JP2011244795A - Method for producing on land of sand-submerged bivalves, such as littleneck clam - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for efficiently producing seedling of sand-submerged bivalves, such as little neck clams, under the decline of resources wherein seedling production relying on spontaneous generation or discharge is artificially produced on land which is less susceptible to nature.SOLUTION: Naturally or artificially-incubated larvae or rooted young shells of sand-submerged bivalves are housed in a simple rearing tank in which the earth is filled and rearing environments are created on land which is less susceptible to the marine environment such as ocean currents. Complex management is not required except for throwing in plant plankton regularly or irregularly, achieving the low cost and extensive production method.

Description

  The present invention relates to a method for producing submarine bivalves such as clams on land.

  Most of the submarine bivalves such as clams that are distributed as commodities are naturally produced, and it is difficult for non-fishers to enter production due to the establishment of fishing rights and fishing size regulations in each region. Most of the parts depended on the natural occurrence.

  In production areas, there are cases where artificial seedlings are produced and juveniles of about 2 mm are released into the habitat by ground-spreading methods. There are many places that have not appeared in the form of recovery.

  Also, in recent years, overfishing relative to the amount of resources and enormous damage caused by unprecedented predators have increased, making it difficult for young shellfish to settle and promoting resource reproduction.

  In addition, in the natural environment, there may be situations where it is difficult to provide a stable and safe supply to the market, such as shellfish poisoning or chemical contamination depending on the location.

  Artificial seedlings have been produced by many research institutes, but were raised in indoor aquariums and their food was also artificially cultivated, requiring a lot of production costs and labor.

  In recent years, efforts have been made to cultivate artificial larvae in various ways on a small or experimental scale.

  Patent Document 1 discloses a culture method in which young shellfish are put in a container laid with sand, covered with a net, and hung in seawater to grow shellfish.

  In this method, the cost for feeding is reduced by entrusting food and the like to the natural environment, and there is an advantage of performing management production by using a container.

  Patent Document 2 discloses a method of cultivating bivalves in a land device with various settings.

  In the method described in Patent Document 2, a grain sand body is laid in the apparatus to a thickness of 3 to 5 times the shell length of a bivalve shell, the water depth is within a range of 0.5 cm to 5 cm, and the breeding water is 1 cm. Injecting at a flow rate within the range of / s to 25 cm / s, a specific adherent microalgae grows on the surface of the grain sand body while adding nutrients, and is cultivated by using it as a feed.

  In this method, the problem of feeding can be solved by breeding adherent microalgae in a container on land, and it can be cultivated under land management.

JP 2008-113649 A

JP 2008-92901 A

  However, in the invention described in Patent Document 1, it is rare that natural larvae to be used are distributed to the market due to restrictions on catch size, etc., so it is necessary to procure artificial larvae separately. If the method becomes widespread, the supply of juvenile shellfish will become an issue in the future.

  In addition, it is necessary to produce a large amount of equipment for aquaculture, and during the breeding period, various maintenance efforts are required at sea. Especially if algae adhere to the container, it is indispensable for the survival of bivalves in the container. It is necessary to periodically lift the equipment out of the water and clean it. Moreover, because it is installed on the sea, the results largely depend on the environment of the sea area, and it is expected that the work cannot be done due to the weather.

  In addition, in the invention described in Patent Document 2, it is necessary to manufacture a special device, and it must be managed within the range of various settings, and an artificial lamp must be installed to further improve the effect. For example, for mass production, the maintenance cost is expected to increase in proportion to the number of devices.

  Moreover, due to water depth, when seawater or brackish water is used, rainwater may enter the equipment installed outdoors, which may cause a drastic drop in salinity and management of breeding water temperature in response to temperature fluctuations. In some cases, additional equipment may be required, and the survival of the contained organisms will be jeopardized if not handled immediately.

  The present invention proposes a method for easily producing submarine bivalves such as clams on land and stably supplying juvenile or adult clams to the market.

The method for producing submarine bivalves such as clams of the present invention includes a useful microorganism such as Bacillus genus, Lactobacillus genus having a purifying action in a breeding pond or breeding tank in which seawater, fresh water or brackish water is used as breeding water. A method for onshore production of clams such as clams by laying medium-grained sand mixed with crushed shells, introducing phytoplankton as feed in the breeding water regularly or irregularly, and housing clams It is characterized by.
That is, it is characterized in that artificially hatched larvae to larvae, or larvae to adult oysters are conveniently and efficiently produced on land consistently.
Examples of useful microorganisms belonging to the genus Bacillus include Bacillus subtilis, Bacillus natto, Bacillus brevis, etc., and in Lactobacillus, Lactobacillus sacilli ), Lactobacillus casei, Lactobacillus plantarum, and the like.

