JP7354383B2 - Cephalopod feeding method and cephalopod feeding equipment - Google Patents

Description

The present invention relates to a method for feeding cephalopods and a feeding device for cephalopods.

Squid, octopus, and other cephalopods are very familiar to the Japanese diet, but farming techniques for them have not yet been established. In connection with this aquaculture technique, the feed is important. For example, Patent Document 1 discloses feed for culturing cephalopods. Furthermore, it has been pointed out that it is difficult to raise octopuses in their floating larval stage, as described in Non-Patent Document 1.

Japanese Patent Application Publication No. 2001-275581 JP 2017-6054 Publication

Nobuhiko Akiyama (Faculty of Oceanography, Tokai University), “Current status of high-density housing technology and larval rearing of octopus”, 1st lecture of Fisheries Society Fisheries Breeding Conference 2017, collection of abstracts pp7-8, 2017

In the aquaculture of aquatic organisms, many of the aquatic organisms to be cultivated are fish, and the fish feed while swimming in the water. For this reason, they have been fed with raw food or pelleted food manually or mechanically. This feeding method is suitable for their ecology, as they can continue swimming while feeding.

On the other hand, when feeding cephalopods, conventionally, feeding has been carried out using the same method as feeding these fishes. Also in the above-mentioned Patent Document 1, feeding by spraying is considered so that the sedimentation rate is specified. However, with regard to cephalopods, feeding methods for fish are simply applied to cephalopods, and appropriate feeding methods and feeding equipment have not been studied so far. An object of the present invention is to provide a feeding method and feeding device suitable for cephalopods.

As a result of extensive research in order to solve the above-mentioned problems, the present inventors found that the following invention met the above-mentioned objects, leading to the present invention.

(1) A method for feeding an octopus , which includes the steps of: holding the bait in water using an underwater holding means that holds the bait in the water of an aquaculture tank; and feeding the octopus with the bait. Method.
(2) The feeding method according to (1), wherein the step of holding the bait underwater by the underwater holding means includes the step of shaking the bait underwater.
(3) The step of holding the bait in water by the underwater holding means includes the step of suspending the bait by a hanging holding means for suspending and holding the bait in the water from the opening of the aquaculture tank (1). ) or the feeding method described in (2).
(4) The feeding method according to (3) above, wherein the hanging holding means includes a string-like body or a rod-like body to which the bait is attached.
( 5 ) The step of holding the bait underwater by the underwater holding means includes the step of holding the bait by a support holding means for attaching the bait to a support disposed in the culture tank and holding it underwater. , the feeding method according to (1) or (2) above.
( 6 ) The feeding method according to ( 5 ) above, wherein the supporting and holding means includes a string-like body or a rod-like body suspended within the culture tank.
( 7 ) The feeding method according to ( 5 ) above, wherein the supporting and holding means includes a rod-shaped body disposed within the culture tank.
( 8 ) The feeding method according to (4) or (6 ) above, wherein the string-like body is at least one string-like body selected from the group consisting of fishing line, kite line, sewing thread, and wire.
( 9 ) Any one of (4), (6), or (7) above, wherein the rod-shaped body is at least one rod-shaped body selected from the group consisting of a cylindrical body, a columnar body, and a cone-shaped body. Feeding method described in.
( 10 ) The feeding method according to any one of (1) to ( 9 ) above, wherein the bait is separated from the bottom of the culture tank.
(11) A method for cultivating octopuses, which comprises applying the feeding method according to any one of (1) to (10) above to cultivating octopuses at least in the floating larval stage.

( 12 ) An apparatus for feeding an octopus, which is equipped with an underwater bait holding means that holds the bait in the water of the aquaculture tank at a distance from the bottom of the aquaculture tank. An octopus feeding device that is a support holding means that is attached to a support that is a rod-shaped body that is attached to the side and held underwater .
( 13 ) The octopus feeding device according to ( 12 ) , further comprising a swinging means for swinging the bait held in the underwater holding means.

According to the feeding method and feeding device of the present invention, cephalopods are efficiently fed.

FIG. 1 is a schematic diagram of a feeding device according to a first embodiment of the present invention. FIG. 3 is a schematic diagram of a feeding device according to a second embodiment of the present invention. FIG. 3 is a schematic diagram of a feeding device according to a third embodiment of the present invention.

