A method for culturing low-quality grey sea horse seedlings by using hydrodynamic principle and hierarchical culture

Abstract

The present application relates to a kind of low quality seedling of grey pipefish cultivation method using hydrodynamic principle and hierarchical culture.The method comprises the following steps:A, low quality grey pipefish is placed in dark barrel;B, air stone is placed in the center of the bottom of the barrel in step A, and the air volume is adjusted;C, after 12-14 days, the water level is increased to 45-50 cm, and after 20 days, the water level is increased to 60-65 cm, after adjusting the water level, the air volume is also adjusted;D, 8-15 days, the weak seedlings in the barrel are fished out and placed in a new barrel, and the weak seedlings are continuously fished out and placed in a new barrel during cultivation, and then cultivated according to the above steps.The method can increase the survival rate of 20 days in clear water from less than 10% to more than 80%, and improve the efficiency of sea horse cultivation.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of hippocampus seedling cultivation, and particularly relates to a method for culturing low-quality Hippocampus erectus seedlings by using hydrodynamics principle and hierarchical culture. BACKGROUND

[0002] Hippocampus is a traditional precious Chinese medicine. According to statistics, more than 300 tons of dry products are used for medicine in China every year. As China's natural resources have been exhausted, most of the market demand for Hippocampus is currently met by imports, and the price is increasing year by year, with an average price of more than 7,000 yuan per kilogram. According to the annual import of 300 tons, the value exceeds 2.1 billion yuan. Due to the serious destruction of Hippocampus natural resources, many countries in the world have carried out artificial cultivation research to restore resources. In the past five years, Hippocampus cultivation technology has developed rapidly in China, mainly with Hippocampus erectus and H. abdominalis as the leading varieties, but there are still many problems in large-scale production technology. The proportion of low-quality seedlings due to degeneration of germplasm is increasing, and the low survival rate of low-quality seedling cultivation is one of the main problems that need to be solved at present.

[0003] Hippocampus can reproduce multiple times a year, and in nature, the breeding season is generally in spring and autumn, mainly in spring. Under artificial conditions, it can reproduce throughout the year, but the quality of the seedlings decreases after multiple consecutive breeding in summer. The main performance is thin or with bubbles. At present, Hippocampus cultivation generally uses clear water. In clear water, low-quality newborn seedlings float on the water surface, affecting feeding and becoming more thin or having bubbles; if the newborn seedlings have no obvious bubbles, they will float on the water surface, and the bubbles will be more obvious, and generally all die within 7 days. The survival rate of low-quality seedlings is generally less than 10% when they are cultivated to 20 days. A large number of low-quality seedlings will significantly affect the efficiency of Hippocampus cultivation. Therefore, how to improve the survival rate of low-quality Hippocampus erectus seedlings is one of the important problems that need to be solved in Hippocampus cultivation at present.

[0004] High-quality Hippocampus erectus newborn seedlings have strong adaptability, and live in water immediately after hatching, even if some are on the surface, but will not float on the water surface. Generally, 1-3 days after hatching, they will completely enter the water and will not appear bubbles. In view of this behavioral characteristic, if low-quality newborn seedlings can be induced into water, it will be helpful for the seedlings to feed, thereby improving their survival rate. Chinese patent CN201910485564.1 discloses algae water cultivation to achieve this goal. However, the algae water cultivation technology requires high technical level, and the algae phase is not easy to control. Therefore, it is of great significance to establish a simpler technology for Hippocampus erectus low-quality seedling cultivation. SUMMARY

[0005] The technical problem solved by the present application is to provide a method for culturing low-quality Hippocampus kuda juveniles by using the principle of water dynamics and hierarchical culture, so as to overcome the low survival rate of low-quality Hippocampus kuda juveniles in the prior art.

[0006] In Hippocampus kuda culture, the common practice in the juvenile stage is trace aeration, and some scholars even attribute the bubble disease to large aeration amount. However, the inventors found that in a suitable size round barrel, the water flow generated by large aeration can bring the juveniles into the water, and the low-quality juveniles, even the juveniles with bubbles, are rarely floating on the water surface, and will enter the water body, which is beneficial to feeding, and will not contact air to cause bubbles in the swim bladder or further increase of the bubbles in the bubble juveniles, and the bubbles in the bubble juveniles basically disappear after 20 days.

