A method for measuring oyster gonad index

Abstract

The present invention provides a method for determining the gonadal index of oysters, and relates to the field of aquaculture technology. The method for determining the gonadal index of oysters comprises the following steps: S1, dissection: separating the left and right shells of the oysters and taking out the entire soft tissue of the oysters; S2, freezing: after the entire soft tissue of the oysters is dried of surface moisture, it is frozen at -24 ° C for 1-2 hours to set; S3, peeling: peeling off the gonadal tissue wrapped on the digestive caeca, and placing it and the remaining soft tissue after peeling in a fixed container respectively; S4, drying: drying the gonadal tissue and the remaining soft tissue at low temperature for 1-2 hours respectively; S5, weighing: weighing the gonadal tissue and the remaining soft tissue after drying respectively to obtain the gonadal tissue weight W1 and the remaining soft tissue weight W2; S6, formula calculation. The present invention can accurately measure the gonadal index of oysters, solve the problem of low measurement accuracy of traditional methods, and thus more accurately judge and evaluate the fullness and maturity of oyster gonads.

Description

Technical Field

[0001] The invention relates to the technical field of aquaculture, and in particular to a method for determining an oyster gonad index. Background Art

[0002] Oysters are a major species of aquaculture shellfish in my country. They are nutritious, plump, and highly economically valuable. They are found along my country's southeastern coast and prefer to inhabit intertidal zones. According to incomplete statistics from the National Shellfish Industry Technology System, my country's annual oyster production exceeded 5 million tons in 2022, generating an output value of 100 billion yuan.

[0003] Currently, the primary source of oyster seed is artificial seed cultivation. Since the 1980s, my country has seen rapid progress in oyster genetic breeding, which has also fueled the booming oyster seed cultivation industry. A sufficient supply of oyster seed also ensures the growth of the oyster aquaculture industry. Therefore, oyster genetic breeding and artificial seed cultivation are crucial to the oyster industry.

[0004] The gonad index (GOI) is a crucial measurement indicator in both oyster genetic breeding and artificial seed rearing. Traditional methods for measuring the oyster GOI, or gonadal index, often use the ratio of gonad area to soft body area or the ratio of gonad cross-sectional thickness to the entire soft body cross-sectional diameter. Because the gonad is soft and irregular in shape, measurement is challenging and inaccurate, impacting the efficiency and accuracy of oyster genetic breeding and artificial seed rearing. Summary of the Invention

[0005] (1) Technical problems solved

[0006] In view of the shortcomings of the existing technology, the present invention provides a method for measuring the gonad index of oysters, which solves the problems of high difficulty and low accuracy in the traditional oyster gonad index measurement process.

[0007] (2) Technical solution

[0008] To achieve the above objectives, the present invention is implemented through the following technical solutions: A method for measuring the oyster gonad index comprises the following steps:

[0009] S1. Dissection: Separate the left and right shells of the oyster to be measured for gonadal index, cut the adductor muscle, and remove the entire soft tissue of the oyster;

[0010] S2. Freezing: After the surface moisture of the entire soft tissue of the dissected oyster is absorbed, it is placed in a plastic tray and frozen at -24°C for 1-2 hours to set;

[0011] S3. Stripping: Use scissors and forceps to peel off the gonadal tissue wrapped around the digestive caeca and place it in a fixed container separately from the remaining soft tissue after stripping;

[0012] S4, drying: the peeled gonad tissue and the remaining soft tissue after peeling are respectively dried at low temperature for 1-2 hours;

[0013] S5, weighing: weighing the dried gonadal tissue and the remaining soft tissue separately to obtain the gonadal tissue weight W1 and the remaining soft tissue weight W2;

[0014] S6. Calculate using the formula W1 / (W1+W2)*100%, which is the gonad index of the oyster being measured.

[0015] Preferably, in step S1, the adductor muscles are cut along the base of the adductor muscles of the left and right shells of the oyster using an oyster knife, so that the entire soft tissue of the oyster is completely separated from the left and right shells.

[0016] Preferably, in step S2, the surface moisture of the soft tissue is absorbed by wrapping the entire soft tissue of the oyster with absorbent paper.

