JP5166308B2 - Bivalve floating larva rearing method and control device thereof - Google Patents

Description

  The present invention relates to a bivalve floating larva breeding method and a control apparatus thereof capable of high density floating larva breeding of bivalves in general such as oysters and pearl oysters.

  Conventionally, breeding of bivalves such as oysters and pearl oysters is well known (see, for example, Patent Document 1 and Patent Document 2). Such bivalve breeding is carried out, for example, by breeding bivalve floating larvae at a high density of several tens of pieces / ml or more by a floating breeding method.

  In such a floating breeding method, floating larvae of bivalves are accommodated in a single breeding tank, and seawater (breeding water) pumped up by a pump is allowed to flow into the breeding tank. And the breeding water in a breeding aquarium is discharged | emitted after filtering with the filter provided in the breeding aquarium.

JP 2002-186376 A JP 2004-357603 A

  In conventional floating-type bivalve floating larva breeding, clogged filters due to larval feces (excrement), dirt in the rearing tank, residual food settled on the bottom and dead dead larvae (moribund shellfish) Cleaning work such as removal is necessary. In this operation, the entire water is changed as appropriate, and the breeding water tank and the filter are washed.

  When total replacement of breeding water is performed, it is desirable to separate vigorous floating larvae from residues such as excrement and moribund shellfish. However, under the present circumstances, a method is adopted in which a fullerium with a plankton net attached to the bottom is used to receive the total amount of breeding water. In this way, the method of receiving the total amount of breeding water damages floating larvae, and in many cases residues such as excrement and moribund shellfish are mixed in the floating larvae, reducing the vitality and survival rate of floating larvae. There is a risk.

  In addition, when cleaning aquariums and filters, it is necessary to increase the frequency of washing as the amount of excreta increases. In particular, clogging due to dirt on the filter reduces the discharge of breeding water. There is a risk of overflowing from overflow.

  Such work is performed manually, and there is a problem that the burden on the worker increases as the work frequency increases.

  The present invention is to raise the floating larvae of bivalve in general with high density and high efficiency by removing residues such as excrement, moribund shellfish and residual food at the bottom of the aquarium without mixing them with the floating larvae being raised. The first problem is to be able to do this.

  Moreover, it is a 2nd subject to be able to perform washing | cleaning of a breeding water tank and a filter without a restriction | limiting in man-hour working time.

  The present invention has been made in order to solve the above-mentioned problems, and the feature of the bivalve floating larva breeding method is that fresh water is supplied to a breeding aquarium in which breeding water is stored, and the breeding water is supplied through a filter. In the bivalve floating larva breeding method for raising bivalve floating larvae such as oysters and pearl oysters in the breeding water stored up to the water level at the time of breeding, a plurality of groups are provided so that the breeding aquarium can be selected and used. The normal breeding operation process of one breeding tank that is bred for a predetermined time in the breeding tank, and the breeding water in one breeding tank is increased from the breeding time, and the floating larvae with the increased breeding water A larva transfer operation step for transferring the larvae to the other rearing water tank, a normal rearing operation step for raising the transferred floating larvae in the other rearing water tank, and a means for cleaning the one rearing water tank after the transfer And a cleaning operation step of washing, the in be done automatically after the elapsed time set in advance of each operation step.

  The bivalve floating larva breeding control device according to the present invention is characterized in that in the bivalve floating larva breeding control apparatus for implementing the bivalve floating larva breeding method, a washing water path for supplying washing water to the washing means, and fresh water Floating larvae are transferred between the breeding water supply path, the drainage drainage path for draining the breeding water through the filter, the drainage path for draining the breeding water when washing the breeding tank, and the breeding tank. A larvae transfer path is provided, and a valve is provided in each of the washing water path, the fresh water injection path, the flush drainage path, the discharge path, and the larvae transfer path, and each valve is controlled to open and close.

  In the present invention, floating larvae are transferred from one breeding aquarium to the other breeding aquarium by overflowing the breeding water from the floating larva transport route by utilizing the swimming ability of the floating larvae having high activity. Then, while raising one breeding tank, the floating larva transferred in the other breeding tank is raised. Since each operation process automatically controls the opening and closing of each valve, after transferring the floating larvae that are being bred without restriction of human labor hours to the connected aquarium, the filter and the aquarium are installed with washing water using washing means. It can be cleaned automatically.

  Moreover, as a result of being able to perform unattended work by automatic operation, total water change work, breeding water tank and filter washing, labor saving can be achieved.

