A method for rapid artificial hatching of saddle grouper eggs

Abstract

The application provides a rapid artificial hatching method for saddleband grouper eggs, which comprises the following steps: placing fertilized fish eggs in a container provided with debonding components, placing a spray pipe provided with a spray head in the container, adjusting the flow size to pretreat the fertilized fish eggs, obtaining pretreated fertilized fish eggs, and then placing the pretreated fertilized fish eggs in a hatching pool to hatch the fertilized eggs. The spray pipe provided with the spray head is placed in the container provided with the debonding components, the debonding agent is prepared by combining the debonding components and the adsorption carrier, the debonding agent is loaded into a mesh cloth bag and fixed in the container, the flow size of the spray head is adjusted, the fertilized eggs are pushed to the mesh cloth bags provided with the debonding agent around the container and at the bottom of the container, the fertilized eggs are in contact with the debonding components for a long time, the environment for embryo development is changed, the probability of embryo breaking the egg membranes is improved, and the hatching time is shortened.

Description

Technical Field

[0001] The invention relates to the technical field of fish egg hatching, in particular to an artificial rapid hatching method for saddle grouper eggs. Background Art

[0002] The saddleback grouper (Epinephelus lanceolatus) is a species of grouper, commonly known as dragon grouper and dragon gall grouper. It is a high-end fish and a highly consumed commercial species among groupers. Its rapid growth, strong disease resistance, adaptability, and ease of farming have led to its growing scale. Large-scale farming typically involves hatching large numbers of fertilized eggs produced through artificial induced fertilization. Fertilization is a critical step, and hatching is also a crucial process that cannot be overlooked. When hatching large numbers of fertilized eggs, they tend to aggregate and become squeezed, leading to hypoxia and embryonic malformations. This also increases the risk of bacterial infection, further reducing hatchability and potentially increasing the rate of malformations. Stable hatching plays a crucial role in the healthy growth and survival of subsequent fry. Rapid hatching of fertilized eggs not only improves industry efficiency but also plays a crucial role in the maintenance and development of the aquaculture industry, effectively improving the efficiency and economic benefits of saddleback grouper farming. Summary of the Invention

[0003] In view of this, the object of the present invention is to provide a method for artificial rapid hatching of saddle grouper eggs, so as to promote rapid development of the eggs and shorten the hatching time.

[0004] The technical solution of the present invention is achieved as follows:

[0005] A method for rapid artificial hatching of saddle grouper eggs comprises the following steps:

[0006] S1: placing fertilized fish eggs in a container provided with a debonding component, and pre-treating the fertilized fish eggs by placing a nozzle equipped with a spray head in the container and adjusting the flow rate to 80-120 L / min to obtain pre-treated fertilized fish eggs; preparing a debonding agent by combining the debonding component with an adsorption carrier, and loading the debonding agent into a mesh bag, and placing the mesh bag in the container to obtain the container provided with the debonding component;

[0007] S2: placing the fertilized fish eggs in a hatching tank for hatching.

[0008] The nozzle in the container is equipped with a spray head, which sprays water mist in the container through the nozzle, causing the water flow in the container to form a rolling phenomenon from bottom to top. The flow rate of the nozzle is controlled to push the fertilized eggs to the mesh bags filled with debonding agent set around and at the bottom of the container, so that they are in contact with the debonding components for a long time. At the same time, the nozzle is moved in a circle to cause the water body to generate a slight vortex of water potential and fluctuation, thereby dispersing each fertilized egg and making the fertilized egg fully contact with the debonding components. Under the action of the water pressure of the nozzle, the particles in the mesh bag are also flowing, which helps to evenly distribute the debonding agent in the mesh bag and avoid excessive friction between the mesh bag and the fertilized eggs.

[0009] A further solution is that the preparation method of the detackifying agent comprises: drying and crushing diatomaceous earth and vermiculite, adding cyclodextrin solution and talc powder, stirring, ultrasonicating, filtering, and collecting the precipitate to obtain the detackifying agent.

[0010] A further solution is that the mass volume ratio of the diatomaceous earth, vermiculite, cyclodextrin solution and talc is: 1-2g: 1-2g: 3-4L: 0.5-0.8g, and the mass concentration of the cyclodextrin solution is 15-25%.

[0011] A further solution is that the amount of the detackifying agent added is 50 to 350 g per kilogram of water in the container.

[0012] A further solution is that the adjustment flow rate is 80-100 L / min.

[0013] A further solution is that the mesh bag is placed on at least one surface of the container.

[0014] A further solution is that the movement rate of the nozzle in the container is 20 to 60 r / min, and the movement time is 10 to 30 minutes.

[0015] A further solution is that the movement speed of the nozzle in the container is 20 to 50 r / min.

