A breeder selection method for reducing the egg weight increment of laying hens before and after laying

Abstract

The present invention provides a method for selecting breeders that reduces the increment of egg weight before and after laying, and relates to the technical field of laying hen selection. The breeder selection method mainly includes strain breeding, egg number and egg weight statistics, and uses three indicators, namely, the number of eggs laid at 56 weeks of age, the egg weight at 40 weeks of age, and the increment of egg weight before and after laying, to establish a comprehensive selection index, set up a calculation formula, and accurately screen strains and individuals to obtain new varieties or strains of laying hens with high egg production, appropriate egg weight, and small difference in egg weight before and after laying. The present invention overcomes the shortcomings of the prior art, establishes a comprehensive selection index for strains of laying hens, and conducts systematic and scientific seed selection, thereby reducing the increment of egg weight before and after laying, appropriately increasing egg production, maintaining average egg weight, and improving the economic benefits of laying hen breeding.

Description

Technical Field

[0001] The invention relates to the technical field of laying hen selection, and in particular to a breeding hen selection method for reducing the egg weight increment of laying hens before and after laying. Background Art

[0002] Eggs are an important food in people's daily life. my country's egg production accounts for about 35% of the world's total egg production. Egg chicken farming is an important part of my country's agriculture.

[0003] When raising laying hens, we must first select laying hen breeds with high egg production and good egg quality. With the development of the egg market, the sales end has more and more stringent requirements on egg size, especially when eggs are sold individually. While the weight of the eggs is required to reach a certain specification, the size of the eggs must also be relatively uniform. In other words, eggs with reasonable weight and uniform size are more popular, and have a high price and good economic benefits.

[0004] Laying hens usually start laying eggs at 140-150 days old. The first eggs are usually small. As the age of the chicken increases, the egg weight continues to increase. The egg weight is larger in the later stage of laying. That is, the egg weight increase of most chickens from the early stage of laying (soon after laying) to the late stage of laying (56 weeks) is between 5-45%. There are large individual differences, and the coefficient of variation is more than 35%. If eggs are sold individually or by brand, smaller eggs in the early stage and larger eggs in the later stage will not have good economic benefits. Therefore, chicken farmers hope that the laying hen breeds they raise should have the characteristics of not too small eggs in the early stage of laying, not too large eggs in the later stage of laying, high total egg production, and appropriate average egg weight.

[0005] In current laying hen breeding, egg number and egg weight are the primary selection targets. For egg weight selection, the current practice is to use egg weight at 40 or 43 weeks of age as the selection indicator, without systematically involving the selection of egg weight increments during the entire laying period. It is impossible to obtain varieties with small differences in egg weight before and after laying, which affects the actual economic benefits of laying hen production. Summary of the invention

[0006] In view of the shortcomings of the prior art, the present invention provides a method for selecting breeding hens that reduces the egg weight increment before and after laying hens, establishes a comprehensive selection index, and conducts systematic and scientific breeding of breeding hens, so as to reduce the egg weight increment before and after laying hens, appropriately increase egg production, maintain average egg weight, and improve the economic benefits of laying hen production.

[0007] To achieve the above objectives, the technical solution of the present invention is implemented through the following technical solutions:

[0008] A method for selecting breeder chickens for reducing the weight increment of eggs in the early and late stages of laying hens, the method comprising the following steps:

[0009] (1) After the selected strain is determined, pure breeding is carried out, the pedigree is registered, conventional feeding and management are carried out until the chickens are 18 weeks old, and they are transferred to the egg-laying house and raised in individual cages, and the number of eggs laid by each chicken is recorded;

[0010] (2) At 56 weeks of age, the number of eggs laid by each hen was counted and the mean number of eggs laid by the group was calculated;

[0011] (3) Determine the egg weight of each hen before, during, and after egg laying, and calculate the mean egg weight of the group of hens in the mid-egg laying period;

[0012] (4) Calculate the egg weight increment before and after egg laying, and calculate the mean egg weight increment before and after egg laying of the group of hens;

[0013] (5) Construction and calculation of comprehensive selection index: Using the above three indicators of egg production, mid-term egg weight, and egg weight increment, a comprehensive selection index calculation formula is established to calculate the comprehensive index value of each hen, as shown in the following formula:

