JP6762262B2 - Shellfish breeding system and shellfish breeding method - Google Patents

Description

The present invention relates to a shellfish breeding system and a shellfish breeding method for breeding shellfish that feed on firefly larvae. More specifically, shellfish are bred on a substantially flat and inclined floorboard, two or more compartments are formed in the area where the shellfish are bred, and the most downstream compartment is provided with a feeding means for juveniles. The present invention relates to a shellfish breeding system and a shellfish breeding method in which an adult shellfish feeding means is arranged in a section on the most upstream side.

Fireflies are very popular because they are popular with people because they emit light and fly at riversides at night. Therefore, for example, many adults and larvae such as Genji firefly and Heike firefly are sold.

In recent years, the number of fireflies inhabiting the natural environment has decreased significantly at the waterside in familiar areas such as satoyama due to the effects of river improvement, cultivated land maintenance, the spread of pesticides, and domestic wastewater. On the other hand, fireflies are sometimes treated as an indicator that the original waterside landscape and environment of the satoyama are maintained, and many attempts have been made to release Genji fireflies and the like outdoors.

Therefore, artificial breeding of fireflies is widely practiced for the sale and release of fireflies.

Fireflies are completely metamorphosing insects that become adults from eggs through the stages of larvae and pupae. For example, in the case of Genji firefly and Heike firefly, the larvae grow in water for about 1 to 2 years after the eggs are laid on the riverbank. After that, around April, they land on riverbanks and dive into the soil to become pupae, and after a pupal period of about 50 days, they become adults from May to June.

In these fireflies, the larvae are aquatic and the larval period is as long as about 1 to 2 years, whereas the adults live on land and can fly using their wings, and the adult period is as short as about 1 to 2 weeks. Therefore, in the artificial breeding of fireflies, the breeding method is completely different between adults and larvae, and the breeding of firefly larvae is one of the extremely important stages.

Among fireflies, for example, Genji firefly larvae feed on Kawanina, and Heike firefly larvae feed on Monoaragai, snail, Kawanina, and the like. Kawanina, which feeds on both Genji firefly and Heike firefly larvae, is a type of snail that belongs to the family Kawanina family. It is known to do. In addition, it is said that an appropriate water flow is required for growth, and it is known that it runs up against the water flow in search of food and flows downstream when the flow velocity exceeds a certain level.

When artificially raising firefly larvae, it is necessary to prepare shellfish to feed on and continue feeding the firefly larvae during the growing period of the firefly larvae. Therefore, artificial breeding of shellfish that feeds on firefly larvae is required. For example, Patent Document 1 describes a method for breeding Kawanina and a water tank for breeding Kawanina as means thereof. In addition, Patent Document 1 also describes that adult shellfish of Kawanina are fed with fallen leaves and pellets that can be eaten in large quantities, and juvenile shellfish are fed with diatoms. In addition, Patent Document 2 describes a method for raising fireflies in which shellfish such as Kawanina, Kawanina's favorite food, and firefly larvae are placed in a net container, and Patent Document 3 describes shellfish that feed on firefly larvae. The method of sorting the parent shell and the juvenile shell and the sorting device are described respectively.
Japanese Unexamined Patent Publication No. 2012-120480 Japanese Patent Application Laid-Open No. 2003-23920 Japanese Unexamined Patent Publication No. 2001-242155

When artificially raising firefly larvae, it is necessary to feed the firefly larvae with shellfish of a size that can be fed by the firefly larvae according to the growth of the firefly larvae. Therefore, it is desirable to always secure shellfish of various sizes.

Therefore, an object of the present invention is to provide a novel breeding means capable of maintaining a state in which various sizes of shellfish, which are used as food for firefly larvae, exist for a long period of time.

The present invention is a shellfish breeding system for breeding shellfish that feed on firefly larvae, in a fixed direction from the upstream side to the downstream side by means of a substantially flat and inclined floor plate and wall plates on both banks. A water channel portion in which a water flow of the breeding water is formed, a storage unit for storing the breeding water that flows down from the downstream side of the water channel portion, and the upstream side of the water channel portion by pumping the breeding water from the storage portion. A water pumping means is arranged in a container, and a plurality of the shellfish are bred in the circulating breeding water on the floor plate of the water channel portion, and a partition member is provided in the water channel portion in a direction of blocking the water flow. By installing the above, two or more compartments are formed in the water channel portion while the circulation is maintained by overflowing the breeding water through the partition member, and the most downstream side of the two or more compartments is formed. A shellfish breeding system or the like in which feeding means for juveniles are arranged in the compartment and at least the feeding means for adult shellfish is arranged in the most upstream side is provided.

In this system, a water channel, a storage, and a pumping means are arranged in the container. Since the floor plate of the water channel portion is inclined, the breeding water flows on the floor plate of the water channel portion in a certain direction from the upstream side to the downstream side, then flows down from the downstream side of the water channel portion, and is stored in the storage portion. The breeding water in the storage portion is supplied to the upstream side of the water channel portion by a pumping means, and the breeding water again flows on the floor plate of the water channel portion in a certain direction from the upstream side to the downstream side. In this way, the circulation of breeding water is maintained in this system, and the water flow in a certain direction is maintained on the floor plate of the channel portion. Then, the floor plate of the waterway portion is used as an area for breeding shellfish, and the shellfish are bred in the circulating breeding water.

