Breeding method of changfeng native chicken

Abstract

This invention relates to a breeding method for Changfeng native chickens. It involves selecting Sanhuang chickens and Ma chickens as maternal lines, and White Locke chickens and Cobb White-feathered chickens as paternal lines, and conducting directional hybridization using artificial insemination to form the F1 generation hybrid population. Next, based on the weight and meat quality test results at 300 days of age, superior families are selected, and the target traits are gradually fixed through multiple generations of directional hybridization and backcrossing. Simultaneously, genes from high-yielding broiler breeds such as Ross 308 or Cobb 500 are introduced to enhance the breeding performance of the paternal lines. Finally, through refined feeding management and a phased feeding strategy, the breeding effect is further optimized to ensure that the newly bred Changfeng native chicken breed reaches a weight of 3.0 to 3.5 kg at 300 days of age, with a breast muscle ratio of no less than 22%, and a stable egg production of over 170 eggs. This breeding method significantly increases the weight of Changfeng native chickens, while also making the meat firmer and improving its meat quality.

Description

[Technical Field]

[0001] This invention relates to the field of Changfeng native chicken breeding technology, and in particular to a method for breeding Changfeng native chickens. [Background Technology]

[0002] With the increasing demand from consumers for high-quality poultry products, the development of breeding technology has become a key factor in improving poultry production efficiency and product quality. In the field of poultry breeding, especially in the breeding of native chicken breeds, traditional breeding methods mainly rely on natural mating and selection. However, with the increasing market demand for high-quality native chicken breeds with local characteristics, traditional breeding methods have gradually shown their limitations, such as long breeding cycles, low yields, and unstable performance. Therefore, the application of modern breeding technology in native chicken breeding is becoming increasingly important.

[0003] Changfeng native chicken, a high-quality breed with unique flavor and local characteristics, has received widespread attention in recent years. It combines the excellent meat quality and disease resistance of local native chickens, making it particularly valuable in the poultry market of southern China. However, its slow growth rate and relatively low egg production limit its widespread application in large-scale farming. Therefore, improving the growth rate, meat quality, and egg production of Changfeng native chicken through modern breeding techniques has become a major challenge in breeding work.

[0004] To overcome the shortcomings of traditional breeding methods, many studies and practices in recent years have begun to apply modern breeding techniques to native chicken breeding. One effective method is to introduce genes from high-yielding broiler breeds and combine them with local breeds for crossbreeding. This method can significantly improve growth rate and egg production performance while maintaining the meat flavor of local breeds. Furthermore, precise breeding management and feeding strategies, such as artificial insemination, refined feeding management, and phased feeding strategies, are gradually becoming important tools in breeding. Slow growth rate: While traditional native chicken breeds have excellent meat quality, they generally suffer from slow growth rates. Generally, native chicken breeds tend to have lower body weights at 300 days of age, failing to meet the high-efficiency production requirements of modern agriculture. This results in long breeding cycles, high feeding costs, and an inability to compete with fast-growing broiler breeds. Currently, there are also problems such as low egg production. Native chicken breeds have relatively low egg production, and traditional breeding methods struggle to significantly improve egg production performance without affecting meat quality. This results in insufficient market supply and economic benefits for native chicken breeds, making it difficult to meet the market demand for high-quality laying hens. Unstable genetic traits: Traditional breeding methods rely heavily on natural mating and selection, making them highly susceptible to environmental factors. This leads to unstable genetic traits during the breeding process, resulting in significant differences in offspring performance. This uncertainty increases the difficulty of breeding and affects farmers' production plans and the stability of market supply. Lack of systematic breeding management: Traditional native chicken breeding often lacks systematic management. The selection criteria and methods used in the breeding process are not scientific enough, resulting in low breeding efficiency, long breeding cycles, and difficulty in quickly launching new varieties that meet market demands. [Summary of the Invention]

[0005] In view of the above, it is necessary to provide a breeding method for Changfeng native chickens, including the following steps: First, select Sanhuang chickens and Ma chickens as maternal lines (SD1, SD2), and select White Locke chickens and Cobb White Feather chickens as paternal lines (HS1, HS2), and conduct directional hybridization through artificial insemination to form the F1 generation hybrid population; next, select superior families based on the body weight and meat quality test results at 300 days of age, and gradually fix the target traits through multiple generations of directional hybridization and backcrossing; simultaneously, introduce genes from high-yielding foreign broiler breeds such as Ross 308 or Cobb 500 to enhance the breeding performance of the paternal lines; finally, further optimize the breeding effect through refined feeding management and a phased feeding strategy to ensure that the newly bred Changfeng native chicken breed reaches a body weight of 3.0 to 3.5 kg at 300 days of age, with a breast muscle ratio of no less than 22%, and a stable egg production of more than 170 eggs. This breeding method improves the production efficiency and market competitiveness of Changfeng native chickens and has broad application prospects. It can significantly increase the weight of Changfeng native chicken while reducing its fat content, making the meat firmer and improving its quality.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A method for breeding Changfeng native chickens includes the following steps:

[0008] a) Using Sanhuang chickens and Ma chickens as maternal lines (SD1, SD2), their weight should be between 2.5 and 3.0 kg at 300 days of age, and their egg production should be no less than 150 eggs at 300 days of age; using White Rock chickens and Cobb White-feathered chickens as paternal lines (HS1, HS2), their weight should reach 3.5 to 4.0 kg at 300 days of age under standard feeding conditions, and their breast muscle should account for no less than 20% of their body weight.