[0014]

[0015] Where: I is the comprehensive selection index; EN is the number of eggs laid by hens at 56 weeks of age; W is the average number of eggs produced by the group at 56 weeks of age; 中 The egg weight of hens during mid-laying period; ΔW is the average egg weight of the group during the mid-laying period; 前后 Increase egg weight for hens before and after laying eggs; is the average value of the egg weight increment before and after egg laying in the group; P1, P2, and P3 represent the selection weights of egg laying number, mid-term egg weight, and egg weight increment before and after egg laying, respectively; P1+P2+P3=100, and the values ​​of the three are given specific values ​​according to the focus of the selection target;

[0016] (6) Breed selection and succession: Families and individuals are selected from high to low according to the comprehensive selection index, and then continued for pure breeding. After several generations of breeding, new breeds or strains of laying hens with high egg production, appropriate egg weight, and small difference in egg weight between the early and late stages are obtained.

[0017] Preferably, the egg weight of each hen in the early stage of egg laying in step (3) is calculated as follows: each hen is weighed starting from the sixth egg laid, and three non-double-yolked eggs are weighed continuously, and the weights are recorded as x1, x2, and x3 respectively, and the average value is calculated as the egg weight in the early stage of egg laying, recorded as W 前 :

[0018] W 前 =(x1+x2+x3) / 3.

[0019] Preferably, the egg weight of each hen in the middle of egg laying in step (3) is calculated as follows: when each hen is 40 weeks old, three non-double-yolked eggs are weighed continuously, and the weights are recorded as y1, y2, and y3 respectively, and the average value is calculated as the egg weight in the middle of egg laying, recorded as W 中 :

[0020] W 中 =(y1+y2+y3) / 3;

[0021] W of all hens 中 Calculate the arithmetic mean to obtain the average egg weight of the group in the middle of egg laying, recorded as

[0022] Preferably, the egg weight of each hen in the late egg-laying period in step (3) is calculated as follows: when each hen is 56 weeks old, three non-double-yolked eggs are weighed continuously, and the weights are recorded as z1, z2, and z3 respectively, and the average value is calculated as the egg weight in the late egg-laying period, recorded as W 后 :

[0023] W 后 =(z1+z2+z3) / 3.

[0024] Preferably, in step (4), the egg weight increment ΔW of each hen before and after laying eggs is calculated. 前后 =W 后 -W 前 , ΔW 前后 If it is a negative value, the hen will be eliminated, and the ΔW of the remaining hens 前后 Calculate the arithmetic mean to obtain the mean value of the egg weight increment before and after egg laying in the group, recorded as

[0025] Preferably, the selection method in step (6) is to select families according to the mean of the family index from high to low, and then select individuals from the selected families according to the index from high to low. The selection ratio of families and individuals within families is flexibly determined according to the actual size of the breeding population.

[0026] The present invention provides a method for selecting breeder hens for reducing the egg weight increment in the early and late stages of laying hens, which has the advantages over the prior art in that:

[0027] (1) The seed selection method of the present invention can reduce the proportion of small eggs in the early stage of laying and the proportion of large eggs in the late stage of laying, so that the egg weight increment in the early and late stages of laying decreases, thereby increasing the proportion of eggs with moderate egg weight, which is beneficial to egg sales and premium, and improves the economic benefits of laying hen production;

[0028] (2) The seed selection method of the present invention can effectively increase the total egg production of laying hens.

[0029] (3) The seed selection method of the present invention can enable laying hens to maintain an average egg weight within a reasonable range throughout the entire laying period, thereby improving the uniformity of egg weight. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention is clearly and completely described below in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] Example:

[0032] The breeding of laying hens is carried out with the following goals: reduce the increase in egg weight before and after laying, appropriately increase egg production, and maintain a stable average egg weight. The specific implementation steps are as follows:

[0033] 1. Determine the selected strain: Use the D5 laying hen strain, which is obtained by crossbreeding Guifei chickens and Hailan brown-shell laying hens, and then cross-crossing and fixing, and then selecting for two generations;