[0007] The present application provides a method for culturing low-quality Hippocampus kuda juveniles by using the principle of water dynamics and hierarchical culture, comprising:

[0008] A. Put low-quality Hippocampus kuda into a dark barrel, and the light intensity is 200-700 lx, wherein the diameter of the dark barrel is 1.0-1.2 meters, and the water level is 35-40 cm when the juveniles are put in;

[0009] B. Place gas stone in the dark barrel in step A, and the gas stone is placed at the center of the barrel bottom. The traditional trace aeration cannot be adopted, and the water circle diameter formed by aeration on the water surface reaches 24-26 cm, so as to ensure that no juveniles float on the water surface, and at the same time, it is appropriate to ensure that the Hippocampus kuda maintains normal swimming state in the water body;

[0010] C. After 12-14 days, the water level is increased to 45-50 cm. After adjusting the water level, the aeration amount needs to be slightly increased based on step B, and the water circle diameter formed by aeration on the water surface reaches 25-27 cm, so as to ensure that no juveniles float on the water surface, and at the same time, it is appropriate to ensure that the Hippocampus kuda maintains normal swimming state in the water body. After 20 days, when the body height of the Hippocampus kuda reaches 2.5 cm or more, the water level is increased to 60-65 cm, and the aeration amount does not need to be adjusted;

[0011] D. Start to take out the weak juveniles in the barrel and put them into a new barrel after 8-15 days. The weak juveniles are continuously taken out and put into a new barrel during the cultivation process, and then the cultivation is carried out according to steps A-C.

[0012] Preferably, the low-quality Hippocampus kuda in step (A) is the late spawning of parent Hippocampus kuda, bubble juveniles, or juveniles with a trunk width to trunk height ratio less than 0.19.

[0013] Preferably, the dark barrel in step (A) is blue or black.

[0014] Preferably, the diameter of the dark barrel is 1.0-1.2 meters, and the depth is 75-80 cm.

[0015] Preferably, the amount of seedlings in each barrel in step (A) is 200-300.

[0016] Preferably, one air stone is placed in the center of each dark barrel in step (B).

[0017] Preferably, the low-quality sea horses are controlled at a water temperature of 24-28℃ during cultivation, and EM bacteria and lactic acid bacteria are added to the cultivation water every 3 days. During cultivation, attention is paid to sucking up dead feed and feces, and no water change is needed within 20 days, and water can be supplemented after sucking up the dirt.

[0018] Preferably, the low-quality gray sea horses are fed with copepods during cultivation, with a feeding density of 1-2 / ml, and fed twice a day at 08:00 and 15:00 respectively.

[0019] Preferably, the thin seedlings are placed in new barrels at 150-200 seedlings per barrel.

[0020] Preferably, the barrels are not changed as much as possible during cultivation to avoid death caused by barrel stress, until the sea horses reach the commercial size (more than 10 cm).

[0021] Advantages

[0022] The present application is in a suitable size (diameter 1.0-1.2 meters) round barrel, the water depth is controlled at 35-40 cm, a single air stone is placed in the center of the barrel, and the flow formed by controlling the amount of air brings the low-quality gray sea horses into the water, reduces the incidence of bubble disease, and ensures that the sea horses can feed normally. This method can increase the survival rate of 20-day cultivation in clean water from less than 10% to more than 80%, and improves the efficiency of sea horse cultivation. If the water depth is more than 40 cm, or the barrel diameter is more than 1.2 meters, the amount of air needs to be increased, so the disturbance to the water body is too large, although the sea horses can be brought into the water body, but it is difficult for them to maintain normal swimming state, and they cannot feed normally, and it is difficult to achieve satisfactory results. DETAILED DESCRIPTION

[0023] The present application will be further described below in conjunction with specific examples. It should be understood that these examples are only used to illustrate the present application and not used to limit the scope of the present application. In addition, it should be understood that after reading the content taught by the present application, those skilled in the art can make various modifications or changes to the present application, and these equivalent forms also fall within the scope of the claims attached hereto.

[0024] Example 1

[0025] I. Cultivation system

[0026] The grey sea horse larvae breeding system is composed of a breeding tank, a water inlet and outlet system, and an air charging system. The breeding tank is made of glass fiber reinforced plastic, and the inner wall is black. The diameter of the tank is 1.0 m, 1.2 m, or 1.4 m, and the depth of the tank is 75 cm. The water depth for placing the larvae is 35 cm, 45 cm, or 55 cm.

[0027] II. Breeding environment

[0028] The water temperature for breeding the new-born larvae of the grey sea horse is 25-27℃, the salinity of the water for breeding is 30‰, the light time is 13 hours, the sunlight intensity is 200-700 lux, the sunlight intensity in the morning and evening is not less than 200 lux, and the sunlight intensity after sunrise is 400-700 lux (the light intensity is maintained for about 8 hours).

[0029] III. Feeding of bait

[0030] The larvae are fed with copepods, and the feeding density is 1-2 per ml. The larvae are fed twice a day at 08:00 and 15:00.

[0031] IV. Placing of larvae and breeding management

[0032] 200 larvae are placed in each tank. A gas stone is placed in the center of the bottom of each tank. The air volume is adjusted to just bring all the larvae into the water, and the sea horses are kept in a normal swimming state. The diameter of the water circle formed by the air charging on the water surface is 24-26 cm. EM bacteria and lactic acid bacteria are added every 3 days. The dead bait and feces are sucked out in time during the breeding period, and the water is not changed. After the suction of the feces, the water is supplemented. After 12 days, the water level of the tank with a water level of 35 cm or 45 cm is increased to 50 cm. After the adjustment of the water level, the air volume is also increased. The diameter of the water circle formed by the air charging on the water surface is 25-27 cm. All the larvae are brought into the water, and the sea horses are kept in a normal swimming state. When the body height of the sea horses is more than 2.5 cm, the water level is increased to 60-65 cm, and the air volume is not adjusted.