[0016] A further solution is that the nozzle moves in a circular manner.

[0017] A further solution is that the fertilized fish eggs are obtained by using hormones to induce spawning of parent fish to release eggs and sperm, which are then mixed on site for fertilization, and the fertilized eggs are grouper fertilized eggs.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] The present invention places a nozzle with a spray head into a container provided with a debonding component, combines the debonding component with an adsorption carrier to make a debonding agent, puts the debonding agent into a mesh bag and fixes it in the container, adjusts the flow rate of the spray head, and pushes the fertilized eggs to the mesh bags provided with the debonding agent around and at the bottom of the container, so that the fertilized eggs are in contact with the debonding component for a long time, and at the same time changes the embryo development environment, thereby increasing the probability of the embryo breaking the egg membrane and shortening the incubation time.

[0020] In addition, the nozzle with the spray head is moved in a circle to generate a slight vortex of water potential and fluctuation in the water body, which affects the hatching and development mechanism of the embryo and promotes the rapid development of fish eggs. DETAILED DESCRIPTION

[0021] In order to better understand the technical content of the present invention, specific examples are provided below to further illustrate the present invention.

[0022] Unless otherwise specified, the experimental methods used in the examples of the present invention are all conventional methods.

[0023] Unless otherwise specified, the materials, reagents, etc. used in the examples of the present invention can be obtained from commercial sources.

[0024] Example 1

[0025] 100 g of diatomaceous earth and 100 g of vermiculite were dried and crushed, and 3 L of 20% cyclodextrin solution and 50 g of talc were added. After stirring and mixing, ultrasonic vibration was applied at 360 W for 1 hour, and the precipitate was filtered to obtain a detackifying agent.

[0026] Example 2

[0027] The fish eggs selected in this embodiment are induced-spawning fish eggs of saddle-banded grouper. The spawning is induced by artificial hormone injections to the parent fish, and the eggs and sperm are collected and discharged for mixing to complete fertilization. The fertilized eggs obtained by on-site fertilization are uniformly collected in an egg collection box, and then transferred to a container with debonding components on all sides and at the bottom. The container is provided with an outlet to form circulating water. The container is filled with water, and a debonding agent (Example 1) is prepared by mixing an adsorption carrier with the debonding component and is loaded into a soft mesh bag. The loading amount is 150g of debonding agent per kilogram of water. The mesh bag is fixed to the four sides and bottom of the container to obtain a container provided with a debonding component, and then a nozzle is placed below the liquid level inside the container from the outside. The nozzle is equipped with a spray head, and water mist is sprayed in the container through the nozzle, so that the water flow in the container forms a rolling phenomenon from bottom to top, pushing the fertilized eggs to the four sides and bottom of the container, and The debonding components are in contact for a long time, and the nozzle is moved in a circle to generate a slight vortex of water potential and fluctuation in the water body, which disperses the fertilized eggs and makes them fully contact with the debonding components. The nozzle's circle speed is controlled at 20-60r / min (when the nozzle circles, it is at least 10cm away from the surroundings and the bottom). The processing time is 20min. Under the action of the nozzle water pressure, the particles in the mesh bag are also flowing, which helps to evenly distribute the debonding agent in the mesh bag and avoid excessive friction with the fertilized eggs. The eggs are taken out and placed in the hatching tank to observe the hatching of the eggs. After all the eggs are hatched, the final total hatching time, hatching rate and fry deformity rate are recorded. The statistics are shown in the following table.

[0028] Table 1 Hatching of embryos at different winding rates

[0029] <![CDATA[速率 / r·min -1 ]]> Incubation time / h Hatching rate / % Deformity rate / % 20 20 90.3 6.7 40 17 92.5 7.6 60 15 70.3 13.8 —— 24 88.6 5.3

[0030] Note: “——” means no movement, only water spray

[0031] The results in Table 1 above show that as the nozzle's circling speed gradually increases, the embryo's incubation time gradually shortens, the hatching rate first increases and then rapidly decreases, and the deformity rate gradually increases. This indicates that the nozzle helps promote the development of fish eggs at an appropriate movement speed. On the one hand, the increase in speed improves the full contact between the fish eggs and the debonding agent. On the other hand, the resulting water potential fluctuations affect the embryo's hatching and development mechanism, resulting in premature hatching and shortening the incubation time.