[0034] 2. Breeding: Pure breeding of the above-mentioned D5 laying hen strain, 80 families, pedigree hatching, 8,000 chicks were obtained, all female chicks were kept after sex identification, 8 healthy male chicks were selected from each family, wing numbers were attached, pedigrees were registered, conventional feeding and management were carried out, overweight, underweight and underdeveloped individuals were appropriately eliminated during adolescence, and they were transferred to laying houses at 18 weeks of age and raised in individual cages, with a total number of hens in individual cages of more than 3,000;

[0035] 3. From the day the eggs are laid, individual egg production records are kept until the age of 56 weeks. The number of eggs laid by each hen at 56 weeks of age is counted and recorded as EN. The arithmetic mean of the EN of all hens is calculated to obtain the mean number of eggs laid by the group at 56 weeks of age, which is recorded as

[0036] 4. Determination of egg weight in the early stage of egg laying: Each hen was weighed starting from the sixth egg it laid, and three non-double-yolk eggs were weighed continuously. The weights were recorded as x1, x2, and x3 respectively. The average value was calculated as the egg weight in the early stage of egg laying, recorded as W 前 , W 前 =(x1+x2+x3) / 3;

[0037] 5. Determination of egg weight in the middle of egg laying: When each hen is 40 weeks old, weigh three non-double-yolk eggs continuously, and record the weights as y1, y2, and y3 respectively. Calculate the average value as the egg weight in the middle of egg laying, recorded as W 中 , W 中 =(y1+y2+y3) / 3, W of all hens中 Calculate the arithmetic mean to obtain the average egg weight of the group in the middle of egg laying, recorded as

[0038] 6. Determination of egg weight in the late egg-laying period: When each hen is 56 weeks old, weigh three non-double-yolk eggs in succession. The weights are recorded as z1, z2, and z3 respectively. The average value is calculated as the egg weight in the late egg-laying period, recorded as W 后 , W 后 =(z1+z2+z3) / 3;

[0039] 7. Calculation of egg weight increment before and after egg laying: Calculate the egg weight increment ΔW before and after egg laying for each hen based on the egg weight measurement results before and after egg laying described in steps 4 and 6. 前后 =W 后 -W 前 , ΔW 前后 If it is a negative value, the hen will be eliminated and the ΔW of the remaining hens will be 前后 Calculate the arithmetic mean to obtain the mean value of the egg weight increment before and after egg laying in the group, recorded as

[0040] 8. Construction and calculation of comprehensive selection index: The calculation formula of comprehensive selection index is established by using the three indicators of egg production, mid-term egg weight and egg weight increment. According to the selection target of this example strain, P1, P2 and P3 are assigned 40, 20 and 40 respectively, and the formula is as follows:

[0041]

[0042] According to the formula, the comprehensive index of each hen is first calculated, and then the average index of each family is calculated by comparing the pedigree;

[0043] 9. Seed selection and succession: Select families according to the family mean from high to low, and the proportion of selected families is 50%. Then, from each selected family, select 60% of the individuals according to the index from high to low. The final proportion of hens selected is about 30%. 80 roosters are selected by sibling selection. After seed retention, 80 families are reorganized and the next generation of pure breeding is continued at 57-60 weeks of age;

[0044] 10. Determination of breeding effect: According to the above method, after two generations of breeding, the main indicators of this strain are as follows Table 1:

[0045] Table 1

[0046]

[0047]

[0048] As can be seen from Table 1 above, after two generations of breeding, the egg production of this breed increased by 1.95 eggs (an increase of 1.04%), the average egg weight remained basically the same, and the increase in egg weight between the early and late stages decreased by 3.21g (a decrease of 17.41%), that is, the goal of reducing the increase in egg weight between the early and late stages, increasing egg production, and maintaining the average egg weight was achieved.