[0033] For the tanks with a diameter of 1.0 m and 1.2 m, when the water level is 35 cm, the appropriate water flow can be generated by controlling the air volume to bring all the larvae into the water, and a slow flow area is formed, and the larvae are distributed in the slow flow area. When the water level is higher than 45 cm, it is difficult to control the air volume, and a large air volume is needed to form a water flow to bring the larvae into the water. At the same time, the water is disturbed greatly, and a comfortable slow flow area cannot be formed. The larvae are easily rolled with the water flow, and the feeding is affected. The specific results are shown in Table 1.

[0034] Diameter 1.4-meter barrel: water level 35 cm is the best, but compared with diameter 1.0 and 1.2-meter barrels, it needs more air volume, but about 1% of the seedlings still cannot enter the water. In comparison, under the condition of water level 55 cm, it is difficult to control the air volume, and a large amount of air flow is needed to bring the seedlings into the water. Under the premise of ensuring normal swimming of the seahorses, about 3-5% of the seahorse seedlings cannot enter the water, especially the bubble seedlings. The specific results are shown in Table 1, and the calculation of the survival rate in Table 1 excludes weak seedlings.

[0035] In summary, the diameter 1.0-1.2-meter barrel with water level 35 cm when releasing the seedlings is the best.

[0036] During the cultivation process, weak seedlings are removed after 8 days, and seedlings with similar specifications are cultivated in another barrel. Within 20 days, about 10% of the weak seedlings in each barrel are removed. If these weak seedlings are not removed in time, they will all die slowly. After removal, they are cultivated according to the above method (selecting a diameter 1.0-meter barrel and releasing the seedlings with water level 35 cm), and the survival rate can reach 50% after 60 days.

[0037] Using this method, the survival rate of low-quality seedlings after 20 days can reach more than 80%.

[0038] Table 1 Average survival rate of low-quality seedlings in different diameter barrels and different water levels after 20 days (%)

[0039]

[0040] The above has specifically described the embodiments of the present application, but the present application is not limited to the described embodiments, and those skilled in the art can make various equivalent modifications or replacements without deviating from the spirit of the present application. These equivalent modifications or replacements are all included in the scope defined by the claims of the present application.

Claims

1. A method for culturing low-quality Hippocampus kelloggi by using water dynamics principle and hierarchical culture, comprising: A. Placing low-quality Hippocampus kelloggi in a dark barrel, with light intensity of 200-700 lx, wherein the diameter of the dark barrel is 1.0-1.2 meters, and the water level is 35-40 cm when placing the larvae; B. Placing a gas stone in the dark barrel in step A, which is placed at the center of the barrel bottom, and the diameter of the water circle formed by the gas filling on the water surface reaches 24-26 cm; C. After 12-14 days, the water level is increased to 45-50 cm, and after adjusting the water level, the gas filling amount needs to be slightly increased based on step B, and the diameter of the water circle formed by the gas filling on the water surface reaches 25-27 cm; after 20 days, when the body height of the Hippocampus kelloggi reaches more than 2.5 cm, the water level is increased to 60-65 cm, and the gas filling amount does not need to be adjusted; D. Start to take out the weak larvae from the barrel and place them in a new barrel after 8-15 days, and continuously take out the weak larvae and place them in a new barrel during the cultivation process, and then cultivate according to steps A-C. During the cultivation of the low-quality Hippocampus kelloggi, the water temperature is controlled at 24-28℃, EM bacteria and lactic acid bacteria are added to the cultivation water every 3 days; the larvae are fed with copepods, with a feeding density of 1-2 per ml, and fed twice a day; the barrel is not changed during the cultivation process until the body length of the Hippocampus kelloggi reaches more than 10 cm.

2. The method of claim 1, wherein, The low-quality Hippocampus kelloggi in step (A) is the late spawn of parent Hippocampus kelloggi, with bubble larvae, or larvae with a trunk width to trunk height ratio less than 0.

19.

3. The method of claim 1, wherein, The dark barrel in step (A) is blue or black; the diameter of the dark barrel is 1.0-1.2 meters, and the depth is 75-80 cm.

4. The method of claim 1, wherein, The number of larvae placed in each barrel in step (A) is 200-300.

5. The method of claim 1, wherein, The low-quality Hippocampus kelloggi is fed twice a day during the cultivation, at 08:00 and 15:00 respectively.

6. The method of claim 1, wherein, The number of weak larvae placed in the new barrel is 150-200 per barrel.

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