[0017] Preferably, in step S2, the soft tissue is shaped to a state that is stiff but not completely stiff, which can be determined by easily peeling off the gonadal tissue with scissors, tweezers or a scalpel without dissolving it.

[0018] Preferably, in step S4, the low-temperature drying operation is performed in a drying oven at 45-60°C.

[0019] One of the applications of the above-mentioned method for determining the oyster gonad index:

[0020] Application in oyster breeding: In oyster genetic breeding, the method is used to regularly measure the gonad index of oysters, which can be used to comprehensively evaluate the gonad fullness of their parents. In the early stage of gonad development, when the gonad index of parent oysters is greater than 25%, they can be used for breeding offspring.

[0021] The second application of the above-mentioned method for determining the oyster gonad index:

[0022] Application in artificial oyster breeding: In artificial oyster breeding, the method is used to regularly measure the gonad index of oysters in the middle and late stages of oyster gonad development, i.e., during gonad maturation, to comprehensively evaluate the maturity of the gonads, thereby determining the time and method for large-scale oyster spawning.

[0023] Preferably, the method for determining the egg collection time is: during the maturation of the oyster gonads, the gonad index of the oysters is measured every 3-15 days, and when the gonad index is above 38%, large-scale egg collection can be arranged.

[0024] Preferably, the method for determining the egg collection method is: during the maturation of the oyster gonads, the gonad index of the oysters is measured every 3-15 days. When the gonad index is in the range of 38%-50%, the egg collection method of manual dissection can be adopted; when the gonad index is above 50%, the egg collection method of natural ovulation can be adopted.

[0025] (3) Beneficial effects

[0026] The present invention provides a method for determining the gonadal index of oysters. It has the following beneficial effects:

[0027] 1. The present invention can accurately measure the oyster gonad index, solving the problem of low measurement accuracy of traditional methods, thereby more accurately judging and evaluating the fullness and maturity of the oyster gonads.

[0028] 2. The determination method provided by the present invention can be operated in batches and accurately evaluate the development of oyster gonads, which can provide a guarantee for future oyster genetic breeding and artificial seedling cultivation. DETAILED DESCRIPTION

[0029] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only 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 making creative efforts are within the scope of protection of the present invention.

[0030] Example 1:

[0031] The embodiment of the present invention provides a method for measuring the gonadal index of an oyster, comprising the following steps:

[0032] S1. Dissection: Use an oyster knife to separate the left and right shells of the oyster to be measured for gonadal index, cut the adductor muscle, and remove the entire soft tissue of the oyster;

[0033] Among them, cutting the adductor muscle is to use an oyster knife to cut along the base of the adductor muscle of the left and right shells of the oyster, so that the entire soft tissue of the oyster is completely separated from the left and right shells;

[0034] S2. Freezing: After the surface moisture of the entire soft tissue of the dissected oyster is absorbed, it is placed in a plastic tray and frozen at -24°C for 1-2 hours to set;

[0035] The method of drying the surface moisture of the soft tissue is to wrap the entire soft tissue of the oyster with absorbent paper to dry the surface moisture of the entire soft tissue of the oyster;

[0036] Among them, the shape is fixed by freezing at -24℃ for 1-2 hours until it is stiff but not completely stiff. The judgment method is that the gonadal tissue can be easily peeled off with scissors, forceps or scalpel without dissolving;

[0037] S3. Stripping: Use scissors and forceps to peel off the gonadal tissue wrapped around the digestive caeca and place it in a fixed container separately from the remaining soft tissue after stripping;

[0038] S4, drying: the peeled gonad tissue and the remaining soft tissue after peeling are respectively dried at low temperature for 1-2 hours;

[0039] Among them, low-temperature drying is carried out in a drying oven at 45-60°C;

[0040] S5, weighing: weighing the dried gonadal tissue and the remaining soft tissue separately to obtain the gonadal tissue weight W1 and the remaining soft tissue weight W2;

[0041] S6. Calculate using the formula W1 / (W1+W2)*100%, which is the gonad index of the oyster being measured.

