JP7207377B2 - Water flow shield for feeding in aquaculture tank, and feeding method in aquaculture tank - Google Patents

Description

TECHNICAL FIELD The present invention relates to a water flow shield for use in feeding juvenile fish or shrimp in an aquaculture tank and a method for feeding juvenile fish or juvenile shrimp in an aquaculture tank.

While the world's demand for marine products is increasing, the world's marine fisheries production has peaked, and the expansion of the demand for marine products needs to be supported by the aquaculture industry. Since there is a limit to the expansion of marine aquaculture due to restrictions on areas suitable for aquaculture, expectations are rising for land-based aquaculture that can achieve higher productivity than marine aquaculture regardless of location (for example, Non-Patent Document 1. See page 2 of

Land-based aquaculture currently faces the biggest bottleneck of high initial costs and high running costs, but feed costs are also increasing (see page 3 of Non-Patent Document 1).

Fish and shellfish to be farmed are bred from juvenile fish or juvenile shrimp, so it is necessary to efficiently feed the juvenile fish or juvenile shrimp.

There is a device that automatically feeds juvenile fish cultured in a water tank (see, for example, Patent Document 1). The automatic feeding device for juvenile fish of Patent Document 1 has a feeding machine 1, a mixer 2, a water pipe 3, and a feeding controller 4, and under the control of the feeding controller 4, the feeding operation to juvenile fish in the culture tank is performed for a predetermined time. automatically executed each time.

In land-based aquaculture, in order to prevent foreign substances such as excreta and cast-off shells of the fish and shellfish to be cultivated and leftover food from accumulating at the bottom of the aquaculture tank, and to promote the growth of the fish and shellfish, Water is caused to flow (see, for example, Patent Document 2).

JP-A-5-15277 Japanese Patent Application Laid-Open No. 2003-235391

"About land-based aquaculture", [online], Fisheries Agency, June 2013, [searched on June 8, 2020], Internet <URL: https://www.jfa.maff.go.jp/j/ saibai/yousyoku/arikata/pdf/4-3-1docu.pdf>

As described above, in land-based aquaculture, there is a water flow in the water tank, so juvenile fish or shrimp that are small in size and have low swimming ability cannot move freely in the water tank.

The bait for juvenile fish or juvenile shrimp is in the form of powder, and when placed in a tank, it spreads and moves along with the water current. Therefore, it is not possible to efficiently feed juvenile fish or juvenile shrimp that have low swimming ability as described above. Adding a large amount of food to the tank increases feed costs and contaminates the water in the tank with diffused food. Such problems are the same in both manual feeding and automatic feeding as in Patent Document 1.

The present invention provides a water flow shield for use in feeding juvenile fish or shrimp in an aquaculture tank, and a method for feeding juvenile or juvenile shrimp in an aquaculture tank that can be fed efficiently. for the purpose.

The inventors of the present application observed the behavior of juvenile fish or juvenile shrimp when feeding juvenile fish or juvenile shrimp in an aquaculture tank with water flow, and studied a method for efficient feeding. With the idea of blocking the water flow during feeding, the present invention was completed through experiments and trial production. The gist of the present invention is as follows.

[1]
In land-based aquaculture, it is used when feeding juvenile fish or juvenile shrimp cultivated in a water tank with water flow,
sinks to the bottom of the water tank and stands on its own;
Located upstream of the water flow with respect to the vessel containing the fry or shrimp fry, shielding the vessel from the water flow;
Water flow shield for feeding in aquaculture tanks.

[2]
substantially U-shaped, substantially semicircular, substantially arc-shaped, or substantially V-shaped in plan view,
The water flow shield for feeding in aquaculture tanks according to [1].

[3]
is ceramic,
[1] or 2. The water flow shield for feeding in an aquaculture tank.

[4]
An engaging member that can be engaged with a hook-shaped member or a gripping member that can be gripped is provided,
A water flow shield for feeding in an aquaculture tank according to any one of [1] to [3].

[5]
A step of arranging the water flow shield for feeding in an aquaculture tank according to any one of [1] to [4] on the bottom of a water tank in which there is a water flow in land-based aquaculture;
Placing a vessel containing juvenile fish or juvenile shrimp food on the bottom of the water downstream of the water flow shield;
including,
Feeding method in aquaculture tank.