In this system, two or more sections are formed in the water channel portion by installing the partition members in the direction of blocking the water flow. Of these, the most downstream section will be the fry breeding section, and the fry feeding means will be placed in that section. On the other hand, one or more compartments on the upstream side are designated as adult shellfish breeding compartments, and adult shellfish feeding means are arranged.

In the juvenile mussel breeding area on the most downstream side, juvenile mussels that have moved voluntarily or have been artificially collected are bred. In the juvenile mussel breeding area, feeding means for juvenile mussels for supplying mussels and the like preferred by juvenile mussels are arranged. Because juvenile mussels prefer juvenile mussels to adult mussels, many juveniles do not voluntarily stay in this compartment and try to improve until they reach a certain size. It grows favorably in the plot.

On the other hand, adult mussels are bred in one or more adult mussels breeding plots on the upstream side. Since the adult mussel breeding plot is provided with a feeding means for adult mussels that supplies artificial mixed feed and the like, the adult mussels grow in this plot.

In addition, since the adult mussel breeding area is formed on the upstream side of the juvenile mussel breeding area, even if an adult mussel of a certain size or larger gets lost in the juvenile mussel breeding area, the breeding water reached from the upstream side. Detects the odor and components of the adult shellfish bait, and performs a run-up action in search of it, and voluntarily moves to the adult shellfish breeding area.

Therefore, by forming a juvenile mussel breeding section and an adult mussel breeding section in the waterway, and arranging the juvenile mussel feeding means in the juvenile mussel breeding section and the adult mussel feeding means in the adult mussel breeding section, the juvenile mussels are arranged. Can be bred separately from adult mussels, which can greatly increase the survival rate of juvenile mussels. By improving the survival rate of juveniles, the total number of individuals will increase as the juveniles grow, which will enable highly efficient production of shellfish.

In adult mussels breeding plots, adult mussels routinely produce juvenile mussels. These juveniles are voluntarily moved to the juvenile breeding plot or artificially moved to the juvenile breeding plot. As described above, juvenile mussels prefer the juvenile mussel diet to the adult mussel diet, so they stay in the juvenile mussel breeding area and grow. After that, when it grows to a certain size, it comes to prefer the adult shellfish food, detects the odor and components of the adult shellfish food that arrived from the upstream side, and voluntarily seeks it. Move to the adult shellfish breeding area. Therefore, on the basis that the overall population can be maintained high by improving the survival rate of juveniles, as an overall tendency, shellfish of the size according to the growth stage are divided in order from the downstream side to the upstream side. It will be distributed in each area, and it is possible to maintain the existence of shellfish of various sizes. That is, according to the present invention, it is possible to maintain the population while increasing the number of breeding individuals, and it is possible to maintain the distribution composition of each size in the population in a state of less bias.

This makes it possible to feed firefly larvae with various sizes of shellfish according to the growth of the firefly larvae, for example, when artificially breeding firefly larvae.

According to the present invention, it is possible to maintain the existence of various sizes of shellfish that feed on firefly larvae.

<About the shellfish breeding system according to the present invention>
The present invention is a shellfish breeding system for breeding shellfish that feed on larvae of fireflies, in a fixed direction from the upstream side to the downstream side by means of a substantially flat and inclined floor plate and wall plates on both banks. A water channel portion in which a water flow of the breeding water is formed, a storage unit for storing the breeding water that flows down from the downstream side of the water channel portion, and the upstream side of the water channel portion by pumping the breeding water from the storage portion. A water pumping means is arranged in a container, and a plurality of the shellfish are bred in the circulating breeding water on the floor plate of the water channel portion, and a partition member is provided in the water channel portion in a direction of blocking the water flow. By installing the above, two or more compartments are formed in the water channel portion while the circulation is maintained by overflowing the breeding water through the partition member, and the most downstream side of the two or more compartments is formed. The compartment includes all shellfish breeding systems in which juvenile feeding means are provided and at least the most upstream compartment is provided with adult shell feeding means. An example thereof will be described below with reference to FIGS. 1 and 2. The present invention is not narrowly limited to the following embodiments.

FIG. 1 is a schematic external perspective view showing an example of the shellfish breeding system according to the present invention, and FIG. 2 is a schematic cross-sectional view with respect to the breeding water flow direction. It should be noted that both figures are separate examples, and the configurations of both figures are not all correlated.

In the shellfish breeding system A of FIGS. 1 and 2, the water flow of the breeding water W in a certain direction from the upstream U side to the downstream D side by the substantially flat and inclined floor plate 11 and the wall plates 12 and 13 on both banks ( Water channel 1 where (codes X1 to X5) are formed, storage section 2 that stores breeding water W (see code X6) that flows down from the downstream D side of water channel 1, and breeding water W is pumped from storage section 2. A pumping means 3 (see reference numeral X7) that supplies water to the upstream U side of the water channel 1 is arranged in the container B, and a plurality of shellfish S1 to S3 are bred on the floor plate 11 of the water channel 1 to the water channel 1. By installing the partition members 41 and 42 in the direction to block the water flows X1 and X3, the breeding water W overflows the partition members 41 and 42 to maintain the circulation (see the symbols X2 and X4). Three compartments (large adult shellfish breeding compartment R1, medium-sized adult shellfish breeding compartment R2, juvenile shellfish breeding compartment R3) are formed in Part 1, and among these compartments, large adult shellfish breeding compartment R1 and medium-sized adult shellfish breeding compartment R1 Adult mussels feeding means 51 and 52 are arranged in R2, respectively, and juvenile mussels feeding means 51 are arranged in the most downstream juvenile mussel breeding section R3. A juvenile mussel fall prevention member 6 is installed at or near the downstream D end of the waterway portion 1 in a direction to block the water flow, and the wall plate 13 separating the large adult mussel breeding compartment R1 and the juvenile mussel breeding compartment R3 is juvenile. A passage hole 14 having a size that allows shellfish to pass through is formed. A lid B1 is provided on the upper edge side of the container B. In addition, as shown in FIG. 2, a light irradiation means L is provided in the storage unit 2.