[0009] b) Using artificial insemination, the selected maternal line SD1 and paternal line HS1 were crossbred in a directional manner, and the maternal line SD2 and paternal line HS2 were crossbred in a directional manner to obtain two independent F1 generation hybrid populations. From the F1 generation hybrid populations, 60 families were selected as the first generation core group based on the body weight at 300 days of age and the meat quality test results. Individuals in the core group had a body weight of not less than 3.0 kg at 300 days of age, and the meat quality test showed that the content of unsaturated fatty acids in the muscle was not less than 30%.

[0010] c) The superior individuals in the first-generation core population of SD1×HS1 are backcrossed with the maternal line SD1 again, and the superior individuals in the first-generation core population of SD2×HS2 are backcrossed with the maternal line SD2 again to form the F2 generation; in the F2 generation, based on the body weight at 300 days of age and the egg production at 300 days of age, families with excellent growth rate and egg production performance are selected as the second-generation core population, ensuring that the body weight of individuals in the core population at 300 days of age is not less than 3.2 kg and the egg production is not less than 160 eggs;

[0011] d) Through multiple generations of directional hybridization and backcrossing, the target traits are gradually fixed, and families with high growth rate, excellent meat quality and high egg production performance are selected. Each generation is screened based on body weight at 300 days of age, pectoral muscle ratio and egg production. The screening criteria are: body weight at 300 days of age not less than 3.2 kg, pectoral muscle ratio not less than 22% of body weight, and egg production not less than 170 eggs.

[0012] e) Combine and finalize the Changfeng native chickens that are finally bred. Use the fixed combination offspring of SD1×HS1 and SD2×HS2 as Changfeng native chickens. The weight of the combined offspring at 300 days of age is between 3.0 and 3.5 kg, the proportion of breast muscle reaches more than 22%, and the egg production is stable at more than 170 eggs.

[0013] Furthermore, in step a), the feathers of the Sanhuang chicken are pure yellow, and its beak and legs are yellow, without any spots or color differences; the feathers of the Ma chicken are brownish-yellow, and its beak and legs are yellow.

[0014] Furthermore, the White Rock chickens and Cobb White-feathered chickens should weigh 3.5 to 4.0 kg at 300 days of age, with breast muscle accounting for no less than 20% of their body weight.

[0015] Furthermore, the volume of semen used for each hen during artificial insemination is 0.1 ml to 0.2 ml. After insemination, the fertilization rate of the hens is checked within 5 days. The development of the fertilized eggs is determined by ovarian ultrasound. The fertilization rate is required to reach more than 95% to ensure the high efficiency of the hybridization process and the excellent genetic characteristics of the offspring.

[0016] Furthermore, in step b), 60 families are selected from the F1 generation hybrid population. The feather color of individuals in each family should be consistent with that of the maternal line. The feathers of the Sanhuang chicken family are pure yellow, and the feathers of the Ma chicken family are brownish-yellow. Each individual should weigh more than 3.0 kg at 300 days of age.

[0017] Furthermore, during the backcrossing process in step c), the selected maternal individuals must lay no less than 160 eggs at 300 days of age, with light brown eggshells and a shell thickness of 0.35 mm to 0.40 mm.

[0018] Furthermore, in the multi-generational selection process in step d), the individuals selected in each generation shall have a weight of not less than 3.2 kg at 300 days of age, and the weight of the pectoral muscles shall account for not less than 22% of the body weight.

[0019] Furthermore, during the screening process in step d), the feed conversion ratio of each selected individual should not exceed 2.5, that is, every 2.5 kg of feed should be converted into at least 1 kg of body weight gain.

[0020] Furthermore, in step a), the selection of the paternal lines HS1 and HS2 further includes introducing genes from foreign high-yielding broiler breeds Ross 308 or Cobb 500 through hybridization. Specifically, the grandparent paternal line of Ross 308 is first hybridized with White Rock chickens to form an enhanced HS1 paternal line; the grandparent maternal line of Cobb 500 is hybridized with Cobb White-feathered chickens to form an enhanced HS2 paternal line; after hybridization, individuals with a weight of 3.5 to 4.0 kg and a breast muscle weight accounting for no less than 22% of the body weight are selected from the hybrid offspring as the enhanced HS1 and HS2 paternal lines, which are then used for subsequent hybridization steps with Sanhuang chickens and Ma chickens.

[0021] Furthermore, in the breeding process of HS1 and HS2 paternal lines after introducing genes from high-yielding foreign broiler breeds such as Ross 308 or Cobb 500 through hybridization, the ratio of protein and energy in the feed formulation is controlled. Specifically, the crude protein content in the feed is 20% to 22%, and the metabolizable energy is 11.5 to 12.5 MJ / kg. Simultaneously, a staged feeding strategy is adopted, increasing the proportion of high-energy feeds such as corn and soybean meal during the fattening stage to ensure a weight gain of no less than 45 grams per day during the fattening period.