According to the water flow shield for feeding in aquaculture tanks and the feeding method in aquaculture tanks of the present invention, the water flow shield is used when feeding juvenile fish or juvenile shrimp cultivated in an aquarium with water flow in land aquaculture. It sinks to the bottom of the water tank and stands on its own, and is positioned upstream of the water flow with respect to the vessel containing the food for the juvenile fish or the juvenile shrimp, shielding the vessel from the water flow.

As a result, the juvenile fish or juvenile shrimp that are small in size and have low swimming ability are not washed away by the water flow, and the juvenile fish or juvenile shrimp can gather in the vessel and eat the bait. Therefore, the amount of wasted food is extremely reduced, so that the cost of feed can be reduced, and contamination of the water in the tank by the diffused food can be suppressed.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic plan view showing an example of an aquaculture tank having a circular shape in plan view, in which a feeding water flow shield according to an embodiment of the present invention is arranged; Fig. 3 is a perspective view of the water flow shield shown with a vessel containing fry or shrimp food; FIG. 10 is a schematic plan view showing the device and the water flow shield, in which (a) shows an example in which the device is arranged slightly apart from the water flow shield, and (b) shows the device placed closer to the water flow than in (a). An example of close proximity to a shield is shown. It is a schematic plan view showing a modification of the vessel and the water flow shield, (a) is an example in which the vessel is arranged slightly apart from the water flow shield, (b) is a is brought close to the water flow shield. Fig. 10 is a perspective view showing an example of a water flow shield for feeding provided with an engaging member;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments according to the present invention will be described with reference to the drawings.

<Aquaculture layer>
The aquaculture tank A in which the feeding water flow shield 1 according to the embodiment of the present invention is arranged has, for example, a circular shape in plan view as shown in the schematic plan view of FIG. It may be rectangular, or may be of any other shape.

The fish and shellfish to be cultured in the water tank A is, for example, kuruma prawns, which are reared from juvenile prawns. Juvenile shrimp is about 1 mm to 5 mm in size. Since prawns have a habit of burrowing into sand, there is a sand bed S in the water tank A and water W thereon. If the fish and shellfish cultured in the water tank A do not have the habit of burrowing in sand, the sand bed S may be eliminated.

A water flow F is generated in the water W in the water tank A by a water flow generator G. The water flow generator G generates a water flow F by supplying water, air, or the like into the water tank A, for example. The water flow F is generated not only to prevent foreign matters such as excrement, cast-off shells, and leftover food of the fish and shellfish to be cultivated from accumulating on the bottom of the water, but also to promote the growth of the fish and shellfish to be cultivated.

In FIG. 1, when feeding juvenile shrimp in a water tank A, a feeding water flow shield 1 and a vessel 2, for example a plate, containing food 3 for juvenile shrimp are placed in water W and the bottom of the water. It shows a state in which it is placed in Vessel 2 has a density greater than 1 for placement on the bottom of the water. The vessel 2 is, for example, ceramic, but may also be metal or synthetic resin having a density greater than one.

Since the food 3 for young shrimp is powdery, before putting the container 2 into the water W, the powdery food 3 is soaked in water and placed on the container 2.例文帳に追加As a result, when the dish 2 containing the food 3 is put in the water W and arranged on the bottom of the water, the food 3 does not spread.

<Water flow shield for feeding>
As shown in the schematic plan view of FIG. 1, the perspective view of FIG. 2, and the schematic plan views of FIGS. It sinks to the bottom of the water and stands on its own. The density of the water flow shield 1 is preferably about 1.5 to 3 in consideration of the ability to stand on its own stably in the water tank A and the operability when arranging or moving it. As the water flow shield 1, it is preferable to use ceramics that have an appropriate density of, for example, about 1.8 to 2.3, have good operability, do not look strange in the water tank A, and do not corrode. However, it may be a metal or synthetic resin having a density within the above range.

A water flow shield 1 is positioned upstream of a water flow F with respect to a vessel 2 containing juvenile shrimp feed 3, and shields the vessel 2 from the water flow F. When the water flow shield 1 is placed in the water tank A, as shown in the schematic plan views of FIGS. The central portion C of the shield 1 has a shape that protrudes toward the water flow F from both ends D and E of the water flow shield 1 . As a result, the drag coefficient to the water flow F can be reduced, so the resistance to the water flow F is reduced.