In the method for producing submarine bivalves such as clams of the present invention, when artificial hatching is performed, it is preferable to select a superior mother shell that is not fat and malformed with good growth, and to produce individual larvae by individually collecting eggs. .
By the above, there exists an effect | action which the selection seed | species which is easier to grow is obtained.

  In the method for producing submarine bivalves such as clams of the present invention, bacillus having a purification action for improving sediment quality by using medium-sized sand as the bottom sand in outdoor breeding ponds or breeding tanks (see FIG. 1). By mixing useful microorganisms such as the genus and Lactobacillus and finely crushed shells, the bottom sediment can be brought close to the natural environment, and the components of the crushed shells have the effect of promoting the growth of shells.

  In the method for producing submarine bivalves such as clams according to the present invention, the bottom sand of the outdoor breeding pond or breeding tank is 30 cm ± 5 cm thick. This has the effect of preventing the bottom soil and sand from mixing when the shellfish are dug up.

  In the method for producing submarine bivalves such as clams of the present invention, the water depth of the outdoor breeding pond or breeding tank is in the range of 50 cm to 80 cm. Thereby, the buffer width | variety with respect to the salt concentration fall by rainwater inflow outdoors can be expanded by taking much water quantity.

  In the method for producing submarine bivalves such as clams of the present invention, the water flow toward a certain direction is set in the range of 5 cm / s to 15 cm / s. Thereby, the inside of a pond is stirred and there exists an effect | action which promotes reproduction of a micro algae.

In the method for producing submarine bivalves such as clams according to the present invention, the breeding water inlet is installed at a location far from the drain outlet, the amount of injected water is adjusted according to the amount of rain, and the culture is periodically cultured in the breeding water. By feeding phytoplankton, the feed in the pond is propagated.
According to the above, when seawater or brackish water is used, there is an effect that the decrease in salinity due to rain can be adjusted by injected water, and because it is outdoors, the shellfish can be synthesized by sunlight without using artificial light. Since the phytoplankton serving as the feed can be naturally grown, there is an effect of maintaining a stable feed environment by introducing seed algae once or twice a week.

According to the method for producing submarine bivalves such as clams of the present invention, it grows at the same level as the general case in the natural world, and since it is produced on land, it is easy to harvest and predicts the production amount. Has the effect of making it easier to stand up.
Also, compared to general indoor juvenile production, the management is more extensive, and because it is outdoors, phytoplankton, which serves as a feed by sunlight, propagates naturally in the pond, so production costs can be reduced compared to indoor production. I understood it.

  Since the present invention can be produced in a closed environment, it can be expected to be used for release for resource recovery while preserving the pedigree by collecting seedlings using shellfish in areas where resources have been reduced.

  In addition, juveniles grown up to about 10 mm can be expected to be used for cultured seedling applications, and have the advantage that the size of shellfish can be prepared according to the cultivation form.

  In addition, when grown to adult shellfish, it is possible to record the production history from the local system of the mother shellfish to the content of the feed, and it has the advantage that it can be provided to the market as a safe and secure food that consumers demand.

  The present invention will be described below on the basis of the embodiment of the present invention.

In the present embodiment, the outdoor breeding pond (A) shown in FIG. 1 is a juvenile that has been reared in an indoor aquarium from the seedling process to the transformation process to a juvenile shell, and has been transformed and grown to 350 μm or more, or a natural juvenile shellfish. It is characterized by being raised in.
(A) in FIG. 1 is a plan view of an outdoor breeding pond. A cross-sectional view taken along aa in (A) is (B-1), a cross-sectional view taken along bb is (B-2), and c. A cross-sectional view along -c is (B-3).

  An outdoor aquaculture pond is constructed by surrounding a wall such as a concrete block indicated by 8 in FIG. 1 on a flat place, injecting breeding water from the breeding water injection valve of 6, and water flow by the paddle feel of 3 Wake up in the direction indicated by 4, adjust the water flow in a certain direction with 9 baffle plates, and drain the surplus breeding water from the 5 outlets.

  In carrying out the production technique for submarine bivalves such as clams of the present invention, it is preferable to raise them indoors in order to increase the survival rate until the hatched larvae have settled and transformed into larvae.

  It is desirable to select non-deformed mother shells for seedling and use spermatozoa with high fertilization amount for fertilization.

  Larvae obtained by hatching are reared in an indoor aquarium, and individuals transformed into juveniles that can be attached to the bottom sand are filtered and collected with a 350 μm mesh so that they are uniform on the outdoor rearing pond or the bottom of the rearing tank It is desirable to install in.