  The present invention separates and removes residues such as excrement, moribund shellfish, and residual food at the bottom of the aquarium without mixing them with the floating larvae that are being bred, and can perform washing tank washing automatically, General floating larvae can be raised with high density and high efficiency.

It is the schematic of the state which shows the floating larva breeding apparatus of the bivalve which concerns on one embodiment of this invention, and is breeded with one breeding tank A. It is the schematic of the state which shows the floating larva breeding apparatus of the same bivalve, and transfers floating larva from one breeding tank A to the other breeding tank B. It is a flowchart which shows the process of the normal breeding operation and the larva transfer operation which used the floating larva breeding apparatus of the bivalve. It is a flowchart which shows the process of the washing | cleaning driving | operation using the floating larva breeding apparatus of the same clam. It is a figure which shows the density reduction at the time of larva breeding transfer. It is a figure which shows the time-dependent change of the shell height of a oyster floating larva. It is a figure which shows the comparison with the automatic breeding method using the apparatus of this application, and the conventional still water breeding method.

  Hereinafter, an embodiment of a bivalve floating larva breeding apparatus according to the present invention will be described with reference to the drawings. FIG. 1 and FIG. 2 are schematic views of a bivalve floating larva breeding apparatus, and the bivalve floating larva breeding apparatus shown in FIG. 1 illustrates a pouring apparatus 1 for breeding oyster floating larva as a bivalve. The floating larva breeding apparatus 1 includes a plurality of (two in this embodiment) breeding aquariums A and a breeding aquarium B in which breeding water is stored. Both breeding water tanks A and B have the same shape and are installed at the same height. Then, either is selected and used for raising floating larvae.

  The bottom A1 of one breeding water tank A has an inclined surface that tapers downward (tapered). A breeding water drainage channel (discharge route) 30 provided with a breeding water drainage valve 9 is connected to the bottom of the bottom A1. Thus, by making the bottom part A1 of the breeding water tank A into the inclined surface, the breeding water stored in the breeding water tank A can be easily discharged from the breeding water drainage channel 30.

  An air injection path 31 in which an air injection valve 5 is interposed is connected to the rear side of the breeding water drainage path 30 from the breeding water drainage valve 9. Air is introduced through the air injection path 31 by an air pump (blower) (not shown).

  In the breeding water tank A, for example, a filter 3 having pores of about 0.03 mm is provided. The degree of the filter 3 is set so that the floating larvae to be bred are 0.06 to 0.3 mm, so that the larvae do not enter the filter 3 and that the breeding water can be filtered most effectively. Has been.

  A flush drainage channel (discharge channel) 33 in which a flush drainage valve 4 is interposed is connected to the filter 3. And the breeding water filtered with the filter 3 is the structure discharged | emitted via the drainage channel 33 by pouring with the pump of illustration not shown.

  The other rearing tank B has the same configuration as the rearing tank A. That is, the breeding water drainage channel 35 in which the breeding water drain valve 16 is interposed is connected to the bottom B1 where the inclined surface of the breeding water tank B is formed. In addition, an air injection path 36 in which an air injection valve 13 is interposed is connected to the breeding water drainage path 35.

  In addition, a flush drainage channel 37 in which a flush drainage valve 12 is interposed is connected to the filter 11 provided in the breeding water tank B.

  Between the breeding water drains 30 and 35 of both breeding tanks A and B, a new water injection path (supply path) 38 for supplying fresh water for breeding to the breeding tanks A and B is connected. The connection position of the new water injection path 38 is closer to the rearing tanks A and B than the rearing water drain valves 9 and 16. That is, both ends of the fresh water injection path 38 are connected between the breeding water drain valves 9 and 16 and the connection positions 31a and 36a of the air injection paths 31 and 36. Further, new water injection valves 6 and 14 are provided at both ends of the new water injection path 38, respectively.

  A larvae transfer path 40 is horizontally connected to the upper part (above the filters 3 and 11) of both rearing tanks A and B. At one end of the larva transfer path 40, an opening 40a communicating with the breeding water tank A is formed. Further, an opening 40 b communicating with the breeding water tank B is formed at the other end of the larva transfer route 40. Therefore, the upper parts of the rearing tanks A and B are communicated with each other through the larva transfer route 40.

  Furthermore, a larva transfer path valve 8 is interposed in the middle of the larva transfer path 40, and the larva transfer path 40 can be opened and closed by the larva transfer path valve 8.