[0022] The present invention has the following beneficial effects:

[0023] 1. Significantly Improved Growth Rate: By selecting superior paternal lines (White Locker chicken, Cobb White-feathered chicken) and introducing genes from high-yielding broiler breeds such as Ross 308 or Cobb 500, this invention significantly improves the growth rate of Changfeng native chickens. The resulting Changfeng native chickens can reach a weight of 3.0 to 3.5 kg at 300 days of age, meeting the modern market demand for fast-growing broilers, shortening the breeding cycle, and improving production efficiency.

[0024] 2. Optimization of meat quality and egg production performance: This invention, while retaining the excellent meat quality characteristics of the maternal lines (Sanhuang chicken and Ma chicken), gradually stabilized a family line with excellent meat quality and high egg production performance through multiple generations of targeted hybridization and backcrossing. The Changfeng native chickens finally bred have a breast muscle ratio of no less than 22% at 300 days of age, while the egg production is stable at more than 170 eggs, achieving dual optimization of meat quality and egg production performance.

[0025] 3. Optimized genetic stability and high-quality meat: This invention employs a multi-generational directional hybridization and backcrossing breeding method to gradually fix the superior traits of Changfeng native chickens. Each generation incorporates strict selection criteria, particularly regarding body weight at 300 days of age, breast muscle ratio, and egg production performance, ultimately resulting in a new Changfeng native chicken strain exhibiting high stability in genetic traits. Through this selection and breeding method, this invention successfully optimizes meat quality, significantly increasing the unsaturated fatty acid content in the muscle and achieving a breast muscle ratio of over 22% of body weight. This optimized meat quality meets market demand for high-quality chicken and significantly enhances the market competitiveness of Changfeng native chickens.

[0026] 4. High-efficiency growth and egg production performance: In the breeding process of this invention, by introducing the superior genes of White Locker, Cobb White-feathered Chicken, and Ross 308 or Cobb 500, and combining them with the superior traits of Sanhuang Chicken and Ma Chicken, a balance between high-efficiency growth and high egg production is achieved. The newly bred Changfeng native chicken breed can reach a weight of 3.0 to 3.5 kg at 300 days of age, while maintaining a stable egg production of over 170 eggs. This high-efficiency growth and egg production performance is particularly beneficial for large-scale farming, not only shortening the breeding cycle but also significantly improving the economic benefits for farmers.

[0027] 5. Establishment and Optimization of Comprehensive Selection Indicators: In the breeding process, this invention establishes comprehensive selection indicators centered on body weight, egg production, and pectoral muscle ratio, combined with appearance traits (such as feather color and shank color) for comprehensive screening. Through this systematic selection and screening mechanism, a group of core families meeting the target traits has been successfully selected, and these traits have been further optimized and consolidated through subsequent generations of breeding. This comprehensive selection method effectively ensures that the selected individuals in each generation possess ideal growth and production performance, avoiding the shortcomings of unstable traits in traditional breeding.

Detailed Implementation Methods

[0028] All features disclosed in this specification, or all steps in all disclosed methods or processes, may be combined in any way, except for mutually exclusive features and / or steps.

[0029] Unless otherwise stated, each feature disclosed in this specification (including any appended claims and abstract) is merely one example of a series of equivalent or similar features. The reagents, raw materials, probiotics, etc., used in this invention are all commercially available.

[0030] Example 1:

[0031] In this embodiment, a method for breeding Changfeng native chickens includes the following steps:

[0032] a) Using Sanhuang chickens and Ma chickens as maternal lines (SD1, SD2), their weight should be between 2.5 and 3.0 kg at 300 days of age, and their egg production should be no less than 150 eggs at 300 days of age; using White Rock chickens and Cobb White-feathered chickens as paternal lines (HS1, HS2), their weight should reach 3.5 to 4.0 kg at 300 days of age under standard feeding conditions, and their breast muscle should account for no less than 20% of their body weight.

[0033] For the selection and breeding of maternal lines, this example uses Sanhuang chickens and Ma chickens as maternal lines (labeled SD1 and SD2 respectively). Sanhuang and Ma chickens are high-quality local chicken breeds widely raised in southern China, favored by farmers for their excellent meat quality and egg production performance. Maternal line performance requirements: To ensure breeding effectiveness, the selected maternal lines must meet the following conditions at 300 days of age: Weight: 2.5 to 3.0 kg. By controlling stocking density, feed formulation, and lighting conditions, the maternal lines are guaranteed to reach the ideal weight range at 300 days of age. Egg production: No less than 150 eggs at 300 days of age. By regularly monitoring the egg production of the maternal lines, individuals meeting the egg production standards are selected to ensure high maternal productivity.

[0034] Selection and breeding of sires: In this example, the White Rock chicken and Cobb White-feathered chicken were selected as sires (labeled HS1 and HS2 respectively). White Rock and Cobb White-feathered chickens are known for their rapid growth and high meat quality, making them suitable as sires for crossbreeding. Sire performance requirements: Under standard feeding conditions, the sires should meet the following conditions at 300 days of age: Weight: 3.5 to 4.0 kg. Through proper feeding management, including the use of high-protein and high-energy feeds, ensure that the sires reach the target weight at 300 days of age. Breast muscle ratio: Breast muscle weight should account for no less than 20% of body weight. Breast muscle mass was measured in the sires, and individuals meeting the standards were selected to ensure the superior meat quality of the offspring.