[0032] Example 3

[0033] The fish eggs used in this embodiment are the induced spawning fish eggs of Epinephelus saddleback. The spawning is induced by artificial hormone injection of parent fish, and the eggs and sperm are collected and mixed to complete fertilization. The fertilized eggs obtained by on-site fertilization are uniformly collected into the egg collection box, and then transferred to the container that all around and bottom are all provided with debonding component, container is provided with discharge outlet, can form circulating water, fill with water in the container, make debonding agent (embodiment 1) by adsorption carrier and debonding component mixing and pack into soft mesh bag, loading capacity is that every kilogram of water adopts 150g debonding agent, mesh bag is fixed to all around and bottom of container, obtain being provided with the container of debonding component, and then spray pipe is placed below the liquid level place of this container inside, this spray pipe is equipped with spray head, and controlling flow size is 80~120L / min, and spray pipe moves in circle with 40r / min speed simultaneously, processes 20min, and ovum is taken out and is placed incubator, observes the hatching situation of ovum, after ovum all hatches, record final total incubation time, hatchability and the deformity rate of larva, statistics are as follows table.

[0034] Table 2 Hatching of embryos under different debonding agent loadings

[0035] <![CDATA[流量 / L·min -1 ]]> Incubation time / h Hatching rate / % 80 19 91.7 100 16 89.6 120 15 83.2

[0036] The results in Table 2 above show that as the spray flow rate gradually increases, the embryo incubation time gradually shortens, while the hatching rate gradually decreases. Excessive flow rate can easily cause the egg membrane to rupture or interfere with the embryonic development mechanism, causing some fish eggs to die. Under the impact energy, the developing embryo can sensitively perceive changes in the external environment. When the external stimulus signal is amplified, the embryo's swing frequency increases, the probability of rupturing the egg membrane increases, and the hatching time is reduced.

[0037] Example 4

[0038] The fertilized eggs obtained by on-site fertilization in Example 2 were uniformly collected in an egg collection box and then transferred to the container of Example 2. The nozzle of Example 2 was then placed below the liquid level inside the container, and water mist was sprayed in the container through the nozzle. The nozzle was moved in a circle at a rate of 40 r / min for 20 min. The eggs were taken out and placed in an incubation tank. The hatching of the eggs was observed. After all the eggs were hatched, the final total incubation time, hatching rate and deformity rate of the fry were recorded, and the statistics were as shown in the following table.

[0039] Table 3 Hatching of embryos under different debonding agent loadings

[0040] Filling amount / g Incubation time / h Hatching rate / % 50 19 90.5 250 18 91.5 350 20 89.0

[0041] Note: “Filling amount” means the amount of debonding agent added per kilogram of water in the container

[0042] The results in Table 3 above show that the amount of debonding agent added has little effect on the hatching time and hatching rate of fish eggs, but adding too much debonding agent will affect the final hatching effect of fish eggs.

[0043] Comparative Example 1

[0044] The fertilized eggs obtained by on-site fertilization in Example 2 were uniformly collected in an egg collection box, and a detackifying agent (Example 1) with a mass concentration of 15 wt% was added to the egg collection box. After stirring for 20 minutes, the eggs were taken out and placed in an incubation tank. The incubation time of the eggs was 27 hours, and the hatchability was 87.2%.

[0045] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for rapid artificial hatching of saddle grouper eggs, characterized in that: The steps include: S1: placing fertilized fish eggs in a container provided with a debonding component, and pre-treating the fertilized fish eggs by placing a nozzle equipped with a spray head in the container and adjusting the flow rate to 60-120 L / min to obtain pre-treated fertilized fish eggs; preparing a debonding agent by combining the debonding component and an adsorption carrier, and loading the debonding agent into a mesh bag, and placing the mesh bag in the container to obtain the container provided with the debonding component; The movement rate of the nozzle in the container is 20-50 r / min, and the movement time is 10-30 min; The preparation method of the detackifying agent comprises: drying and crushing diatomaceous earth and vermiculite, adding cyclodextrin solution and talc powder, stirring, ultrasonicating, filtering, and collecting precipitates to obtain the detackifying agent; S2: placing the fertilized fish eggs in a hatching tank for hatching; The mass volume ratio of the diatomaceous earth, vermiculite, cyclodextrin solution and talc is: 1-2 g: 1-2 g: 3-4 L: 0.5-0.8 g, and the mass concentration of the cyclodextrin solution is 15-25%; The amount of the detackifying agent added is 50 to 350 g per kilogram of water in the container; The mesh bag is placed on at least one surface of the container; The nozzle moves in a circular pattern.

2. The artificial rapid hatching method for Epinephelus saddleback eggs according to claim 1, wherein: The adjustment flow rate is 80~100 L / min.

3. The artificial rapid hatching method for Epinephelus saddleback eggs according to claim 1, wherein: The fertilized fish eggs are obtained by using hormones to induce spawning of parent fish to release eggs and sperm, and then mixing them on site to complete fertilization. The fertilized fish eggs are fertilized grouper eggs.