  Washing nozzles 7 and 15 as washing means are provided above the filters 3 and 11 in the upper portions of both the rearing tanks A and B, respectively. To each of the cleaning nozzles 7 and 15, a cleaning water passage 39 having cleaning water passage valves 10 and 17 interposed is connected. And it is comprised so that the washing water supplied via this washing water channel | path 39 may be injected in breeding water tank A, B from each washing nozzle 7,15. A cleaning nozzle that does not have an on-off valve can also be used.

  The valves 4, 5, 6, 8, 9, 12, 13, 14, 16, and 17 connected to the respective paths employ electromagnetic valves, and are controlled to be opened and closed by a control device (not shown). Yes.

The floating larva breeding apparatus 1 according to the present embodiment is configured as described above. Next, an oyster floating larva breeding method using the floating larva breeding apparatus 1 will be described with reference to the flowcharts of FIGS. 3 and 4. To do. This floating larva breeding method exemplifies the case of using the other breeding tank B after using one breeding tank A first.
(Normal rearing operation of rearing tank A)
First, the normal driving situation when the breeding aquarium A is used will be described with reference to FIG. The breeding water level (breding water level) L during breeding is set at a position higher than the filter 3 and lower than the opening 40a of the larvae transfer path 40, as shown in FIG.

  First, the opening / closing valve of the washing nozzle 7 on the breeding water tank A side, the larva transfer path valve 8, the breeding water drain valve 9 and the washing water path valve 10 are closed (S2). Further, the flush drain valve 4, the air injection valve 5 and the fresh water injection valve 6 are opened sequentially (S3 to S5). By opening the new water injection valve 6, new water is supplied from below into the breeding aquarium A through the new water injection path 38 and the breeding water drainage path 30. Oyster floating larvae are bred in a state where the breeding water in the breeding aquarium A maintains the water level L during breeding (S6).

  Further, since the air injection valve 5 is opened, air is introduced into the breeding water tank A from the bottom via the air injection path 31. The air introduced into the breeding aquarium A becomes fine bubbles and raises the breeding water. The floating larvae of the oysters in the rearing tank A have floating properties, so they tend to rise with fine bubbles, and the upper part of the rearing water (above the filter 3) and then the whole rearing water float. Become.

  The breeding water is filtered through the filter 3 and then drained through the flush drainage channel 33. The activated floating larvae are sufficiently larger than the mesh of the filter 3 and float on the side of the filter 3 so that they do not pass through the filter 3 or cause clogging.

Thus, the floating larvae are bred in the breeding aquarium A for a predetermined time. The breeding time in the breeding aquarium A is set in advance and is managed by the computer of the facility. When the floating larvae are bred in the breeding aquarium A for a predetermined time, the floating larvae are transferred to the aquarium B that is not in use, and the breeding breeding with the aquarium B is started (S8). That is, the start timing of the pouring breeding by the water tank B is appropriately determined according to the breeding elapsed time in the breeding water tank A, and the end timing ends after the transfer of a predetermined fixed amount of water.
(Larvae transfer operation from rearing tank A to rearing tank B)
Next, the floating larva transfer operation from the rearing tank A to the rearing tank B will be described. The opening / closing valve of the washing nozzle 15 on the breeding water tank B side, the breeding water drain valve 16 and the washing water path valve 17 are closed (S9). Further, the flush drain valve 12, the air injection valve 13, and the fresh water injection valve 14 are sequentially opened (S9 to S12).

  When the water level in the rearing tank B becomes the rearing water level L (S13), the larvae transfer path valve 8 is opened (S14), and the drainage drain valve 4 and the air injection valve 5 of the rearing tank A are closed ( S15 and S16).

  Thus, by closing the flush drain valve 4 and the air injection valve 5, the amount of breeding water supplied into the breeding aquarium A increases, and reaches the water level H at the time of transfer reaching the larvae transfer path 40 (FIG. 2). reference). As a result, the breeding water in the breeding aquarium A overflows the breeding aquarium A, flows through the larva transfer route 40, and flows into the breeding tank B. Taking advantage of the floating nature of the floating larvae having high activity, for example, by supplying water of 0.5 l / min or more from the fresh water injection path 38, the floating larvae in the breeding aquarium A together with the breeding water also pass through the larva transport route 40. It is transferred to breeding tank B together.

After a predetermined time has passed, the transfer of the floating larvae is completed (S17), the drainage drain valve 4 of the breeding water tank A is opened, and the fresh water injection valve 6 and the larvae transfer path valve 8 are closed (S18 and S19). After completion of the transfer operation, the pouring breeding operation in the breeding tank B (normal breeding operation of the breeding tank B) is started in the same manner as the breeding tank A (S1A).
(Cleaning operation of rearing tank A)
Next, the washing operation of the rearing tank A will be described with reference to FIG. After the larvae transfer, the washing operation of the rearing tank A is started (S20).

