KR100588419B1 - Development of includuced spawning and seeding production techniques for the filefish - Google Patents

Abstract

The present invention relates to early spawning induction and seedling production method of the marlin.

Early spawning induction and seedling production method of the horsefish of the present invention, by raising the temperature of the breeding parenting to induce early spawning, and after spawning fertilized and hatched larvae to produce a suitable food organism and environment to produce seedlings It consists of.

According to the present invention, there is provided a method for inducing efficient early spawning of the marlin and a method for producing early feed organisms and seedlings suitable for the marlin.

Filefish, Early Spawning, Seedling Production, Rotifer

Description

Induction of early spawning and seedling production of horsefish {DEVELOPMENT OF INCLUDUCED SPAWNING AND SEEDING PRODUCTION TECHNIQUES FOR THE FILEFISH}             

Figure 1 is the overall process of early spawning induction and seedling production method of the horsefish

Figure 2 shows the results of breeding water temperature for artificial maturation and spawning induction of horsefish

Figure 3 shows the full-length growth results of horsefish larvae according to the breeding period

Figure 4 shows the weight growth results of horsefish larvae according to the breeding period

The present invention relates to spawning induction and seedling production method of the marlin.

The fillet is a fish belonging to Tetraodontida, Bluelistina and Aluteridae, and is a temperate fish distributed in the East, West and South Seas of Korea, the South Central Japan Sea, the East China Sea, and the Taiwan Sea. Inhabit them in groups where sand is less than 100 m deep.

Malfish is a fish species known to us. Although the larvae are a fish species with a high preference for food and have a high value for development as a useful fishery resource, it is now endangered due to the rapid decrease of coastal resources due to overfishing.

Recently, various studies have been conducted for the production of mass seedlings for endangered or reduced fish catches.

Since the spawning season is mid-May to the end of June, when the seedlings are produced during this period, the horsefish seedlings produced in the natural state due to the temperature of the coastal water temperature drop rapidly at the end of September. Since there is a problem that the productivity is lowered.

In addition, since the size of the hatchling freshly hatched eggs in eggs is difficult to mass production with the conventional seedling production method.

According to the Ministry of Oceans and Fisheries Research Report, Development of Mass Production Technology of Juvenile Seedlings (2001.12), adherent diatoms are the most suitable early feed organisms of juvenile larvae and show high growth rate and growth rate when fed to feed organisms.

However, there was a problem that the seedling is not produced in large quantities because the feeding of the diatoms to the feed organisms of the larvae was not fed.

In addition, the JoongAng Ilbo 'Development of Endangered Fish Farming Technology' (August 20, 2001) made phytoplankton and rotifers such as diatoms and green algae, such as diatoms and green algae, by making the seedling production tank 20 days before artificial eggs There is a method of producing seedlings by stably forming animal feed organisms such as copepoda.

In practice, however, omnivorous copepods feed on rotifers, the early food organisms of the marlin hatcheries, and are therefore not suitable for producing seedlings in large quantities.

On the other hand, Korean Patent No. 10-0291703 (method of fertilized egg production of perch), a method for producing a fertilized egg by treating the hormone analogs to the perch, and adjusting the water temperature and photoperiod.

Korean Patent Registration No. 0179336 (Method for Inducing Ovulation in Blessing) Injects gonadotropin, gonadotropin releasing hormone, or a mixture of gonadotropin releasing hormone and pimozide into female bokbok to induce ovulation of bokbok The method is public.

However, the above inventions are expensive because they use hormones to induce spawning, and they can be applied to the corresponding species. However, the present inventors did not show the effect of hormonal treatment on horsefish, which is a multi-scattering species.

In order to solve the above problems, an object of the present invention is to provide a method for inducing efficient early spawning of horsefish and a method for producing early food species and seedlings suitable for the fish.

The present invention relates to early spawning induction and seedling production method of the marlin.

Early spawning induction and seedling production method of the horsefish of the present invention, by raising the temperature of the breeding parenting to induce early spawning, and after spawning fertilized and hatched larvae to produce a suitable food organism and environment to produce seedlings It consists of.