The breeding water W (W1 to W3) first flows on the floor plate 11 from the upstream U side of the waterway portion 1 (see reference numeral X1), and stays at a height h1 by the partition member 41 (reference numeral W1), while the partition member 41 (See code X2) and flow into the medium-sized adult mussel breeding plot R2. Next, after turning the water flow direction in the medium-sized adult mussel breeding compartment R2 (see reference numeral X3), the partition member 42 overflows while the water is stagnant by the partition member 42 (see reference numeral X4), and then the juvenile mussel breeding compartment R3 Flow into. Next, it flows on the floor plate 11 of the juvenile mussel breeding compartment R3 (see reference numeral X5), stays at a height of h3 by the juvenile mussel fall prevention member 6 (reference numeral W2), and overflows the juvenile mussel fall prevention member 6 (reference numeral W2). (See code X6), flowing down to the reservoir 2. Then, the breeding water W3 stored in the storage section 2 is supplied to the upstream U side of the water channel section 1 by the pumping means 3 (see reference numeral X7). In this way, the circulation of the breeding water W is maintained in the system A (reference numerals X1 to X7), and the water flow in a certain direction is maintained on the floor plate 11 of the waterway portion 1.

The shellfish breeding system A according to the present invention is widely applicable to the breeding of shellfish that feed on firefly larvae. For example, it can be applied to the breeding of freshwater shellfish such as Kawanina, which is a food for Genji firefly and Heike firefly larvae, and Monoaragai and Snail, which are food for Heike firefly larvae.

The container B is a container used as a breeding tank for shellfish S (S1 to S3), and for example, a box-shaped container with an open top and a bottom can be widely adopted. The shape is not particularly limited as long as the water channel portion 1, the storage portion 2, and the pumping means 3 can be appropriately arranged inside. Further, the side wall / bottom surface of the container B or a portion thereof may be used as the wall plate of the water channel portion 1 and the bottom surface / side surface of the storage portion 2. For the container B, for example, a box or a case having a substantially rectangular parallelepiped shape or a substantially tubular shape can be appropriately adopted. Further, the material such as the container B is not particularly limited as long as it can be formed so as not to leak water in the water channel portion 1 and the storage portion 2.

A lid B1 may be provided on the upper edge of the container B. For example, of the inner wall surface of the container B, a lid portion B1 formed substantially vertically from the inner wall surface over the region at or near the upper edge of the portion forming the wall plate 12 of the water channel portion 1. By allowing the shellfish to be placed on the upper edge of the container B, the shellfish can be effectively prevented from escaping to the outside of the container B by functioning like a rat guard. The lid portion B1 may substantially cover the entire upper surface of the container B, for example, and as shown in FIG. 1, covers only the peripheral side of the upper surface of the container B and opens the central side. It may be the one that is.

The water channel 1 is a part where a water flow of breeding water W in a certain direction is formed. For example, like a three-sided water channel, the floor plate 11 and the wall plates 12 and 13 on both banks have a substantially U-shaped cross section. A portion through which the breeding water W flows is formed, and the breeding water W is formed so as to flow in a certain direction on the floor plate 11 between the wall plates 12 and 13 on both banks.

The floor plate 11 of the water channel portion 1 is formed of a substantially flat plate-like member, and the floor plate 11 serves as a portion through which the breeding water W flows in a certain direction and also serves as a region for breeding shellfish.

By forming the floor plate 11 at an angle, the breeding water W can flow in a certain direction. The inclination angle can be appropriately set and is not particularly limited, but may be set to, for example, about 1 to 20 °.

The wall plates 12 and 13 of the water channel 1 are members forming both banks of the water channel 1. For example, both members are erected from the floor plate 11 in the substantially vertical direction along the flow direction of the breeding water W. As a result, the breeding water W flows between the two members, and the flow direction is defined. One or both of the wall plates 12 may be formed on the side wall of the container B.

As the material of the floor plate 11 and the wall plates 12 and 13, for example, known plate materials such as acrylic resin, polyvinyl chloride resin, polycarbonate resin, and glass can be widely used.

The storage portion 2 is a portion for storing the breeding water W from the time when the water flows down from the downstream D side of the water channel portion 1 until the water is pumped by the pumping means 3.

In this system A, the circulation of the breeding water W in a certain direction is maintained, so that the feces and residual food of the shellfish S can be collected in the storage part 2 relatively easily, thereby, and the waterway part 1 The inside can be kept relatively clean. Therefore, cleaning and maintenance of this system A and breeding management of shellfish S can be simplified and labor-saving.