[0035] Hybridization and F1 generation selection: Hybridization process: Artificial insemination was used to selectively cross the maternal line SD1 with the paternal line HS1, and the maternal line SD2 with the paternal line HS2, resulting in two independent F1 hybrid populations. During artificial insemination, 0.1 to 0.2 ml of semen was used per hen to ensure a fertilization rate of over 95%. F1 generation selection: From the F1 hybrid population, families meeting the following criteria were selected as the core group for the first generation: Weight at 300 days of age not less than 3.0 kg; Meat quality testing showing an unsaturated fatty acid content of not less than 30% in the muscle. Superior families were selected through regular monitoring of weight and meat quality.

[0036] Breeding, backcrossing, and selection of F2 generation and subsequent generations: Superior individuals from the first-generation core population of SD1×HS1 are backcrossed with the maternal line SD1 again; superior individuals from the first-generation core population of SD2×HS2 are backcrossed with the maternal line SD2 again, forming the F2 generation. F2 generation selection: The second-generation core population is selected according to the following criteria: body weight at 300 days of age not less than 3.2 kg; egg production at 300 days of age not less than 160 eggs. Multiple selections are conducted for each generation of the F2 population to fix the target traits and make the offspring performance more stable. Multi-generation directional hybridization and trait fixation: Through multi-generation directional hybridization and backcrossing, the target traits of high growth rate, excellent meat quality, and high egg production performance are gradually fixed. Each generation is selected based on body weight at 300 days of age, pectoral muscle ratio, and egg production to ensure that the selected individuals meet these performance indicators.

[0037] The final combination and shaping were achieved by repeatedly crossing the offspring of fixed combinations of SD1×HS1 and SD2×HS2 to develop the final new Changfeng native chicken breed. After performance testing at 300 days of age, it was determined that the final Changfeng native chicken breed had a weight between 3.0 and 3.5 kg, a breast muscle ratio of over 22%, and a stable egg production of over 170 eggs.

[0038] b) Using artificial insemination, the selected maternal line SD1 and paternal line HS1 were crossbred in a directional manner, and the maternal line SD2 and paternal line HS2 were crossbred in a directional manner to obtain two independent F1 generation hybrid populations. From the F1 generation hybrid populations, 60 families were selected as the first generation core group based on the body weight at 300 days of age and the meat quality test results. Individuals in the core group had a body weight of not less than 3.0 kg at 300 days of age, and the meat quality test showed that the content of unsaturated fatty acids in the muscle was not less than 30%.

[0039] In one embodiment, semen collection and processing: Semen was collected from both HS1 and HS2 paternal lines and diluted to a suitable concentration using a diluent. The amount used for insemination was 0.15 ml per hen. Artificial insemination: Artificial insemination was performed on maternal lines SD1 and SD2, ensuring each hen was in optimal physiological condition at the time of insemination. The insemination process lasted for one week, with insemination twice daily. Formation of the F1 generation: Within 21 days of insemination, F1 hybrid population 1 (SD1×HS1) and F1 hybrid population 2 (SD2×HS2) were hatched. Each population contained approximately 300 individuals. Weight measurement at 300 days of age: All individuals in both F1 hybrid populations were weighed at 300 days of age. Individuals weighing at least 3.0 kg were selected for the next screening step. Meat quality testing: Meat quality testing was performed on individuals meeting the weight standard, with particular attention paid to the content of unsaturated fatty acids in the muscle. The proportion of unsaturated fatty acids in each sample was determined using gas chromatography, and individuals with an unsaturated fatty acid content of at least 30% in muscle were selected. Establishment of the core population: From two F1 generation hybrid populations, 30 families were selected from each, for a total of 60 families. Individuals in these families met the weight and meat quality standards at 300 days of age. These families were designated as the first-generation core population for subsequent breeding work.

[0040] c) The superior individuals in the first-generation core population of SD1×HS1 are backcrossed with the maternal line SD1 again, and the superior individuals in the first-generation core population of SD2×HS2 are backcrossed with the maternal line SD2 again to form the F2 generation; in the F2 generation, based on the body weight at 300 days of age and the egg production at 300 days of age, families with excellent growth rate and egg production performance are selected as the second-generation core population, ensuring that the body weight of individuals in the core population at 300 days of age is not less than 3.2 kg and the egg production is not less than 160 eggs;

[0041] d) Through multiple generations of directional hybridization and backcrossing, the target traits are gradually fixed, and families with high growth rate, excellent meat quality and high egg production performance are selected. Each generation is screened based on body weight at 300 days of age, pectoral muscle ratio and egg production. The screening criteria are: body weight at 300 days of age not less than 3.2 kg, pectoral muscle ratio not less than 22% of body weight, and egg production not less than 170 eggs.

[0042] e) Combine and finalize the Changfeng native chickens that are finally bred. Use the fixed combination offspring of SD1×HS1 and SD2×HS2 as Changfeng native chickens. The weight of the combined offspring at 300 days of age is between 3.0 and 3.5 kg, the proportion of breast muscle reaches more than 22%, and the egg production is stable at more than 170 eggs.

[0043] In one embodiment, in step a), the feathers of the Sanhuang chicken are pure yellow, and its beak and legs are yellow, without spots or color differences; the feathers of the Ma chicken are brownish-yellow, and its beak and legs are yellow.

[0044] In one embodiment, the White Rock chicken and Cobb White-feathered chicken should weigh 3.5 to 4.0 kg at 300 days of age, and the breast muscle weight should account for no less than 20% of the body weight.