The rotifer, which is used as an early food organism of the marlin larvae of the present invention, is a kind of small animal plankton known to have about 2,000 species in the world's water systems (mainly freshwater) (Nogrady et al., 1993).

Rotifers are very good organisms as the first food for larval fishes because of their small size, slow swimming speed, water-sustaining habits, dense cultivation capacity (10,000 individuals / ml), and high fertility.

According to the existing reports, it was found that the early food of the marlin larvae is adherent diatom or phytoplankton, but the experimental results of the present invention showed that the rotifer egg tended to be preferred over a long period from 5 days to 20 days of hatching.

The present invention induced early spawning at a time of 1 to 2 months earlier than the natural spawning season, and succeeded in early spawning of horsefish by simply adjusting the water temperature and photoperiod.

The early spawning induction and seedling production method of the horsefish of the present invention will be described in detail with reference to FIGS. 1 and 2 as follows.

1st step: secure fishfish

Three- to four-year-old larvae are secured, and reared at a temperature of 13 ° C in a flowing breeding tank.

Step 2: Induce Scattering

Management of Fish Fish Breeding The water temperature is gradually raised to 15 ° C. over 3 to 4 days (about 0.5 ° C./day) and maintained for 1 month.

The breeding water temperature is then raised to 17 ° C. over 3-4 days and then maintained at 17 ° C. for 4 weeks.

Then raise the breeding water temperature slowly to 18 ℃ over 2 ~ 3 days and start laying within 1 week.

Each stage photoperiod extends about 1 to 2 hours longer than the natural photoperiod.

Step 3: Gather hatching fish

The eggs are hatched after fertilization in the breeding tank for about 70 hours and then the hatched eggs are collected.

Or, if the eggs laid in the appropriate range of fertilization rate, the number of ranges that can be reared in the same tank, move the fish to another channel, hatch directly to enter the seedling production.

Step 4: seedling production

Prepare a land tank to raise hatched fish.

Inoculate chlorella at 1 million cells / ml into the water tank and then slowly maintain a concentration of 2-5 million cells / ml.

The water temperature is maintained at 19 ~ 21 ℃.

The hatched larvae are transferred to the prepared land tank at a rate of 6 to 10 individuals / l.

On day 2 of incubation the rotifers are inoculated at a concentration of 1-2 individuals / ml.

On the 5th day of hatching, hatchery eggs feed on rotifer eggs, so the rotifers are always maintained at a ratio of 2 to 3 individuals / ml. On the 10th day of hatching, the rotifers are increased to maintain the ratio of 5 to 8 individuals / ml. Mass production.

Hereinafter, the present invention will be described in detail with reference to Examples and Experimental Examples, but the present invention is not limited thereto.

Example 1 Early spawning, fertilization and hatching

Aquaculture broodstock or three- to four-year-old larvae caught on the west coast were secured and managed in a feeding breeding tank while maintaining the water temperature at 13 ° C.

The number of spawning larvae was 159 (75 females) in aquaculture and the mean weight was 452 g.

The wild horsefish larvae frequently secured hens for spawning in the waters near Anmyeon-do, Chungnam, and total 120 (71 females) with an average weight of 528 g.

The temperature was maintained at 13 ° C. in early February, and then gradually increased to 15 ° C. over 3 days from March 1, followed by 15 ° C. for 3 weeks.

The breeding water temperature was then raised to 17 ° C. over 3 days and then maintained at 17 ° C. for 4 weeks.

Later, the breeding water temperature was slowly raised to 18 ° C. over 2 days to start laying.

The photoperiod extended 1 to 2 hours from the natural light cycle, and after 2 hours, it turned off after the lighting time.

The spawned eggs started hatching about 70 hours after fertilization in the breeding tank, at which time the hatched eggs were collected.

In several experiments, the date of initial spawning was initiated in mid-April or early May, one to two months earlier than natural spawning, indicating that early spawning of horsefish was successful by simply adjusting the water temperature and photoperiod.