  The breeding water drain valve 9 is opened, and the breeding water stored in the breeding water tank A is discharged (S21). Further, the opening / closing valve of the cleaning nozzle 7 and the cleaning water passage valve 10 are opened, and clean water as cleaning water is sprayed downward from the cleaning nozzle 7. The washing water sprayed from the washing nozzle 7 removes excreta adhering to the filter 3 and residues such as residual food and moribund shellfish deposited on the bottom of the breeding water tank A (S22). In addition, tap water and seawater are used as washing water. Moreover, a sodium hypochlorite solution is mixed as appropriate.

  After a predetermined time has passed, the drainage drain valve 4 and the breeding water drain valve 9 are closed, and the reservoir is washed with the washing water stored in the breeding water tank A (S23 to S24). Further, the opening / closing valve of the cleaning nozzle 7 and the cleaning water passage valve 10 are closed, the flushing drain valve 4 and the breeding water drain valve 9 are opened, and the storage cleaning water is discharged (S25). Since the bottom A1 of the breeding aquarium A is inclined so as to taper downward, the filter 3 washed with the washing water and the residue of the breeding aquarium A such as dirt and moribund can be smoothly removed together with the washing water. Can be discharged reliably.

  After the reservoir cleaning water is discharged, the opening / closing valve of the cleaning nozzle 7 and the cleaning water passage valve 10 are opened, and the breeding water tank A and the filter 3 are rinsed with the cleaning water (S26).

  Further, the drainage drain valve 4 and the breeding water drain valve 9 are closed (S27), and when the washing water is increased and the washing water level reaches a predetermined position (water level H at the time of transfer), the on-off valve of the washing nozzle 7 and the washing water. The path valve 10 is closed, and the injection of washing water from the nozzle 7 is stopped (S28). Note that the washing water does not flow from the larva transfer path 40 to the breeding aquarium B because the larva transfer path valve 8 is closed.

  Further, the drainage drain valve 4 and the breeding water drain valve 9 are opened, and the rinse washing water is drained (S29). After draining is completed, the drainage drain valve 4 and the breeding water drain valve 9 are closed, and the cleaning process is terminated (S30 and S31).

  In addition, also in the breeding breeding of the breeding water tank B, the same transfer process and washing process are performed after a predetermined time has elapsed.

  As described above, the opening and closing of each valve 4, 5, 6, 8, 9, 12, 13, 14, 16, 17 is automatically controlled using the floating larva transfer technology. Without limitation, the rearing tanks A and B and the filters 3 and 11 can be washed at any time for 24 hours.

That is, after being transferred to the breeding tanks A and B to which the floating larvae being bred are connected, the filters 3 and 11 and the breeding tanks A and B are washed with washing water and sodium hypochlorite solution using the washing nozzles 7 and 15.
+ B can be sterilized and washed automatically. Moreover, as a result of the unmanned operation of the automatic water exchange operation and the cleaning of the rearing water tanks A and B and the filters 3 and 11, automatic labor saving can be achieved.

  For the purpose of improving the survival rate of oyster floating larva breeding among bivalves, the breeding effect using the floating larva breeding apparatus according to the present invention was examined.

  The breeding experiment was conducted twice between July 31 and September 14, 2008. The breeding density at the start of the experiment was 168 to 268, and the feeds used were two brand names of Yanmar concentrated quilt Ch. Calcitrans and Ch. Gracilis (Yanmar Corporation). The water temperature was a constant temperature of 28.0 to 29.0 ° C., and breeding water was flowed in an amount of 0.5 to 1.8 L per minute of microfiltered seawater treated with hollow core membrane (UF). As for the amount of feed, 0.05 to 130,000,000 cells per day were continuously fed with a peristaltic pump in terms of Ch.

  In the automatic water exchange using the transfer route according to the present invention, the transfer situation of 10 times in total (floating amount at transfer of 3.5 L / min) was investigated using floating larvae having an average shell height of 67 to 230 μm. The result is shown in FIG. In the figure, the vertical axis represents the density of floating larvae, and the horizontal axis represents the transfer time.

  Specifically, in the first experiment, six floating larvae at a shell height (Sh) of 92 μm, Sh136 μm, Sh154 μm, Sh176 μm, Sh198 μm and Sh230 μm were sampled. Also. In the second breeding experiment, four cases of floating larvae at the time of Sh67 μm, Sh73 μm, Sh91 μm and Sh9 4 μm were sampled.