The members constituting the storage unit 2 may be formed so as not to leak water, and the material thereof is not particularly limited. Further, the side wall / bottom surface of the container B or a portion thereof may be used as the bottom surface / side surface of the storage unit 2. As the material of the storage unit 2, for example, the same materials as those of the floor plate 11 and the wall plates 12 and 13 may be adopted.

The pumping means 3 is a portion where the breeding water W is pumped from the storage portion 2 and supplied to the upstream U side of the water channel portion 1 (see reference numeral X7). As the pumping means 3, a known pump such as a pump can be widely adopted, and the pumping means 3 is not particularly limited.

In FIGS. 1 and 2, three compartments (large adult shellfish breeding compartment R1, medium-sized adult shellfish breeding compartment R2, and juvenile shellfish breeding compartment R3) are formed in the waterway portion 1 by the partition members 41 and 42.

The partition members 41 and 42 are members that separate the inside of the water channel portion 1 into two or more sections, and are installed in directions to block the water flow. For example, it is formed of plate pieces of approximately the same length as between the wall plates 12 and 13 on both banks, and on the floor plate 11 in a direction approximately orthogonal to the water flow direction, both ends are on the wall plates 12 and 13 on both banks, respectively. Install so that it can be reached. In addition, the heights of the partition members 41 and 42 (height from the floor plate 11 at the time of installation, see reference numeral h1 in FIG. 2) are set so that the breeding water W stays to some extent and then overflows. To do.

By installing the partition members 41 and 42, the inside of the water channel 1 is separated into two or more sections, and the floor plate 11 of the water channel 1 is inclined, so that the partition members 41 and 42 are upstream (FIG. 1). In the case of FIG. 2 and FIG. 2, a retention area of breeding water W corresponding to the height of the partition members 41 and 42 is formed in the large adult shellfish breeding compartment R1 and the medium-sized adult shellfish breeding compartment R2). In addition, after the breeding water W stays, it overflows and flows in the downstream D direction, so that the circulation of the breeding water W is maintained.

The partition members 41 and 42 may be detachably formed. The partition members 41 and 42 are detachably formed, and for example, by temporarily removing the partition members 41 and 42 during cleaning, the feces and residual food of the shellfish generated and stored in the waterway 1 can be removed by a stream of water. Feces and residual food can be washed away with a stream of water, and the labor required for cleaning, maintenance, and management of this breeding system A can be reduced.

In addition, for example, a net material having a mesh size that allows shellfish S of a predetermined size or smaller to pass may be installed near the installation locations of the partition members 41 and 42 in a direction that blocks the water flow. As a result, depending on the size of each mesh of each net material, for example, the large shellfish S1 is moved to the medium-sized adult shellfish breeding compartment R2, further to the juvenile shellfish breeding compartment R3, and the medium-sized shellfish S2 is moved to the juvenile shellfish breeding compartment R3. You can more surely prevent the movement to. Specifically, for example, it is possible to prevent the shellfish S having a size equal to or larger than a predetermined size from moving over the partition members 41 and 42 to the downstream side. Further, for example, when the partition members 41 and 42 are temporarily removed, it is possible to prevent the shellfish S having a size larger than a predetermined size from moving to the downstream side due to the water flow.

Adult shellfish breeding compartments R1 and R2 (large adult shellfish breeding compartment R1 and medium-sized adult shellfish breeding compartment R2) are areas where adult shellfish S1 and S2 are mainly bred, and are located on the upstream U side of the juvenile shellfish breeding compartment R3. To do.

Adult mussels feeding means 51 and 52 are arranged in the adult mussels breeding compartments R1 and R2. In general, adult mussels have a stronger appetite than juvenile mussels and eat algae that juvenile mussels prefer, but prefer artificially mixed feed (feed pellets), vegetables, and fallen leaves. On the other hand, if there is enough food for those adult mussels S1 and S2, they generally stay in the plot. Therefore, feeding means 51 and 52 for adult mussels that feed the foods preferred by those adult mussels S1 and S2 are arranged in the adult mussels breeding compartments R1 and R2, and the adult mussels S1 and S2 are bred in the compartments. As the feed to be fed to the adult shellfish S1 and S2, known feeds such as artificial compound feed (feed pellets), vegetables, and fallen leaves are adopted.

The juvenile mussel breeding section R3 is an area for breeding juvenile mussels S3, and is arranged on the most downstream D side of the waterway portion 1.

A fry feeding means 53 is arranged in the fry breeding section R3. As a result of the observations by the present inventors, the juvenile mussel S3 prefers to eat algae with almost no feeding of artificial compound feed (feed pellets), vegetables, fallen leaves and the like. Therefore, a fry feeding means 51 for feeding the fry S3's favorite food is arranged in the fry breeding section R3, and the fry S3 is bred in the section. As the bait to be fed to the juvenile mussel S3, for example, algae preferred by the juvenile mussel S3 such as oyster algae are adopted.

For example, the juvenile mussel feeding means 51 may be an algae-attached base, and the algae grown on the base may be fed. By using the base on which the algae are attached as the feeding means 53 for juvenile mussels and installing the base in the juvenile mussel breeding compartment R3, the juvenile mussels S3 feed on the algae attached and propagated on the base.