[0045] Furthermore, the volume of semen used for each hen during artificial insemination is 0.1 ml to 0.2 ml. After insemination, the fertilization rate of the hens is checked within 5 days. The development of the fertilized eggs is determined by ovarian ultrasound. The fertilization rate is required to reach more than 95% to ensure the high efficiency of the hybridization process and the excellent genetic characteristics of the offspring.

[0046] Furthermore, in step b), 60 families are selected from the F1 generation hybrid population. The feather color of individuals in each family should be consistent with that of the maternal line. The feathers of the Sanhuang chicken family are pure yellow, and the feathers of the Ma chicken family are brownish-yellow. Each individual should weigh more than 3.0 kg at 300 days of age.

[0047] Furthermore, during the backcrossing process in step c), the selected maternal individuals must lay no less than 160 eggs at 300 days of age, with light brown eggshells and a shell thickness of 0.35 mm to 0.40 mm.

[0048] Furthermore, in the multi-generational selection process in step d), the individuals selected in each generation shall have a weight of not less than 3.2 kg at 300 days of age, and the weight of the pectoral muscles shall account for not less than 22% of the body weight.

[0049] Furthermore, during the screening process in step d), the feed conversion ratio of each selected individual should not exceed 2.5, that is, every 2.5 kg of feed should be converted into at least 1 kg of body weight gain.

[0050] Example 2:

[0051] Furthermore, in step a), the selection of the paternal lines HS1 and HS2 further includes introducing genes from foreign high-yielding broiler breeds Ross 308 or Cobb 500 through hybridization. Specifically, the grandparent paternal line of Ross 308 is first hybridized with White Rock chickens to form an enhanced HS1 paternal line; the grandparent maternal line of Cobb 500 is hybridized with Cobb White-feathered chickens to form an enhanced HS2 paternal line; after hybridization, individuals with a weight of 3.5 to 4.0 kg and a breast muscle weight accounting for no less than 22% of the body weight are selected from the hybrid offspring as the enhanced HS1 and HS2 paternal lines, which are then used for subsequent hybridization steps with Sanhuang chickens and Ma chickens.

[0052] Furthermore, in the breeding process of HS1 and HS2 paternal lines after introducing genes from foreign high-yield broiler breeds Ross 308 or Cobb 500 through hybridization, the ratio of protein and energy in the feed formula is controlled. Specifically, the crude protein content in the feed is 20% to 22%, and the metabolizable energy is 11.5 to 12.5 MJ / kg. At the same time, a staged feeding strategy is adopted, increasing the proportion of high-energy feeds such as corn and soybean meal in the fattening stage to ensure that the weight gain rate during the fattening period is not less than 45 grams / day.

[0053] Table 1 records the body weight and breast muscle ratio of chickens at 300 days of age in flocks with and without introduced high-yield genes (Ross 308 and Cobb 500). Data for each group comes from three different chickens, providing mean values ​​and inter-sample variability. Groups: Different experimental groups were distinguished, including those with "Ross 308 gene introduced," "no gene introduced," and "Cobb 500 gene introduced," as well as corresponding control groups. Chicken Number: Each chicken was assigned a number (1-3) to ensure data traceability. Body Weight at 300 Days of Age (kg): The body weight of each chicken was measured at 300 days of age. Chicken flocks introduced with the Ross 308 gene exhibited higher average weights, around 3.7 kg, while flocks introduced with the Cobb 500 gene averaged around 3.8 kg, and flocks without the gene introduction weighed between 3.2 and 3.3 kg. This data demonstrates the positive impact of gene introduction on chicken weight gain. Breast muscle weight as a percentage of body weight (%): The percentage of breast muscle weight per chicken was recorded. Chickens with the introduced gene had a higher breast muscle percentage, reaching around 23%, while the percentage in flocks without the gene was around 20%. This indicates that introducing high-yield genes effectively improved breast muscle development in chickens, significantly enhancing meat quality performance.

[0054] Table 1 Comparison of Body Weight and Chest Muscle Ratio

[0055] Group Chicken Number Weight at 300 days old (kg) Pectoral muscle weight as a percentage of body weight (%) Introducing the Ross 308 gene 1 3.7 23 Introducing the Ross 308 gene 2 3.6 22.5 Introducing the Ross 308 gene 3 3.8 23.2 No genes introduced 1 3.2 20 No genes introduced 2 3.3 20.5 No genes introduced 3 3.1 19.8 Introducing the Kobo 500 gene 1 3.8 22.5 Introducing the Kobo 500 gene 2 3.7 22.8 Introducing the Kobo 500 gene 3 3.9 23 No genes introduced 1 3.3 20.5 No genes introduced 2 3.2 20 No genes introduced 3 3.1 19.9

[0056] Table 2 presents data on average daily weight gain and feed conversion ratio (FCR) of chicken flocks during the fattening period (typically the fastest growth phase). Each data set is based on measurements from three chickens and covers key growth indicators during the fattening period. Detailed descriptions of data items: The experimental and control groups were distinguished by the introduction of the Ross 308 gene, no gene introduction, and the introduction of the Cobb 500 gene. Chicken number: The chicken's number (1-3). Average daily weight gain (g / day): Recorded the average daily weight gain of each chicken during the fattening period. The average daily weight gain of the gene-introduced flock was 47-48 grams, while that of the non-gene-introduced flock was 40-41 grams. The growth rate of the gene-introduced flock was significantly better than that of the non-gene-introduced flock. Feed conversion ratio: Feed conversion ratio refers to the amount of feed required to gain 1 kg of body weight. The feed conversion ratio of the gene-introduced flock was 1.9-2.0, while that of the non-gene-introduced flock was poorer, at 2.3-2.4. A lower feed conversion ratio means higher feed utilization efficiency, which is an important indicator for improving farming efficiency.