<Modification>
As shown in the schematic plan views of FIGS. 4(a) and 4(b), the planar shape of the portion of the water flow shield 1 facing the water flow F is formed into a mountain shape, which is also the "substantially U shape in plan view" in the present invention. Included in the water flow shield 1. Alternatively, it may be substantially semicircular, substantially arc-shaped, or substantially V-shaped instead of substantially U-shaped. The term “substantially V-shaped” includes cases where two sides forming a V-shape in a plan view have an obtuse crossing angle.

As shown in the perspective view of FIG. 5, it is a more preferable embodiment to provide the water flow shield 1 for feeding with an engaging member 4 . The engaging member 4 protrudes upward from, for example, the upper surface 1A of the feeding water flow shield 1, and can be engaged with a hook-shaped member (not shown). In a state in which the hook-like member attached to the tip of the rod or the like is engaged with the engaging member 4, the feeding water flow shield 1 can be easily arranged at an appropriate position in the water tank A and moved.

A gripping member that can be gripped may be provided instead of the engaging member 4 projecting upward. As a result, the water flow shield 1 for feeding can be placed at an appropriate position in the water tank A or moved while holding the holding member.

In the description of the above embodiment, an example of breeding juvenile shrimp in water tank A was shown, but juvenile shrimp may be reared in water tank A. In that case, feed 3 for juvenile fish is placed in the vessel 2.

<Feeding method in aquaculture tank>
The method for feeding in aquaculture tank A according to the embodiment of the present invention includes a first step of placing a feeding water flow shield 1 on the bottom of a water tank A where there is a water flow F in land aquaculture; a second step of placing a vessel 2 containing 3 on the bottom of the water at a position where the water flow F is blocked by the water flow shield 1;

Since the bait 3 for fry or juvenile shrimp is powdery, a step of soaking the powdery bait 3 in water and placing it on the container 2 is carried out before performing the second step. As a result, when the dish 2 containing the food 3 is put in the water W and placed on the bottom of the water in the second step, the food 3 does not spread.

<Effect>
According to the water flow shield 1 for feeding in the aquaculture tank A and the feeding method in the aquaculture tank A according to the embodiment of the present invention, the water flow shield 1 can It is used when feeding fry or shrimp to be cultivated, sinks to the bottom of the water tank A and stands on its own, is located upstream of the water flow F with respect to the vessel 2 containing the feed 3 for the fry or shrimp, 2 from the water flow F.

As a result, the fry or shrimp that are small in size and have a low swimming ability are not washed away by the water flow F, and the fry or shrimp can gather in the container 2 and eat the bait 3.例文帳に追加Therefore, the amount of wasted food 3 is greatly reduced, so that the feed cost can be reduced and the contamination of the water W in the water tank A by the diffused food 3 can be suppressed.

When actually using the feeding water flow shield 1 having the shape shown in FIGS. did it. It was also confirmed that the bait 3 did not spread in the water tank A and did not contaminate the water W in the water tank A.

All of the descriptions of the above embodiments are examples, and the present invention is not limited to these. Various modifications and changes may be made without departing from the scope of the invention.

1 Feeding water flow shield 1A Upper surface 2 Vessel 3 Bait 4 Engagement member A Water tank B Horizontal direction C perpendicular to water flow Central parts D, E Edges F Water flow G Water flow generator S Sand bed W Water

Claims (5)

In land-based aquaculture, it is used when feeding juvenile fish or juvenile shrimp cultivated in a water tank with water flow,
sinks to the bottom of the water tank and stands on its own;
located upstream of the water flow with respect to the vessel containing the fry or shrimp fry, shielding the vessel from the water flow;
Water flow shield for feeding in aquaculture tanks. substantially U-shaped, substantially semicircular, substantially arc-shaped, or substantially V-shaped in plan view,
The water flow shield for feeding in an aquaculture tank according to claim 1. is ceramic,
The water flow shield for feeding in aquaculture tanks according to claim 1 or 2. An engaging member that can be engaged with a hook-shaped member or a gripping member that can be gripped is provided,
A water flow shield for feeding in an aquaculture tank according to any one of claims 1 to 3. A step of arranging the water flow shield for feeding in an aquaculture tank according to any one of claims 1 to 4 on the bottom of a water tank in which there is a water flow in land-based aquaculture;
A step of placing a vessel containing food for juvenile fish or juvenile shrimp on the bottom of the water at a position where the water flow is blocked by the water flow shield;
including,
Feeding method in aquaculture tank.

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