[0049] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0050] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for selecting breeders to reduce the egg weight increment of laying hens in the early and late stages of egg laying, characterized in that: The method for selecting breeder chickens comprises the following steps: (1) After the selected strain is determined, pure breeding is carried out, the pedigree is registered, conventional feeding and management are carried out until the chickens are 18 weeks old, and they are transferred to the egg-laying house and raised in individual cages, and the number of eggs laid by each chicken is recorded; (2) At 56 weeks of age, the number of eggs laid by each hen was counted and the mean number of eggs laid by the group was calculated; (3) Determine the egg weight of each hen before, during, and after egg laying, and calculate the mean egg weight of the group of hens during the mid-egg laying period; (4) Calculate the egg weight increment before and after egg laying, and calculate the mean egg weight increment of the hens in the group before and after egg laying; (5) Construction and calculation of comprehensive selection index: Using the above three indicators of egg production, mid-term egg weight, and egg weight increment, a comprehensive selection index calculation formula is established to calculate the comprehensive index value of each hen, as shown in the following formula: Where: I is the comprehensive selection index; EN is the number of eggs laid by hens at 56 weeks of age; W is the average number of eggs produced by the group at 56 weeks of age; 中 The egg weight of hens during mid-laying period; ΔW is the average egg weight of the group during the mid-laying period; 前后 ΔW is the egg weight increment of hens before and after laying eggs; 前后 is the average value of the egg weight increment before and after egg laying in the group; P1, P2, and P3 represent the selection weights of egg laying number, mid-term egg weight, and egg weight increment before and after egg laying, respectively; P1+P2+P3=100, and the values ​​of the three are given specific values ​​according to the focus of the selection target; (6) Breed selection and succession: Families and individuals are selected from high to low according to the comprehensive selection index, and then continued for pure breeding. After several generations of breeding, new breeds or strains of laying hens with high egg production, appropriate egg weight, and small difference in egg weight between the early and late stages are obtained.

2. A method for selecting breeders for reducing the egg weight increment of laying hens in the early and late stages of egg laying according to claim 1, characterized in that: The calculation method of the egg weight of each hen in the early stage of egg laying in the step (3) is as follows: each hen is weighed starting from the sixth egg laid, and three non-double-yolked eggs are weighed continuously, and the weights are recorded as x1, x2, and x3 respectively, and the average value is calculated as the egg weight in the early stage of egg laying, recorded as W 前 : W 前 =(x1+x2+x3) / 3。 3. A method for selecting breeders for reducing the egg weight increment of laying hens in the early and late stages of egg laying according to claim 1, characterized in that: The egg weight of each hen in the middle of egg laying in step (3) is calculated as follows: when each hen is 40 weeks old, three non-double-yolked eggs are weighed continuously, and the weights are recorded as y1, y2, and y3 respectively, and the average value is calculated as the egg weight in the middle of egg laying, recorded as W 中 : <h2 style=";text-align:left;direction:ltr">W<h2 style=";text-align:left;direction:ltr"> 中 <h2 style=";text-align:left;direction:ltr"> (y1+y2+y3) / 3) W of all hens 中 Calculate the arithmetic mean to obtain the average egg weight of the group in the middle of egg laying, recorded as 4. A method for selecting breeders for reducing the egg weight increment of laying hens in the early and late stages of egg laying according to claim 1, characterized in that: The egg weight of each hen in the late egg-laying period in step (3) is calculated as follows: when each hen is 56 weeks old, three non-double-yolked eggs are weighed continuously, and the weights are recorded as z1, z2, and z3 respectively, and the average value is calculated as the egg weight in the late egg-laying period, recorded as W 后 : IN 后 =(z1+z2+z3) / 3。 5. A method for selecting breeders for reducing the egg weight increment of laying hens in the early and late stages of egg laying according to claim 1, characterized in that: In step (4), the egg weight increment ΔW of each hen before and after laying eggs is calculated. 前后 =W 后 -W 前 , ΔW 前后 If it is a negative value, the hen will be eliminated, and the ΔW of the remaining hens 前后 Calculate the arithmetic mean to obtain the mean value of the egg weight increment before and after egg laying in the group, recorded as 6. A method for selecting breeders for reducing the increase in egg weight in the early and late stages of laying hens according to claim 1, characterized in that: The selection method in step (6) is specifically to select families according to the average family index from high to low, and then select individuals from the selected families according to the index from high to low. The selection ratio of families and individuals within families is flexibly determined according to the actual size of the breeding population.

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