Example 2 Breeding and Production of Seedlings

A land tank to raise hatched fish was prepared.

Chlorella was inoculated at 1 million cells / ml in the land tank, and then maintained at a rate of 5 million cells / ml, and the water temperature was maintained at 19-21 ° C.

The hatched larvae were transferred to the prepared land tank at a rate of 10 individuals / l.

After 2 days of incubation, the rotifers were inoculated at a rate of 1 to 2 individuals / ml,

From the 5th day of hatching, additional rotifers were added and maintained at a ratio of 3 individuals / ml. On the 10th day of incubation, the amount of rotifers was increased to maintain the ratio of 8 individuals / ml to mass produce marlin seedlings.

Experimental Example 1 Investigation of Feeding Preference of Filefish

In the food preference survey for the breeding environment, as shown in Table 1, rotifer eggs were initially fed and rotifers were actively fed through the above contents analysis.

Seedling production in cultivated environment with chlorella and rotifers showed a survival rate of 70%. In the experimental group fed diatoms and chlorella, and the experimental group grown in open field, all of the larvae died.

In addition, as a result of measuring the full length and body weight up to 50 days after hatching in order to investigate the initial growth of the marlin larvae, as shown in Figure 3, the full length was 1.95 mm immediately after hatching 2.96 mm on the 10th day, 3.89 mm on the 20th day, On the 30th day, it grew to 12.9 mm, and on the 50th day to 35.1 mm, the weight showed rapid growth from the 30th day after hatching as shown in FIG.

<Table 1> Feeding Preference of Filefishes According to Breeding Environment

division Breeding period 3 days 5 days 10 days 20 days Survival rate (%)   Breeding environment  Zooplankton copepods nauplius                                          copepods nauplius copepods  11 Diatoms Our company 0 Chlorella Our company 0 Chlorella + rotifer  rotifer egg rotifer egg, small rotifer  rotifer  70 Outdoor Our company 0

According to the present invention, there is provided a method for inducing efficient early spawning of the marlin and a method for producing early feed organisms and seedlings suitable for the marlin.

Claims (4)

In the method of spawning induction and seedling production of fish, After collecting the larvae of the horsefish, while keeping the water temperature in the breeding tank to 13 ℃, After raising the water temperature in the breeding tank stepwise to 18 ℃ for 8 to 9 weeks and at the same time, photoperiod increased 1 to 2 hours from the natural light cycle to induce spawning of the fish Parent fishes are transferred to the land tank, and the remaining eggs are used directly for seedling production, or the eggs are hatched to collect eggs. After moving the collected fish to another land tank, While maintaining the water temperature in the land tank at 19 ~ 21 ℃, Breeding by feeding chlorella and rotifers as food Consisting of producing filefish seedlings, Early spawning induction and seedling production method of horsefish. The method of claim 1, In the process of inducing spawning of fish, When gradually raising the water temperature in the breeding tank, after slowly rising to 15 ℃ over 3 ~ 4 days at 13 ℃, maintained 15 ℃ for 3 weeks, and then slowly raised to 17 ℃ over 3 ~ 4 days Characterized by maintaining 17 ℃ for 4 weeks, then slowly rising to 18 ℃ over 2-3 days, Early spawning induction and seedling production method of horsefish. The method of claim 1, Inoculate chlorella into a terrestrial water tank to breed hatching larvae and inoculate at a concentration of 1 million cells / ml, and maintain the rate at 2 to 5 million cells / ml step by step. After 2 days of incubation, inoculate at 1 to 2 individuals / ml, and after 5 days of incubation, an additional rotifer is added and maintained at a rate of 2 to 3 individuals / ml, After 10 days of incubation, the rotifers are increased and maintained at a ratio of 5 to 8 individuals / ml. Early spawning induction and seedling production method of horsefish. The method of claim 1, Hatching larvae fed in the land tank is characterized in that the input density of 6 to 10 individuals / l, Early spawning induction and seedling production method of horsefish.

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