The base material of the algae adhesion base may be any member as long as it can adhere to algae, and is not particularly limited. For example, a base material having irregularities or gaps of 0.3 mm or less on the surface may be used for the base material.

For example, by using a base material for the algae adhesion base, which has irregularities formed on the surface of a plastic flat plate and the groove width of the irregularities is 0.3 mm or less, the groove width is larger than the size of the mouth of the juvenile mussel S3. Even after the juvenile mussel S3 feeds on the algae on the basement, the algae in the ditch can be left without being consumed.

Similarly, by using a base material having a gap of 0.3 mm or less, such as a plastic net material, artificial turf, or corrugated sheet, as the base material of the algae adhesion base, the juvenile mussel S3 feeds the algae on the base. Even after feeding, the algae in the gaps in the material can be left without being consumed.

Then, for example, after arranging the light irradiation means L capable of irradiating a predetermined position in the storage unit 2 with light in the container B, the algae attachment base after feeding by the juvenile S3 is placed in the storage unit 2. The attached algae are regenerated by irradiating the storage unit 2 with light by the light irradiation means L.

As a result, in addition to being able to effectively utilize the space of the storage unit 2, it is possible to reproduce the algae adhesion base in the container B and to reuse the base. In addition, since nitrogen, phosphorus, etc. contained in the feces and residual food of shellfish S are used in the process of algae growth, the algae attachment base after feeding of juvenile shellfish S3 is housed in the reservoir 2 and its By reproducing the attached algae, the circulating breeding water W is purified. Therefore, the number of times the circulating breeding water W is changed can be reduced, and cleaning and maintenance of the system A can be simplified and labor can be reduced. In addition, the labor of water quality management of breeding water W can be reduced.

The juvenile mussel fall prevention member 6 is a member for preventing the juvenile mussel S3 from falling from the juvenile mussel breeding section R3 formed on the most downstream D side of the waterway portion 1 (on the floor plate 11) to the storage portion 2. Yes, it is installed at or near the downstream end of the channel 1 in a direction that blocks the water flow. For example, similar to the partition members 41 and 42, it is formed of a plate piece having substantially the same length as the wall plates 12 and 13 on both banks, and both ends are formed on the floor plate 11 in a direction substantially orthogonal to the water flow direction. Install so that it almost reaches the wall boards 12 and 13 on the shore. In addition, the height of the juvenile mussel fall prevention member 6 (height from the floor plate 11 at the time of installation, see the symbol h2 in FIG. 2) is set so that the breeding water W overflows after staying to some extent. Set.

Since the floor plate 11 of the water channel 1 is inclined, by installing the juvenile mussel fall prevention member 6, the juvenile mussel fall prevention member 6 is located upstream of the partition members 41 and 42 (FIGS. 1 and 2). In the case of, a retention area of breeding water W corresponding to the height of the juvenile mussel fall prevention member 6 is formed in the juvenile mussel breeding section R3). Further, after the breeding water W stays, the breeding water W is circulated because it overflows the juvenile clam fall prevention member 6 and flows down to the storage unit 2.

For example, a juvenile mussel fall prevention member 6 is installed at or near the downstream D end of the waterway portion 1 in a direction to block the water flow, and the breeding water W overflows the juvenile mussel fall prevention member 6 and stores the mussel. The height of the juvenile clam fall prevention member 6 from the floor plate 11 is set lower than the height of the partition member (reference numeral 41 and / or 42) from the floor plate 11 as it flows down to the portion 2 (see reference numeral X6). May be configured.

For example, when the height of the juvenile mussel fall prevention member 6 from the floor plate 11 is set lower than the height of the partition member 41 on the most upstream U side from the floor plate 11, the breeding water W2 staying in the juvenile mussel breeding compartment R3. The water level height (the same height as the symbol h2) can be made lower than the water level height (the same height as the symbol h1) of the breeding water W1 staying in the large adult shellfish breeding compartment R1. According to the observations of the present inventors, in general, adult mussels S1 tended to prefer deeper waters than juvenile mussels S3, and juvenile mussels S3 tended to prefer shallower waters than adult mussels S1. .. Therefore, by setting the height of the juvenile clam fall prevention member 6 lower than the height of the partition member 41, etc., it is possible to create a breeding environment that matches the size of the body in each of the compartments R1 and R3. By actively moving the juvenile mussels S3 to the juvenile mussels breeding compartment R3, the tendency of adult mussels S1 (S2) and juvenile mussels S3 to segregate in each compartment R1 and R3 is further promoted according to the size of the body. it can.

The juvenile clam fall prevention member 6 may be detachably formed like the partition members 41 and 42. The juvenile fall prevention member 6 is detachably formed, and by temporarily removing the juvenile fall prevention member 6 at the time of cleaning, for example, the feces and residual food of shellfish generated and stored in the water channel 1 can be discharged. It can be flushed to the storage section 2 and the cleaning, maintenance, and management of this breeding system A can be reduced.

In this system A, for example, when breeding of adult mussels S1 and S2 is started in adult mussels breeding compartments R1 and R2 (large adult mussels breeding compartment R1 and medium-sized adult mussels breeding compartment R2) at the introduction stage, adult mussels S1 and S2 Under the circulating water flow, while feeding the food supplied from the feeding means 51 and 52 for adult mussels, it stays in the same section R1 and R2, grows well, and routinely feeds the juvenile mussels S3. Start producing.