  As shown in FIG. 5, it was confirmed that 99.9% of floating larvae were transferred to another water tank in 10 cases after 120 minutes had passed since the start of automatic water exchange.

  The effect of the present invention will be verified using a conventional water-stop breeding method that is generally implemented as a comparative example. FIG. 6 shows the experimental results of changes over time in the shell height of floating larvae. In the figure, the vertical axis indicates the shell height of floating larvae, and the horizontal axis indicates time. In addition, FIG. 7 shows a comparison of the daily growth of floating larvae, the yield of mature larvae, and the rearing density.

  Compared with the breeding method using the floating larvae breeding apparatus according to the present invention and the conventional still water breeding method, there was no significant difference in the change in the shell height of floating larvae and the daily growth amount, and normal growth was confirmed (FIG. 6). And FIG. 7). In addition, the mature larvae yield, which is the ratio of the number of individuals housed at the start of breeding and the number of mature larvae recovered by rearing after breeding, tends to be higher than that of the conventional method. Improvement was confirmed (see FIG. 7). The breeding density immediately before selection was several tens of times that of the conventional method, and overwhelming high-density breeding was possible (see FIG. 7).

  The number of mature larvae produced in two rearing experiments using this device is 403.8 million for the first time and 603.33 for the second time. When producing mature larvae of the amount produced by the breeding method using this device by the conventional method, if the breeding density of mature larvae of the conventional method is 1 piece / ml, the amount of breeding water will be 4 to 6t, and 1t panlite 4-6 water tanks are required, and at least 3-4 workers are required. The work in this breeding experiment was carried out by one person, and we were able to breed with automatic driving except for the feeding setting.

  As is clear from the above experimental results, in each growth stage of the floating larvae (arbitrary shell height), the entire floating larvae can be transferred to another aquarium within a predetermined time, and Can be grown. As a result, the breeding aquarium and filter can be washed at any time for 24 hours without any limitation on human labor hours, and automatic operation is possible.

  In addition, since the yield of mature larvae and overwhelming high-density breeding are possible, floating larvae can be bred with high density and high efficiency.

  The present invention enables high stability and productivity of bivalve artificial seedling production, saves labor by automation, saves space by high density, and realizes production cost reduction on land by industrial production It is. In recent years, coastal bivalve resources in Japan have decreased significantly, but it greatly contributes to the aquaculture business for the recovery of bivalve resources.

A Breeding tank B Breeding tank 3 Filter 4 Overflow drain valve 5 Air injection valve 6 Fresh water injection valve 7 Cleaning nozzle (cleaning means)
8 Larval Transfer Path Valve 9 Breeding Water Drain Valve 10 Washing Water Path Valve 11 Filter 12 Draining Drain Valve 13 Air Injection Valve 14 Fresh Water Injection Valve 16 Breeding Water Drain Valve 17 Washing Water Path Valve 30 Breeding Water Drainage Path 31 Air Injection Path 33 Drainage channel (drainage channel)
35 Breeding water drainage channel 36 Air injection channel 37 Drainage drainage channel (drainage channel)
38 New water injection route (supply route)
39 Washing water route 40 Larval transfer route L Water level during rearing H Water level during transfer

Claims (2)

A bivalve that feeds fresh water to a breeding aquarium where breeding water is stored, drains the breeding water through a filter, and breeds floating larvae of bivalves such as oysters and pearl oysters in the breeding water stored up to the breeding water level In the floating larva breeding method of
A plurality of units are provided so that the breeding tank can be selected and used, and the normal breeding operation process of one breeding tank that is raised in one breeding tank for a predetermined period of time and the breeding water of the one breeding tank are more A larva transfer operation step of transferring the floating larvae together with the increased breeding water to the other breeding tank via the larva transfer route, and a normal breeding operation step of breeding the transferred floating larvae in the other breeding tank, A method for raising bivalve floating larvae, comprising: a washing operation step of washing one breeding water tank after the transfer with a washing means, wherein each of the operation steps is automatically performed after a preset time.   In the bivalve floating larva breeding control apparatus for carrying out the bivalve floating larva breeding method according to claim 1, a washing water path for supplying washing water to the washing means, a new water injection path for supplying fresh water, A drainage drainage channel for draining the breeding water through the filter, a drainage route for draining the breeding water when washing the breeding aquarium, and a larva transport route for transferring floating larvae between the breeding aquariums are provided, The bivalve floating larvae breeding control apparatus, wherein valves are provided in the washing water path, the fresh water injection path, the flush drainage path, the discharge path, and the larvae transfer path, respectively, and each valve is controlled to open and close.

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