[0042] Example 2:

[0043] The present invention provides an application of the determination method in Example 1 in oyster breeding:

[0044] In oyster genetic breeding, the method is used to regularly measure the gonad index of oysters, which can be used to comprehensively evaluate the gonad fullness of their parents. In the early stage of gonad development, when the gonad index of the parent oyster is greater than 25%, it can be used to breed offspring.

[0045] Example 3:

[0046] The present invention provides an application of the determination method in Example 1 in artificial oyster seedling cultivation:

[0047] In the artificial breeding of oysters, the gonad index of oysters is regularly measured using the method in the middle and late stages of oyster gonad development, i.e., during gonad maturation. This can be used to comprehensively evaluate the maturity of the gonads, thereby determining the time and method for large-scale oyster spawning.

[0048] Specifically, the method for determining the egg collection time is: during the maturation of the oyster gonads, the oyster gonad index is measured every 3-15 days. When the gonad index is above 38%, large-scale egg collection can be arranged.

[0049] Specifically, the method for determining the egg collection method is: during the maturation of the oyster gonads, the oyster gonad index is measured every 3-15 days. When the gonad index is in the range of 38%-50%, the egg collection method of manual dissection can be adopted; when the gonad index is above 50%, the egg collection method of natural ovulation can be adopted.

[0050] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A method for determining the gonadal index of oysters, characterized in that: The steps include: S1. Dissection: Separate the left and right shells of the oyster to be measured for gonadal index, cut the adductor muscle, and remove the entire soft tissue of the oyster; S2. Freezing: After the surface moisture of the entire soft tissue of the dissected oyster is absorbed, it is placed in a plastic tray and frozen at -24°C for 1-2 hours to set; S3. Stripping: Use scissors and forceps to peel off the gonadal tissue wrapped around the digestive caeca and place it in a fixed container separately from the remaining soft tissue after stripping; S4, drying: the peeled gonad tissue and the remaining soft tissue after peeling are respectively dried at low temperature for 1-2 hours; S5, weighing: weighing the dried gonadal tissue and the remaining soft tissue separately to obtain the gonadal tissue weight W1 and the remaining soft tissue weight W2; S6, formula calculation, use the formula This is the gonad index of the oyster being tested; In step S2, the soft tissue is fixed to a state that is stiff but not completely stiff, as determined by the gonadal tissue being easily peeled off with scissors, forceps, or a scalpel without dissolving; In step S4, the low-temperature drying operation is performed in a drying oven at 45-60°C.

2. The method for determining the oyster gonad index according to claim 1, wherein: In step S1, the adductor muscles are cut along the base of the adductor muscles of the left and right shells of the oyster using an oyster knife, so that the entire soft tissue of the oyster is completely separated from the left and right shells.

3. The method for determining the oyster gonad index according to claim 1, wherein: In step S2, the surface moisture of the soft tissue is absorbed and the entire soft tissue of the oyster is wrapped with absorbent paper.

4. The method for determining the oyster gonad index according to any one of claims 1 to 3 is used in oyster genetic breeding and artificial seedling cultivation.

5. The use according to claim 4, characterized in that: In oyster genetic breeding, the method is used to regularly measure the gonad index of oysters, which can be used to comprehensively evaluate the gonad fullness of their parents. In the early stage of gonad development, when the gonad index of the parent oyster is greater than 25%, it can be used to breed offspring.

6. The use according to claim 4, characterized in that: In the artificial breeding of oysters, the gonad index of oysters is regularly measured using the method in the middle and late stages of oyster gonad development, i.e., during the gonad maturation process. This can be used to comprehensively evaluate the maturity of the gonads, thereby determining the time and method for large-scale oyster spawning.

7. The use according to claim 6, characterized in that: The method for determining the egg collection time is as follows: during the maturation of the oyster gonad, the gonad index of the oyster is measured every 3-15 days, and when the gonad index is above 38%, large-scale egg collection can be arranged.

8. The use according to claim 6, characterized in that: The method for determining the egg collection method is as follows: during the maturation of the oyster gonad, the gonad index of the oyster is measured every 3-15 days. When the gonad index is in the range of 38%-50%, the egg collection method of manual dissection can be adopted; when the gonad index is above 50%, the egg collection method of natural ovulation can be adopted.

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