The produced juvenile mussels S3 are lighter than the adult mussels S1 and S2. Therefore, for example, when cleaning, the partition members 41 and 42 are temporarily removed and the breeding water W is poured with an appropriate strength. , Adult mussels S1 and S2 generally stay in the adult mussels breeding compartments R1 and R2, while the juvenile mussels S3 are washed away and moved to the juvenile mussels breeding compartment R3. In addition, the juvenile mussels S3 in the large adult mussel breeding compartment R1 and the medium-sized adult mussel breeding compartment R2 may be artificially moved to the juvenile mussel breeding compartment R3.

Further, for example, by turning the water flow direction of the water channel (see reference numeral X3), the most downstream D-side compartment R3 and the most upstream U-side compartment R1 are adjacent to each other, and the two compartments R1 and R3 are separated from each other. A passage hole 14 having a size that allows the juvenile mussel S3 to pass through is formed in the wall plate 13, and the juvenile mussel S3 descends along the water channel by passing through the passage hole 14 (reference numerals X1 to X5). It may be configured so that it can be directly moved from the most upstream U-side compartment R1 to the most downstream D-side compartment 3 without (see).

According to the observations of the present inventors, the juvenile mussels S3 (produced in the adult mussels breeding compartment R1 etc.) are more than the adult mussels S1 and S2 because the food preferred by the juvenile mussels S3 is not sufficient in the same compartments R1 and R2. Also tends to move around aggressively. Therefore, when a passage hole 14 having a size that only the juvenile mussel S3 can pass through is formed in the wall plate 13, many juvenile mussels S3 voluntarily pass through the passage hole 14 in search of the food preferred by the juvenile mussel S3. Then, it moves to the juvenile clam breeding compartment R3, and then stays in the same compartment R3. On the other hand, since the adult mussel S1 cannot pass through the passage hole 14, it continues to grow in the adult mussel breeding section R1 and the like.

In the water channel portion 1, how to turn the water flow direction of the water channel can be widely adopted, and is not particularly limited. For example, as shown in FIG. 1, in a container B having a substantially rectangular parallelepiped, the water flow direction of the water channel may be swirled by folding back the water channel portion in a straight line or a polygonal line, or at least by forming the swivel portion in a curved line. The water flow direction of the water channel may be swiveled.

In this way, after the produced juvenile mussels S3 are voluntarily moved to the juvenile mussels breeding compartment R3 or artificially moved to the juvenile mussels breeding compartment R3, the juvenile mussels S3 are more than the adult mussels feed. Because it prefers food for juveniles, it stays in the juvenile breeding area R3 and grows. As a result, the juvenile mussels S3 can be bred substantially isolated from the adult mussels S1 and S2, so that the survival rate of the juvenile mussels S3 can be significantly improved.

After that, when the juvenile mussel S3 grows to a certain size, it comes to prefer the adult mussel food, detects the odor and components of the adult mussel food that arrived from the upstream U side, and detects it. In search of it, it overcomes the partition member 42 and voluntarily moves to the medium-sized adult shellfish breeding compartment R2.

The medium-sized adult mussels S2 that moved and settled in the medium-sized adult mussels breeding compartment R2 grew in the same compartment R2, and some individuals who felt that there was insufficient food were for adult mussels in the breeding water that arrived from the upstream U side. It detects the odor and components of food, seeks it, overcomes the partition member 41, and voluntarily moves to the large adult shellfish breeding section R1 further upstream. In this way
As a general tendency, shellfish of the size according to the growth stage will be distributed in each section in order from the downstream side to the upstream side.

As described above, in this system A, the juvenile mussels S3 are bred substantially isolated from the adult mussels S1 and S2, and in the juvenile mussels breeding section R3, the juvenile mussels S3 are fed with the food preferred by the juvenile mussels S3. The survival rate can be greatly improved. In addition, the overall population can be maintained high by improving the survival rate of juvenile mussels S3. Furthermore, while increasing the number of breeding individuals, the distribution composition for each size in the population can be maintained in a state of less bias.

<About the shellfish breeding method according to the present invention>
The present invention is a shellfish breeding method for breeding shellfish that feed on firefly larvae, including a shellfish breeding method using the above-mentioned shellfish breeding system, which is a substantially flat and inclined floor plate and both banks. A water channel portion in which a water flow of breeding water in a certain direction from the upstream side to the downstream side is formed by the wall plate, a storage portion for storing the breeding water flowing down from the downstream side of the water channel portion, and the breeding water. A water pumping means for pumping water from the storage portion and supplying it to the upstream side of the water channel portion is arranged in a container, and a plurality of the shellfish are bred in the circulating breeding water on the floor plate of the water channel portion. By installing a partition member in the water channel portion in a direction that blocks the water flow, the breeding water overflows the partition member to maintain the circulation and form two or more compartments in the water channel portion. However, among the two or more compartments, the most downstream compartment is provided with the feeding means for juveniles, and at least the most upstream compartment is provided with the feeding means for adult shellfish. To do.