The present invention will be described in detail below with reference to examples, but the present invention is not limited to the following examples, and can be implemented with arbitrary changes without departing from the gist of the invention. . Note that in this specification, "A to B" or "A to B" is used as an expression including numerical values or physical quantities before and after it. Furthermore, in this specification, the expression "A and/or B" means "one or both of A and B." That is, "A and/or B" includes "A only", "B only", and "both A and B".

The present invention is a method for feeding cephalopods, which includes the steps of: retaining bait in water using an underwater retaining means that retains the bait in water of a culture tank; and making the cephalopod feed the bait. Concerning methods of feeding cephalopods, including: The present invention also relates to a feeding device for cephalopods having an underwater holding means for holding food in the water of a culture tank. The feeding method of the present invention can be carried out using the feeding device of the present invention.

[Underwater retention means]
The "underwater retention means" of the present invention is means for retaining food for cephalopods in water between the water surface and the bottom of the culture tank. As this underwater holding means, various methods that can hold the bait underwater can be used. As the underwater holding means, for example, a hanging holding means or a supporting holding means, which will be described later, can be used. This underwater holding means is used to hold the bait in the water of the aquaculture tank of the feeding method of the present invention.The underwater holding means holds the bait in the water, and the cephalopod is fed with the bait. .

In feeding cephalopods according to the present invention, food for the cephalopods is held in water in a culture tank by an underwater holding means and then fed. The present inventors have discovered that by performing such feeding, the feeding of cephalopods is unexpectedly good. By performing this feeding, it is possible to feed the cephalopods that are swimming in the aquarium. As a result, the amount of food consumed also increases because the feeding time increases. Also, depending on the type of cephalopod, it becomes easy to visually confirm an increase in food intake.

Furthermore, by attaching bait to the underwater holding means, it is clear that the bait is present at the attached location, making it easy to grasp the amount of remaining bait. Furthermore, since each individual cephalopod can feed at any time the food attached to the underwater holding means, the number of feeding operations can be easily adjusted. Further, remaining bait can be easily recovered by recovering the underwater holding means to which the bait is attached. Therefore, it is possible to prevent food that is not consumed by the cephalopods from accumulating at the bottom of the culture tank and contaminating the culture environment. In particular, it has been observed that cephalopods tend not to feed on food that has landed on the bottom of the culture tank, so the present invention is also effective from the viewpoint of feeding efficiency.

In the present invention, the underwater holding means can have a structure in which bait is attached to a string-like body or a rod-like body. For example, the bait can be fixed by tying the bait to a string-shaped body or a rod-shaped body, or by providing a hole in the bait and passing it through it. For this string-like body, various fibrous bodies such as fishing line, kite line, sewing thread, wire, etc. can be used alone or in appropriate combinations. Further, as the rod-shaped body, a cylindrical body, a columnar body, a cone-shaped body, etc. can be used alone or in an appropriate combination. In order for the cephalopod to easily come into contact with the bait without being hindered by the underwater holding means, it is preferable that the area around the bait attachment position of the underwater holding means be thin. In the case of a rod-shaped body, the entire rod-shaped body may be thin, or only the mounting position may be thin. Furthermore, the present invention relates to feeding cephalopods, and since the feed surrounding portion of the underwater holding means is used while submerged in salt water in the aquaculture tank, it is not possible to form it from a water-resistant or salt-resistant material. preferable. For example, resin, wood, metal, carbon fiber, glass fiber, etc. can be used as these materials.

[Suspension holding means]
The underwater holding means of the present invention includes hanging holding means. This "suspension holding means" is a means for holding the bait attached and suspended in water from the opening of the culture tank. As the hanging holding means, for example, a string-like body or a rod-like body to which bait is attached can be used as is. It is also possible to use a device equipped with a fixture for fixing a string-like body or a rod-like body to which bait is attached. In the feeding method of the present invention, the step of holding the bait in water can include the step of suspending the bait from the opening of the culture tank using a suspension holding means for suspending and holding the bait in the water.

The suspension holding means of the present invention includes a string-shaped body or a rod-shaped body to which bait is attached, and is configured to suspend the string-shaped body or rod-shaped body to which the bait is attached directly into the water from the opening of the aquaculture tank. Can be done. By using such a string-like body or a rod-like body, it is possible to arrange and collect bait from the opening side with a simple operation. This string-like body or rod-like body can be hung by holding the end thereof by hand, or can be arranged so as to hang from the edge of the opening.

