the breed. Most farms pay more attention to the growth rate of goats, and usually use phenotypic data such as birth weight, weaning weight, first mating age weight, body shape and appearance to select reserve breeding goats; under such conventional breeding methods, the reproduction performance data is basically invalid, and the offspring of most high-breeding ewes generally have a lower average weight and slow growth due to high production, making it difficult to be selected. As a result, the proportion of single births within the breed has increased year by year, the proportion of producing multiple lambs has decreased, and the overall reproduction rate has shown a downward trend. Summary of the invention
[0003] In order to solve the above technical problems, the present invention provides a method for breeding a new high-fertility strain of Dazu black goats, which can fully tap the potential of Dazu black goat genetic resources, enrich the genetic structure of the breed, and further improve the overall breeding performance of Dazu black goats.
[0004] The technical solution adopted by the present invention to solve the technical problem is: a method for breeding a new high-fertilization strain of Dazu black goats, comprising the following steps:
[0005] S1, basic group formation, using genomic selection technology to select individuals with fast growth rate and high fertility to form the Dazu black goat breeding family, collecting blood samples for SNP detection, and establishing pedigree files;
[0006] S2, closed breeding, which starts with the selection of the basic group, then closes the herd, and conducts corresponding selection and matching in the closed small group based on production performance, body shape and appearance, and pedigree source;
[0007] S3, expansion and improvement, use genetic evaluation models to evaluate the genetic stability of goat high-yield traits and the molecular genetic stability of new breed groups, implement precise individual genetic evaluation of goats, and use cross-validation method to verify the accuracy of breeding values, and estimate the whole genome breeding values of the established breeding group.
[0008] Preferably, in step S1, individuals that meet the requirements of high reproduction and fast growth are selected as the breeding base group (more than 800 ewes and 30 rams);
[0009] The high reproduction rate is: the multiparous ewe gives birth to two consecutive litters, with an average number of live lambs per litter of ≥2.7; the ram's ejaculation volume is ≥0.70mL, the sperm motility is ≥90%, and the conception rate with the mating ewe is ≥270%;
[0010] The rapid growth: the weight of the ewe reaches more than 18.5kg at 6 months old, and the weight at one year old reaches more than 27kg; the weight of the ram reaches more than 21.5kg at 6 months old, and the weight at one year old reaches more than 31kg.
[0011] Preferably, in step S2, 600 ewes and 20 rams are selected for each generation, and a random mating system is implemented to avoid mating between full siblings and half siblings.
[0012] Preferably, in step S2, the basic group is subjected to closed breeding for 4 generations without introducing foreign blood, so that the average inbreeding coefficient of the group naturally increases to 10% to 15%.
[0013] Preferably, in step S2, the lambing number and weight data of the sheep are determined, and blood is collected from the jugular vein after marking, genomic DNA is extracted, SNP genotypes are performed using whole genome resequencing, and SNP effects are statistically calculated; at the same time, a BLUP genetic evaluation system and model are established.
[0014] Preferably, in step S2, genes PSTPIP2, C7orf57, CDKAL1, CCL19, FGF9, SGCG, SIPA1L1 and FIGN are used as candidate genes for regulating goat body shape traits;
[0015] Genes ATP1, LRRC4C, SPCS2, XRRA1, CELF4, NTM, TMEM45B, ATE, and FGFR2 were selected as candidate genes regulating breast traits;
[0016] Genes ENSCHIG00000017110, SLC9A8, GLRB, GRIA2, GASK1B and ENSCHIG0000002628 were selected as candidate genes regulating the trait of litter size.
[0017] Preferably, in step S3, the selected sheep flock is graded according to the evaluation results of production performance, body shape and appearance, and the principle of grade selection is that the grade of rams is higher than that of ewes.
[0018] Beneficial effects of the present invention:
[0019] The present invention can fully tap the potential of Dazu black goat genetic resources, significantly improve the pregnancy rate, estrus and somatic cell score of low heritability, enrich the genetic structure of the breed, and compared with traditional breeding methods, genomic selection has the advantages of improving selection accuracy and achieving early selection. It can further improve the overall reproductive performance of Dazu black goats, thereby improving the economic benefits of Dazu black goat breeding and promoting the high-quality development of my country's animal husbandry. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only one of the drawings of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0021] Figure 1 A schematic diagram of steps of an embodiment of the present invention; DETAILED DESCRIPTION
[0022] In order to deepen the understanding of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. The embodiments are only used to explain the present invention and do not limit the protection scope of the present invention.