As described above, a breeding environment that circulates breeding water is created, two or more compartments are formed on the floor plate of the waterway, and juvenile mussels are bred roughly isolated from adult mussels, and juveniles are bred in the most downstream compartment. By feeding the shellfish's favorite diet, the survival rate of juvenile clams can be significantly improved, and as a result, the total population can be maintained high. In addition, since each section is continuous on the floor plate of the waterway and the section for growing juvenile mussels is formed on the most downstream side, as the juvenile mussels grow, the upstream where the adult mussels prefer food. It is possible to move voluntarily to the side compartment. As a result, the distribution composition of each size in the population can be maintained in a state with little bias while increasing the number of breeding individuals.

In Example 1, the survival rate of juvenile mussels was compared between the case where adult mussels and juvenile mussels were bred in the aquarium and the case where only juvenile mussels were bred.

Prepare two plastic containers of the same size, put 1 L of breeding water in each, put 3 adult Kawanina and 30 juveniles in one, and 30 juveniles in the other for 28 days. , Raised in a dark room.

During the breeding period, the water temperature was adjusted to 20 ± 1 ° C. As feed, a commercially available artificial compound feed (feed pellet) is fed once a week, and a commercially available plastic net is placed in another Kawanina breeding aquarium, and oyster algae are attached to it during the breeding period. It was placed in a container as an algae attachment base.

The results are shown in Figure 3. FIG. 3 is a graph showing the survival rate of juvenile mussels when only juvenile mussels are bred in the aquarium. In Fig. 3, the vertical axis shows the survival rate of juvenile mussels, and the bar graph representing "1" shows the survival rate of juvenile mussels when only juveniles are bred in the aquarium. As a comparative example, the survival rate of juvenile mussels when adult mussels and juvenile mussels are bred at the same time in an aquarium is shown.

As a result, as shown in Fig. 3, when adult and juvenile mussels were bred at the same time in the aquarium, the survival rate of the juvenile mussels was 17%, whereas when only juvenile mussels were bred in the aquarium, The survival rate of juvenile mussels was 71%.

This result indicates that the survival rate of juvenile mussels can be significantly improved by raising juvenile mussels isolated from adult mussels while feeding mussels.

In Example 2, the shellfish breeding system according to the present invention was constructed and Kawanina was bred.

A shellfish breeding system with the same structure as in Fig. 1 was prototyped. Acrylic resin plate materials were appropriately molded, arranged, and bonded to a container measuring 420 mm in length, 650 mm in width, and 250 mm in height to form a water channel and a storage part, and a submersible pump was installed as a pumping means. A partition member was formed from an acrylic resin plate material, and the waterway section was divided into three sections, which were used as a large adult shellfish breeding section, a medium-sized adult shellfish breeding section, and a juvenile shellfish breeding section, respectively. In the large adult mussel breeding area and the medium-sized adult mussel breeding area, a feeding unit for feeding commercially available artificial compound feed (feed pellets) is installed as a feeding means for adult shellfish, and the artificial compound feed is provided three times a week during the breeding period. Was replenished. As a feeding means for juvenile mussels, plastic nets with oyster algae attached were placed in the juvenile mussels breeding plot. At the same time, as a means of feeding for juvenile mussels for replacement, a separate plastic net was placed in the breeding water stored in the storage section and irradiated with LED lights for 8 hours a day during the breeding period to grow periphyton. .. During the breeding period, the feeding means for juvenile mussels was replaced with the one grown in the reservoir as appropriate.

About 15 L of breeding water was added and pumped at 600 L / hour with a submersible pump to circulate the breeding water. During the breeding period, the evaporated water in the breeding water was appropriately replenished.

Twelve Kawanina with a shell height of 20 mm or larger were housed in the large adult shell breeding plot of this prototype system, and 60 Kawanina with a shell height of 8 to 20 mm were housed in the medium-sized adult shell breeding plot, and breeding was started.

When the partition member is temporarily removed for cleaning, the produced juveniles are moved from the large adult or medium-sized adult mussels to the juvenile mussels by the flow of breeding water, and also large. They voluntarily moved from the passage holes formed in the wallboard that separates the adult and juvenile mussels, and artificially moved the others to the juvenile mussels.

The results are shown in Tables 1 and 2. Table 1 shows the number of individuals in each plot at each breeding day, and Table 2 shows the survival rate of juvenile mussels at each breeding day.

As shown in Tables 1 and 2, a large number of juvenile mussels were produced from a total of 72 adult Kawanina mussels in the large adult mussel breeding plot and the medium-sized adult mussel breeding plot 30 days after the start of breeding, 60% of which. Survived. Even 60 to 120 days after the start of breeding, the survival rate of juvenile mussels was maintained in the range of 50 to 60%, and the increasing tendency of the number of individuals in the juvenile mussels breeding plot was also maintained. In this way, by using the shellfish breeding system according to the present invention, the number of dead mussels and the number of newly produced mussels are kept increasing, and in the mussels breeding plot. We were able to raise juveniles in a good and stable manner.

In the juvenile mussel breeding plot, 5 individuals had a shell length of 2.5 to 6.0 mm 30 days after the start of breeding, and those with a shell length of 2.5 to 6.0 mm 60 days after the start of breeding. 168 individuals, 13 individuals with a shell length of 6.1 to 10 mm, 247 individuals with a shell length of 2.5 to 6.0 mm and a shell length of 6.1 to 10 mm 90 days after the start of breeding. 33 individuals were observed to have grown to, 246 to have a shell length of 2.5 to 6.0 mm, and 45 to have a shell length of 6.1 to 10 mm 120 days after the start of breeding. .. As described above, in the juvenile mussel breeding plot, the number of individuals whose shell length has increased with the lapse of breeding days is increasing, and by using the shellfish breeding system according to the present invention, juvenile mussels can be satisfactorily produced in the juvenile mussel breeding plot. I was able to grow and grow.