[0057] Table 2: Comparison of Growth Rates (Fattening Period)

[0058]

[0059]

[0060] This table records the age at first egg production, initial weight, and egg production at 300 days of age for each flock, assessing the impact of introduced genes on flock egg production performance. Data were obtained from three chickens in each group (numbered 1-3). Detailed descriptions of data items: Group: Distinguishing between experimental and control groups, including "Introduced Ross 308 gene," "No gene introduced," and "Introduced Cobb 500 gene." Chicken Number: The chicken's number (1-3). Age at First Egg Production (days): Records the age at first egg production for each chicken. The flock with introduced genes started laying earlier (169-171 days), while the flock without introduced genes started laying later (175-176 days). This indicates that introducing high-producing genes can induce the flock to enter the laying period earlier, thereby increasing the total egg production over the laying cycle. Initial Weight at First Egg Production (kg): Records the weight of each chicken at the time of its first egg production. The chickens with the introduced gene had a higher body weight at the start of egg production (2.0-2.1 kg), while the chickens without the introduced gene had a lower body weight at the start of egg production (1.8-1.9 kg). This demonstrates the promoting effect of gene introduction on early growth and weight accumulation in the flock. Egg production at 300 days of age: The cumulative egg production per chicken at 300 days of age was recorded. The egg production of the chickens with the introduced gene was significantly higher than that of the control group (175-178 eggs vs. 160-165 eggs), indicating that gene introduction not only accelerated the start of egg production but also increased the total egg production.

[0061] Table 3: Comparison of Egg Production Performance

[0062]

[0063]

[0064] This table covers data on the content of unsaturated fatty acids and muscle fiber density in chicken muscle, assessing the impact of introducing a high-yield gene on meat health and quality. Each data set is based on measurements from samples of three chickens (numbered 1-3). Detailed descriptions of data items: Group: Distinguishing between experimental and control groups, including "Introduced Ross 308 gene," "No gene introduced," and "Introduced Cobb 500 gene." Chicken Number: The number of each chicken (1-3). Unsaturated Fatty Acid Content in Muscle (%): Records the proportion of unsaturated fatty acids in the muscle of each chicken. Chickens with the introduced gene had higher unsaturated fatty acid content (32-33%), while those without the introduced gene had lower content (29-30%). Unsaturated fatty acids have a significant impact on the taste and health of meat, demonstrating the significant effect of gene introduction in improving meat health. Muscle Fiber Density (fibers / mm²): Records the muscle fiber density of each chicken. Chicken flocks with the introduced gene had a higher muscle fiber density (450-460 fibers / mm²), while flocks without the introduced gene had a lower density (400-410 fibers / mm²). Higher muscle fiber density usually means more tender meat and better taste, indicating that the introduction of high-yield genes has a significant effect on improving meat quality.

[0065] Table 4: Comparison of Meat Quality Testing

[0066]

[0067] Example 3:

[0068] The following table records the weight gain of chickens from different generations (F1 and F2) and the control group at different ages. The data covers weight performance at 1 week, 4 weeks, 8 weeks, 13 weeks, and 22 weeks of age, and distinguishes between growth data for roosters and hens.

[0069] Table 5: Weight Gain Data Table

[0070]

[0071] F1 and F2 generations: By introducing superior paternal and maternal lines, the F2 generation surpassed the F1 generation in weight gain at all ages, demonstrating a gradual improvement in breeding effectiveness.

[0072] Control group: The control group (local chickens that have not undergone breeding optimization) had lower body weights at all ages than the F1 and F2 generations, especially at 22 weeks of age, where the control group's body weight was significantly lower than that of the F2 generation. This indicates that modern breeding methods have significantly improved the growth rate of Changfeng native chickens.

[0073] Table 6 records the age at first laying, body weight at first laying, egg weight at first laying, body weight at 300 days of age, and egg production at 300 days of age for different generations of chickens. These data reflect the key performance indicators of chickens during their production period.

[0074] Table 6: Egg Production Performance Data Table

[0075]

[0076] Age at first laying and weight at first laying: The F2 generation showed better performance in terms of age at first laying and weight at first laying than the F1 generation, demonstrating the effective optimization of growth rate and early egg production performance during the breeding process.

[0077] Body weight and egg production at 300 days of age: The body weight and egg production of the F2 generation at 300 days of age were higher than those of the control group, further demonstrating that the breeding strategy significantly improved the egg production performance and weight gain of Changfeng native chickens.

[0078] Table 7 shows the semi-eviscerated yield, fully eviscerated yield, breast muscle percentage, leg muscle percentage, and carcass weight of chickens from different generations. These indicators directly reflect the quality of the chicken meat.

[0079] Table 7: Meat Quality Characteristics Data Table

[0080]

[0081]

[0082] Breast and leg muscle percentages: The breast and leg muscle percentages of the F2 generation were higher than those of the F1 generation and the control group, indicating that the meat quality characteristics were successfully enhanced during the breeding process, especially the breast muscle, which has an important impact on the taste and nutritional value of the meat.