[0023] Example
[0024] 1. Basic group establishment
[0025] A basic herd was established in Chongqing Tengda Animal Husbandry Co., Ltd. According to the standard physical appearance characteristics of "Dazu Black Goat" (DB50 / T38-2011), with reproduction and growth traits as the main economic indicators, the genomic selection (GS) technology was used to select individuals with fast growth rate and high fertility to form the Dazu Black Goat breeding family, and blood samples were collected for SNP detection to establish a pedigree file. No less than 5 rams with excellent Dazu Black Goats from different families were used as line ancestors, and 50 to 100 Dazu Black Goat ewes were mated with them to build no less than 5 families. Combining marker-assisted selection and multi-trait comprehensive selection index method, genetic evaluation and selection of excellent individuals are carried out, while taking into account the relative independence of the ram family, and individuals that meet the requirements of high reproduction (multiparous ewes give birth to two consecutive litters, with an average number of live lambs per litter ≥2.7; rams' ejaculation volume ≥0.70mL, sperm motility ≥90%, and conception rate with ewes ≥270%) and fast growth (ewes weighing more than 18.5kg at 6 months of age and more than 27kg at one year old; rams weighing more than 21.5kg at 6 months of age and more than 31kg at one year old) are selected as the breeding base group (more than 800 ewes and 30 rams).
[0026] 2. Closed breeding
[0027] Start with the selection of the basic flock (more than 800 ewes and 30 rams), then close the herd, and carry out corresponding selection and mating in the closed small flock according to production performance, body shape, appearance, pedigree, etc. Strict closed breeding and successive breeding are implemented, and each generation of breeding sheep must be selected from the offspring of the basic flock. 600 ewes and 20 rams are selected for each generation, and a random mating system is implemented to avoid mating with full siblings and half siblings to reduce the inbreeding coefficient and prevent gene drift. Combined with rapid breeding technologies such as synchronous estrus, timed insemination, and embryo transplantation, the breeding process is accelerated. The basic group is closed for 4 generations without introducing foreign blood in the middle, so that the average inbreeding coefficient of the group naturally rises to 10% to 15%, and the gene homozygosity of the main selected traits and the genetic similarity between individuals are improved. Taking high reproduction, fast growth and other excellent traits as indicators, the number of lambs, weight and other data of the sheep were measured, and 8mL of blood was collected from the jugular vein after marking, and genomic DNA was extracted. Whole genome resequencing was used for SNP genotype, and SNP effects were statistically calculated. At the same time, a BLUP genetic evaluation system and model were established, and molecular marker technology was used to carry out genetic improvement and germplasm innovation on the basic breeding population of Dazu Black Goats. Through the selection and directional breeding of this variety, a new group of Dazu Black Goats with fast growth rate and strong reproductive performance was formed. Further determination of production indicators such as reproductive performance, growth and development, and meat traits of the selected breeding population was carried out, and elimination and renewal were continuously implemented to fully tap the excellent germplasm resources and excellent characteristic traits of Dazu Black Goats, and build a core breeding population of more than 1,000.
[0028] Genes PSTPIP2, C7orf57, CDKAL1, CCL19, FGF9, SGCG, SIPA1L1, and FIGN were selected as candidate genes regulating body shape traits in goats;
[0029] Genes ATP1, LRRC4C, SPCS2, XRRA1, CELF4, NTM, TMEM45B, ATE, and FGFR2 were selected as candidate genes regulating breast traits;
[0030] Genes ENSCHIG00000017110, SLC9A8, GLRB, GRIA2, GASK1B and ENSCHIG0000002628 were selected as candidate genes regulating the trait of litter size.
[0031] 3. Expansion and improvement
[0032] The genetic evaluation model is used to evaluate the genetic stability of high-yield traits of goats (daily weight gain, lambing rate, feed conversion rate and meat quality, etc.) and the molecular genetic stability of new strains. The precise individual genetic evaluation of goats is implemented, and the accuracy of breeding values is verified by cross-validation method. The breeding values of the established breeding group are estimated by whole genome. Production group mutton sheep or larger breeding groups generally adopt grade selection. The selected sheep group is divided into four grades, namely special grade, first grade, second grade and third grade, according to the evaluation results of production performance and body shape and appearance, and the rams are determined and matched respectively. The rams must also be graded. The principle of grade selection is that the grade of rams must be higher than that of ewes. Combined with the results of individual genetic evaluation, the breeding performance is selected as the main selection trait, and the breeding performance of ewes and rams meets the special grade standard of "Dazu Black Goat" (DB50 / T 38-2011). The multiparous ewes give birth to 2 consecutive litters, with ≥3 live lambs per litter; the rams have an ejaculation volume of ≥0.75mL, a sperm motility of ≥95%, and a conception rate of ≥300% with ewes. The growth traits of ewes and rams meet the first-class sheep standards of "Dazu Black Goat" (DB50 / T 38-2011). Ewes weighing more than 18.5kg at 6 months of age and more than 27kg at one year old; rams weighing more than 21.5kg at 6 months of age and more than 31kg at one year old enter the core group. Rapid propagation technology is used to shorten the generation interval, and continuous selection and breeding of the core group is carried out for 3 to 5 generations. Molecular assisted marker technology (SNP) is used to evaluate the breeding value of the newly formed strain population and verify the accuracy of the breeding value. When the new strain is bred, the weight of the adult ram is above 45kg, the slaughter rate is above 50%, the weight of the ewe is above 35kg, the slaughter rate is above 45%, the lambing rate is above 250%, and the average level of the group is high. The average inbreeding coefficient of the group reaches 10% to 13%, and the average kinship coefficient is above 20%.