The suspension holding means of the present invention includes a fixture for fixing a hanging part of a string-shaped body or a rod-shaped body to which bait is attached, and has a configuration in which the bait is suspended in water of an aquaculture tank by suspending the hanging part in water. It can be done. The fixture in the present invention is for fixing the hanging part of a string-like body or a rod-like body to which bait is attached. By fixing the hanging portion to this fixture, it is possible to easily place, move, and retrieve the bait into the water using the hanging holding means by handling the fixture. This fixture may be, for example, rod-shaped, rod-shaped, plate-shaped, or the like. These fixtures can be configured such that a part of them is placed outside the aquaculture tank or near the lid, and the part with the hanging part attached is placed in the opening at the top of the aquaculture tank, or the part with the hanging part attached is placed in the opening at the top of the aquaculture tank. It is possible to have a bridge configuration.

[Supporting and holding means]
Other examples of underwater holding means include support holding means. This "supporting and holding means" is a means for attaching bait to a support placed on the side or bottom of the culture tank and holding it in water. This supporting and holding means can be, for example, a string-like body or a rod-like body suspended within the culture tank. Alternatively, it can be a rod-shaped body placed in a culture tank. The feeding method of the present invention can include the step of holding the bait in water by attaching the bait to a support disposed in a culture tank and holding it by a support holding means for holding the bait in the water.

The support and holding means may be, for example, a string-like body or a rod-like body suspended within the culture tank. Bait can be attached to this string-shaped body or rod-shaped body to support the bait so that it is held underwater. By feeding in this way, cephalopods can feed efficiently. This string-shaped body or rod-shaped body can be arranged so as to bridge between the sides of the culture tank or between the bottom and the sides. Attachment portions can be provided on the sides and bottom of the culture tank to facilitate attachment of string-like bodies and rod-like bodies. Further, an attachment part may be provided on the string-like body or the rod-like body side so that it can be easily attached to the side surface or bottom of the culture tank. The attachment portion is a member for attaching a string-like body or a rod-like body. The attachment portion can be shaped like a claw, a ring, a pinch, a screw, a plug, a suction cup, or the like. Using these attachment parts, a string-like body or a rod-like body can be spanned within the culture tank.

As the support and holding means, a rod-shaped body or the like placed in the culture tank can be used, and bait can be attached to the rod-shaped body and supported so as to be held underwater. By feeding in this way, cephalopods can feed efficiently. This rod-shaped body can be provided at the bottom or side of the culture tank. The rod-like body can maintain its shape even when bait is attached to the tip or middle part. Therefore, bait can be held underwater by attaching at least one part of the rod to the bottom or side. In order to provide the rod-shaped body on the bottom or side surface, a mounting part such as that used for the above-mentioned bridge may be provided on the side surface or bottom of the culture tank or on the rod-shaped body.

[Aquaculture tank]
In the present invention, the term "culture tank" refers to equipment that can store a certain amount of water that can be used to raise cephalopods. This aquaculture tank includes equipment for cultivating cephalopods, as well as for raising, transporting, and acclimatizing them. When raising cephalopods in the culture tank, it is preferable to continuously measure the pH, dissolved oxygen amount, ammonia concentration, etc., and keep them within appropriate ranges. The aquaculture tank may utilize part of the ocean, rivers, lakes, or marshes, or may include artificial aquaculture equipment. In particular, in the present invention, artificial terrestrial facilities that allow easy management of aquaculture tanks are preferred.

[Separation from the bottom]
In feeding cephalopods according to the present invention, it is preferable that the bait held by the underwater holding means be separated from the bottom of the culture tank. The distance from the bottom can be 1 cm or more, 5 cm or more, 10 cm or more, 15 cm or more, 20 cm or more, 25 cm or more, 30 cm or more, 35 cm or more, or 40 cm or more in the water surface direction. It is preferable for cephalopods to be separated from the bottom in this way, since it is difficult for the cephalopods to feed on food that has settled down and is in contact with the bottom.