  In carrying out the method for producing submarine bivalves such as clams according to the present invention, it is not necessary to prepare special equipment, and particularly in general aquariums, filtration instruments and egg collection tools, and outdoor breeding ponds or breeding tanks. Regardless of the defined shape, the pond is preferably a pond using medium-sized sand mixed with useful microorganisms having a purifying action on the sediment and ground shells, with a drainage function capable of taking a depth of 50 cm or more.

  The method for producing submarine bivalves such as clams according to the present invention includes the introduction of phytoplankton serving as food for the breeding water when raising young larvae in an outdoor breeding pond or breeding tank, In order to prevent the decrease in salt concentration due to rainwater, it is very easy to use only daily management to increase the inflow of seawater.

  The suitable land for carrying out the method for producing submarine bivalves such as clams of the present invention is preferably an environment where seawater, fresh water or brackish water can be used abundantly.

  Although the production method of the present invention is applied to submarine bivalves, submarine bivalves that are resistant to a low salinity state to some extent, such as those that inhabit the vicinity of the river mouth, are preferred. For species inhabiting freshwater or brackish water, it applies to all submarine bivalves that live in rivers and lakes.

  Examples of species that inhabit seawater include clams, clams, red oysters, tiger oysters, and snails. Examples of species that inhabit freshwater or brackish water include masashijimi, setashijimi and yamatoshijimi.

  In outdoor breeding ponds or breeding tanks, it is also possible to combine and culture fish that feed on seaweeds without causing damage to shellfish, for example, mackerel serving as raw food for fishing.

  Examples of the present invention are specifically described below for clams.

Using clams mother shellfish produced consistently at the Ei bivalve cultivation center owned by Minamikyushu City in Beppu, Minamikyushu City, Kagoshima Prefecture, select the fast-growing individuals and use them to collect eggs using non-deformed individuals. The larvae obtained by rearing were cultivated in the outdoor breeding pond shown in FIG. 1 and observed regularly. Egg collection was on April 28, 2008. As a result (Fig. 2), the clam shell length is 10 mm on average for 6 months after egg collection and 22 mm on average for one year, and the production density is 900 individuals / m ² at the 10 mm stage, which is an index for aquaculture larvae. there were. In addition, a large amount of drowning did not occur during the breeding period.

  As described above, the present invention can be used for onshore production of bivalves that inhabit seawater, brackish water, and freshwater bodies.

  Claims described above

It is a schematic diagram of an outdoor breeding pond that produces submarine bivalves such as clams. It is a related figure of the shell length and density measurement result of the clam juvenile produced by this invention, and the general growth density in nature.

1 Sediment mixed with crushed shells and useful microorganisms with cleansing action in medium-sized sand 2 Breeding water 3 Paddle feel 4 Direction of water flow 5 Drain port 6 Breeding water injection valve 7 Water surface of outdoor breeding pond 8 Wall of outdoor breeding pond 9 Current plate 10 Bivalve installed

Claims (7)

  Laying medium-sized sand mixed with useful microorganisms with purifying action and crushed shells in a breeding pond or tank filled with seawater, fresh water or brackish water as breeding water, and regularly or irregularly in the breeding water A land-based production method for submarine bivalves such as clams in which phytoplankton as feed is introduced and juveniles are contained.   Uses medium grain sand as the bottom sand in the breeding pond or the breeding tank, and mixes useful microorganisms such as Bacillus genus, Lactobacillus genus having a purification action for improving the bottom sediment, and finely crushed shells. A method for onshore production of submarine bivalves such as clams according to claim 1.   The method for onshore production of submarine bivalves such as clams according to claim 1, wherein the thickness of the medium grain sand in the breeding pond or the breeding tank is 30c ± 5cm.   The method for onshore production of submarine bivalve such as clams according to claim 1, wherein the depth of water from the water surface of the breeding tank or breeding tank to the surface of the medium grain sand is in the range of 50 cm to 80 cm.   The method for onshore production of submarine bivalves such as clams according to any one of claims 1 to 3, wherein a flow rate of the breeding water is within a range of 5 cm / s to 15 cm / s.   A method for onshore production of submarine bivalves such as clams, characterized by forming a breeding pond on the ground and constantly supplying breeding water with a pump.   A valve is installed in a place far from the drain for the water injected into the breeding pond or the breeding tank, the amount of water is adjusted according to the amount of rain, and cultivated phytoplankton is periodically added to the breeding water. The method for onshore production of submarine bivalves such as clams according to claim 1, wherein the feed is propagated.

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