[0083] Carcass weight: The carcass weight of the F2 generation was higher than that of the control group, indicating that the breeding method was effective in increasing chicken yield.

[0084] Table 8 shows the feed conversion ratio data, which reflects the feed utilization efficiency of different generations of chickens at various growth stages. The feed conversion ratios were recorded at 1 week, 4 weeks, 8 weeks, 13 weeks, and 22 weeks of age.

[0085] Table 8: Feed Conversion Rate Data Table

[0086]

[0087] Feed conversion efficiency: The F2 generation showed better feed conversion rates than the F1 generation and the control group at all stages, especially in the fattening stages (13 weeks and 22 weeks), where the F2 generation had the lowest feed conversion rate, demonstrating higher feed utilization efficiency. This means that by optimizing breeding, more meat can be produced with the same feed consumption, reducing farming costs.

[0088] Table 9 records key performance indicators such as weight gain rate, feed conversion ratio, body weight at 300 days, and egg production at 300 days for different generations of chickens under different rearing environments (standard rearing and high temperature and humidity).

[0089] Table 9: Growth Performance Data under Different Feeding Environments

[0090]

[0091] Environmental adaptability: The F2 generation maintained high growth rates and egg production even under high temperature and humidity conditions, demonstrating that the breeding process not only optimized growth and egg production performance but also improved environmental adaptability. This is of great significance for farmers in production under changing environments.

[0092] The control group showed a significant decrease in weight gain and egg production performance in the high temperature and humidity environment, further highlighting the superiority of the breeding method of this invention in improving the environmental adaptability of Changfeng native chickens.

[0093] The present invention has the following beneficial effects:

[0094] 1. Significantly Improved Growth Rate: By selecting superior paternal lines (White Locker chicken, Cobb White-feathered chicken) and introducing genes from high-yielding broiler breeds such as Ross 308 or Cobb 500, this invention significantly improves the growth rate of Changfeng native chickens. The resulting Changfeng native chickens can reach a weight of 3.0 to 3.5 kg at 300 days of age, meeting the modern market demand for fast-growing broilers, shortening the breeding cycle, and improving production efficiency.

[0095] 2. Optimization of meat quality and egg production performance: This invention, while retaining the excellent meat quality characteristics of the maternal lines (Sanhuang chicken and Ma chicken), gradually stabilized a family line with excellent meat quality and high egg production performance through multiple generations of targeted hybridization and backcrossing. The Changfeng native chickens finally bred have a breast muscle ratio of no less than 22% at 300 days of age, while the egg production is stable at more than 170 eggs, achieving dual optimization of meat quality and egg production performance.

[0096] 3. Optimized genetic stability and high-quality meat: This invention employs a multi-generational directional hybridization and backcrossing breeding method to gradually fix the superior traits of Changfeng native chickens. Each generation incorporates strict selection criteria, particularly regarding body weight at 300 days of age, breast muscle ratio, and egg production performance, ultimately resulting in a new Changfeng native chicken strain exhibiting high stability in genetic traits. Through this selection and breeding method, this invention successfully optimizes meat quality, significantly increasing the unsaturated fatty acid content in the muscle and achieving a breast muscle ratio of over 22% of body weight. This optimized meat quality meets market demand for high-quality chicken and significantly enhances the market competitiveness of Changfeng native chickens.

[0097] 4. High-efficiency growth and egg production performance: In the breeding process of this invention, by introducing the superior genes of White Locker, Cobb White-feathered Chicken, and Ross 308 or Cobb 500, and combining them with the superior traits of Sanhuang Chicken and Ma Chicken, a balance between high-efficiency growth and high egg production is achieved. The newly bred Changfeng native chicken breed can reach a weight of 3.0 to 3.5 kg at 300 days of age, while maintaining a stable egg production of over 170 eggs. This high-efficiency growth and egg production performance is particularly beneficial for large-scale farming, not only shortening the breeding cycle but also significantly improving the economic benefits for farmers.

[0098] 5. Establishment and Optimization of Comprehensive Selection Indicators: In the breeding process, this invention establishes comprehensive selection indicators centered on body weight, egg production, and pectoral muscle ratio, combined with appearance traits (such as feather color and shank color) for comprehensive screening. Through this systematic selection and screening mechanism, a group of core families meeting the target traits has been successfully selected, and these traits have been further optimized and consolidated through subsequent generations of breeding. This comprehensive selection method effectively ensures that the selected individuals in each generation possess ideal growth and production performance, avoiding the shortcomings of unstable traits in traditional breeding.