As shown in Table 1, in the large adult mussel breeding plot, until 120 days after the introduction of 12 Kawanina individuals at the start of breeding, and in the medium-sized adult mussel breeding plot, 90 days after the introduction of 60 Kawanina individuals at the start of breeding. Until then, its population has decreased slightly. This was mainly due to the fact that some of the individuals introduced at the start of breeding died as a result of observation.

On the other hand, in the medium-sized adult mussel breeding plot, the number of individuals increased during the breeding days of 90 to 120 days. This increase was presumed to be due to the fact that individuals that grew to a shell length of about 10 mm in the juvenile mussel breeding plot voluntarily moved from the juvenile mussel breeding plot to the medium-sized adult mussel breeding plot. Based on this estimation, in the shellfish breeding system according to the present invention, when the shellfish to be bred grows to a certain size, it spontaneously moves from the juvenile mussel breeding plot to the adult mussel breeding plot, so that it continues to grow. There is a high possibility that shellfish of the size according to the stage can be bred in each section.

The external perspective schematic diagram which shows the example of the shellfish breeding system which concerns on this invention. FIG. 6 is a schematic cross-sectional view showing an example of the shellfish breeding system according to the present invention with respect to the breeding water W flow direction. In Example 1, the graph which shows the survival rate of the juvenile mussel when only the juvenile mussel was bred in the aquarium.

1 Waterway
11 Floor board
12, 13 wallboard
14 passage hole
2 Reservoir
3 Pumping means
41, 42 Partition member
51, 52 Feeding means for adult shellfish
53 Feeding means for juvenile clams
6 Young shellfish fall prevention member
A Shellfish breeding system
B container
B1 lid
D Downstream of waterway 1
R1 Large adult shellfish breeding area
R2 Medium-sized adult shellfish breeding plot
R3 juvenile clam breeding area
S1, S2 adult shellfish
S3 juvenile shellfish
Upstream of U Channel 1
W (W1 to W3) Breeding water

Claims (7)

A shellfish breeding system for breeding shellfish that feed on firefly larvae.
A channel portion in which a flow of breeding water in a certain direction from the upstream side to the downstream side is formed by a substantially flat and inclined floor plate and wall plates on both banks, and the breeding water flowing down from the downstream side of the channel portion. A storage unit for storing and a pumping means for pumping the breeding water from the storage unit and supplying the breeding water to the upstream side of the water channel portion are arranged in the container.
A plurality of the shellfish are bred in the circulating breeding water on the floor plate of the waterway portion.
By installing a partition member in the waterway portion in a direction that blocks the water flow, the breeding water overflows the partition member to maintain the circulation, and two or more compartments are formed in the waterway portion. Being done
A shellfish breeding system in which a fry feeding means is provided in the most downstream section of the two or more sections, and an adult feeding means is provided in at least the most upstream section. The shellfish breeding system according to claim 1, wherein the feeding means for juveniles is an algae-attached base, and the algae grown on the base are fed. The shellfish breeding system according to claim 1 or 2, wherein a base material having irregularities or gaps of 0.3 mm or less on the surface is used for the base material. Claim 2 or claim 3 for reproducing the attached algae by accommodating the algae-attached base after feeding by the juveniles in the reservoir and irradiating the reservoir with light by a light irradiation means. The described shellfish breeding system. A juvenile mussel fall prevention member is installed at or near the downstream end of the water channel portion in a direction to block the water flow.
The breeding water overflows the juvenile clam fall prevention member and flows down to the storage portion.
The shellfish breeding system according to any one of claims 1 to 4, wherein the height of the fry fall prevention member from the floor plate is set lower than the height of the partition member from the floor plate. By turning the water flow direction of the water channel, the most downstream side section and the most upstream side section are adjacent to each other, and the wall plate separating the two sections has a passage hole having a size that allows the juvenile clams to pass through. Is formed,
Claim 1 that the juvenile mussels can directly move from the most upstream side section to the most downstream side section by passing through the passage hole without descending along the waterway. The shellfish breeding system according to any one of ~ 5. It is a shellfish breeding method for breeding shellfish that feed on firefly larvae.
A channel portion in which a flow of breeding water in a certain direction from the upstream side to the downstream side is formed by a substantially flat and inclined floor plate and wall plates on both banks, and the breeding water flowing down from the downstream side of the channel portion. A storage unit for storing and a pumping means for pumping the breeding water from the storage unit and supplying the breeding water to the upstream side of the water channel portion are arranged in the container.
A plurality of the shellfish are bred in the circulating breeding water on the floor plate of the waterway portion.
By installing a partition member in the waterway portion in a direction that blocks the water flow, the breeding water overflows the partition member to maintain the circulation and form two or more compartments in the waterway portion. And
A shellfish breeding method in which a fry feeding means is provided in the most downstream section of the two or more sections, and an adult feeding means is provided in at least the most upstream section.

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