[0033] For the groups with relatively stable reproduction performance after 3-5 generations and basically reaching the breeding goal, some groups are selected to Chongqing Dazu District Ruifeng Modern Agriculture Development Co., Ltd., Chongqing Dazu District Kaiyuan Agriculture Co., Ltd. and other large-scale breeding farms for further expansion and breeding. At the same time, the production performance of the offspring individuals is measured, and the individuals that do not meet the breeding goals are eliminated; the selected part with production performance better than the parents is added to the basic group to further improve the production performance of the new breed. Finally, a new breed of high-breeding black goats with stable performance is bred (no less than 3,000).
[0034] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0035] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.
Claims
1. A method for breeding a new high-fertility strain of Dazu black goats, characterized in that: The steps include: S1, basic group formation, using genomic selection technology to select individuals with fast growth rate and high fertility to form the Dazu black goat breeding family, collect blood samples for SNP detection, and establish pedigree files; S2, closed breeding, which starts with the selection of the basic group, then closes the herd, and conducts corresponding selection and matching in the closed small group based on production performance, body shape and appearance, and pedigree source; S3, expansion and improvement, use genetic evaluation models to evaluate the genetic stability of goat high-yield traits and the molecular genetic stability of new breed groups, implement precise individual genetic evaluation of goats, and use cross-validation method to verify the accuracy of breeding values, and estimate the whole genome breeding values of the established breeding group.
2. The method for breeding a high-fertilization new strain of Dazu black goats according to claim 1, characterized in that: In step S1, individuals that meet the requirements of high reproduction and fast growth are selected as the breeding base group (more than 800 ewes and 30 rams); The high reproduction rate is: the multiparous ewe gives birth to two consecutive litters, with an average number of live lambs per litter of ≥2.7; the ram's ejaculation volume is ≥0.70mL, the sperm motility is ≥90%, and the conception rate with the mating ewe is ≥270%; The rapid growth: the weight of the ewe reaches more than 18.5kg at 6 months old, and the weight at one year old reaches more than 27kg; the weight of the ram reaches more than 21.5kg at 6 months old, and the weight at one year old reaches more than 31kg.
3. The method for breeding a high-fertilization new strain of Dazu black goats according to claim 1, characterized in that: In step S2, 600 ewes and 20 rams are selected for each generation, and a random mating system is implemented to avoid full-sibling and half-sibling mating.
4. The method for breeding a high-fertilization new strain of Dazu black goats according to claim 1, characterized in that: Step S2, conducting closed breeding of the basic group for 4 generations without introducing foreign blood, so that the average inbreeding coefficient of the group naturally increases to 10% to 15%.
5. The method for breeding a high-fertilization new strain of Dazu black goats according to claim 1, characterized in that: Step S2, determine the lambing number and weight data of the sheep, and take blood from the jugular vein after marking, extract genomic DNA, use whole genome resequencing to perform SNP genotyping, and statistically calculate SNP effects; at the same time, establish a BLUP genetic evaluation system and model.
6. The method for breeding a high-fertilization new strain of Dazu black goats according to claim 1, characterized in that: Step S2, genes PSTPIP2, C7orf57, CDKAL1, CCL19, FGF9, SGCG, SIPA1L1, and FIGN were selected as candidate genes regulating body shape traits in goats; Genes ATP1, LRRC4C, SPCS2, XRRA1, CELF4, NTM, TMEM45B, ATE, and FGFR2 were selected as candidate genes regulating breast traits; Genes ENSCHIG00000017110, SLC9A8, GLRB, GRIA2, GASK1B and ENSCHIG0000002628 were selected as candidate genes regulating the trait of litter size.
7. The method for breeding a high-fertilization new strain of Dazu black goats according to claim 1, characterized in that: Step S3, grading the selected sheep flock according to the evaluation results of production performance, body shape and appearance, and the principle of grade selection is that the grade of rams is higher than that of ewes.