[0099] The applicant declares that the above-described embodiments illustrate the products, uses, and methods of use of the present invention; however, the present invention is not limited to the detailed uses or methods of use described above, i.e., it does not mean that the present invention must rely on the detailed uses and methods of use described above to be realized. Those skilled in the art should understand that any improvements to the present invention, equivalent substitutions of the raw materials of the product of the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A method for breeding Changfeng native chickens, characterized in that, Includes the following steps: a) Using Sanhuang chickens and Ma chickens as maternal lines (SD1, SD2), their weight should be between 2.5 and 3.0 kg at 300 days of age, and their egg production should be no less than 150 eggs at 300 days of age; using White Rock chickens and Cobb White-feathered chickens as paternal lines (HS1, HS2), their weight should reach 3.5 to 4.0 kg at 300 days of age under standard feeding conditions, and their breast muscle should account for no less than 20% of their body weight; in step a), the selection of the paternal lines HS1 and HS2 further includes introducing high-yielding broiler chickens from abroad through hybridization. The specific method for obtaining genes from the Ross 308 or Cobb 500 breeds is as follows: First, the grandparent paternal parent of Ross 308 is crossed with the White Rock chicken to form an enhanced HS1 paternal line; the grandparent maternal parent of Cobb 500 is crossed with the Cobb White-feathered chicken to form an enhanced HS2 paternal line; after hybridization, individuals with a weight of 3.5 to 4.0 kg and a breast muscle weight of not less than 22% of body weight are selected from the hybrid offspring to serve as the enhanced HS1 and HS2 paternal lines, which are then used for subsequent hybridization steps with Sanhuang chickens and Ma chickens; In the breeding process of HS1 and HS2 paternal lines after introducing genes from high-yielding foreign broiler breeds Ross 308 or Cobb 500 through hybridization, the ratio of protein and energy in the feed formula is controlled. Specifically, the crude protein content in the feed is 20% to 22%, and the metabolizable energy is 11.5 to 12.5 MJ / kg. At the same time, a staged feeding strategy is adopted, increasing the proportion of high-energy feeds such as corn and soybean meal in the fattening stage to ensure that the weight gain rate during the fattening period is not less than 45 grams / day. b) Using artificial insemination, the selected maternal line SD1 was crossbred with the paternal line HS1, and simultaneously, the maternal line SD2 was crossbred with the paternal line HS2, to obtain two independent F1 generation hybrid populations. From the F1 generation hybrid populations, based on the body weight at 300 days of age and meat quality test results, 60 families were selected as the core population of the first generation. Individuals in the core population had a body weight of not less than 3.0 kg at 300 days of age, and meat quality test results showed that the content of unsaturated fatty acids in the muscle was not less than 30%. c) The superior individuals in the first generation core group of SD1×HS1 are backcrossed with the maternal line SD1 again, and the superior individuals in the first generation core group of SD2×HS2 are backcrossed with the maternal line SD2 again to form the F2 generation; in the F2 generation, based on the body weight at 300 days of age and the egg production at 300 days of age, families with excellent growth rate and egg production performance are selected as the second generation core group, ensuring that the body weight of individuals in the core group is not less than 3.2 kg at 300 days of age and the egg production is not less than 160 eggs; d) Through multiple generations of directional hybridization and backcrossing, the target traits are gradually fixed, and families with high growth rate, excellent meat quality and high egg production performance are selected. Each generation is screened based on body weight at 300 days of age, pectoral muscle ratio and egg production. The screening criteria are: body weight at 300 days of age not less than 3.2 kg, pectoral muscle ratio not less than 22% of body weight, and egg production not less than 170 eggs. During the screening process in step d), the feed conversion ratio of individuals selected in each generation should not be higher than 2.5, that is, every 2.5 kg of feed should be converted into at least 1 kg of body weight gain. e) Combine and finalize the Changfeng native chickens that are finally bred. Use the fixed combination offspring of SD1×HS1 and SD2×HS2 as Changfeng native chickens. The weight of the combination offspring at 300 days of age is between 3.0 and 3.5 kg, the proportion of breast muscle reaches more than 22%, and the egg production is stable at more than 170 eggs.

2. The method for breeding Changfeng native chickens according to claim 1, characterized in that, In step a), the feathers of the Sanhuang chicken are pure yellow, and its beak and legs are yellow, without any spots or color differences; the feathers of the Ma chicken are brownish-yellow, and its beak and legs are yellow.

3. The method for breeding Changfeng native chickens according to claim 1, characterized in that, The White Rock chickens and Cobb White-feathered chickens should weigh 3.5 to 4.0 kg at 300 days of age, with breast muscle accounting for no less than 20% of their body weight.

4. The method for breeding Changfeng native chickens according to claim 1, characterized in that, During artificial insemination, the volume of semen used per hen is 0.1 ml to 0.2 ml. After insemination, the fertilization rate of the hens is checked within 5 days. The development of the fertilized eggs is determined by ovarian ultrasound. The fertilization rate is required to reach more than 95% to ensure the high efficiency of the hybridization process and the excellent genetic characteristics of the offspring.

5. The method for breeding Changfeng native chickens according to claim 1, characterized in that, In step b), 60 families are selected from the F1 generation hybrid population. The feather color of individuals in each family should be consistent with that of the maternal line. The feathers of the Sanhuang chicken family are pure yellow, and the feathers of the Ma chicken family are brownish-yellow. Each individual should weigh more than 3.0 kg at 300 days of age.

6. The method for breeding Changfeng native chickens according to claim 1, characterized in that, During the backcrossing process in step c), the selected maternal individuals should lay no less than 160 eggs at 300 days of age, with light brown eggshells and a shell thickness of 0.35 mm to 0.40 mm.

7. The method for breeding Changfeng native chickens according to claim 1, characterized in that, In the multi-generational selection process in step d), the individuals selected in each generation shall have a weight of not less than 3.2 kg at 300 days of age, and the weight of the pectoral muscles shall account for not less than 22% of the body weight.

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