[Separation from water surface]
Further, the distance from the water surface is not particularly limited, and it may be floating on the water surface or may be separated from the water surface. The distance from the water surface can be 1 cm or more, 5 cm or more, 10 cm or more, 15 cm or more, 20 cm or more, 25 cm or more, 30 cm or more, 35 cm or more, or 40 cm or more in the depth direction. Although the bait may be located on the water surface, it is preferable that the bait be located away from the water surface because the cephalopods inside the culture tank can feed without having to rise near the water surface.

[Swinging of bait]
Further, in the feeding method of the present invention, it is preferable that the bait held by the underwater holding means is swung in the water. This oscillation is the movement of the bait. For example, the bait can be shaken by shaking the underwater holding means by hand. It is also possible to shake the bait with the water flow inside the aquaculture tank. Furthermore, by making the underwater holding means easy to shake, the cephalopod can also shake when it comes into contact with the bait. Alternatively, it can be carried out by shaking the underwater holding means using a swinging means. By rocking the bait held in this underwater holding means, feeding behavior of the cephalopod can be induced. This allows the bait to move underwater, attracting the cephalopod's interest and stimulating its feeding activity. This oscillation may be, for example, about 5 mm to 5 cm, as long as it oscillates in any direction underwater, such as front, back, left, right, up and down, and the period of the oscillation is such that the distance is covered in about 1 to 5 seconds. can do.

[Owing means]
In the present invention, the "swinging means" is for swinging the bait held in the underwater holding means. The feeding method of the present invention can include a step of shaking the bait in the water in the step of holding the bait in the water. Since it is sufficient that the bait swings as a result, it is also possible to swing the string-shaped body, rod-shaped body, etc. to which the bait is attached, or the underwater holding means itself to which the hanging string is fixed. There are no particular limitations on the rocking method, and the rocking target part (bait, hanging string, hanging means, etc.) can be moved continuously or intermittently using a cylinder, pendulum, motor, vibrator, pump that generates water flow, etc. alone or as appropriate. Depending on the combination, it is possible to use one that shakes the bait.

[Cephalopod]
The "cephalopods" to be fed by the feeding method and feeding device of the present invention belong to the class Mollusca. The present invention can be applied to all cephalopods that are subject to cultivation and rearing. Specific examples include spear squid, bluefin squid, cuttlefish, common octopus, green octopus, water octopus, and octopus maya.

In particular, the cephalopod to be fed in the present invention is preferably a member of the superfamily Octopus, more preferably a member of the family Octopus of the superfamily Octopus, and preferably a octopus of the family Octopus. The octopus is eaten as food, especially in Japan, and is a marine organism for which it is desired to establish complete aquaculture technology. The feeding method of the present invention is very suitable for complete cultivation of this octopus, and the octopus is good at feeding on the food held by the underwater holding means as in the present invention.

The octopus hatches in about a month after being laid, and weighs about 0.05g at this time. Approximately 80 days have passed since spawning, and when the octopus reaches a weight of approximately 3 to 5 g, it begins to live a benthic life, and this initiation of benthic life is called bottom settling. The period of approximately 30 to 80 days after spawning, from hatching to landing on the bottom, is called the floating period. During this floating stage, the octopus has a body length of approximately 4 to 8 mm. Although the feeding according to the present invention is effective even for octopus after they have landed on the bottom, it is particularly suitable for octopus during the floating period.

This floating period is also a time when it is difficult for octopus to grow, but according to the present invention, the octopus can feed efficiently during the floating period, which can also contribute to improving the growth rate and survival rate. In addition, the feeding according to the present invention, including feeding during the floating period, may be used in combination with feeding using other scattered baits, biological feeds, etc. The feeding according to the invention can also be used in combination with biological feeds and/or compound feeds.

[feed]
In the present invention, the "bait" held in the underwater holding means can be any of various baits used as bait for cephalopods. In particular, solid baits are used because they are held in underwater holding means. As such bait, raw materials such as small fish, shellfish, fish meat, shellfish meat, squid meat, and livestock meat can be used. In addition to these, casein, gluten, gelatin, starch, alginic acid molding agents, fish meal, squid meal, meat meal, etc., as well as oils and fats, various extracts, vitamins, minerals, etc., are mixed as appropriate and kneaded and molded. can be used.

[First embodiment]
FIG. 1 shows a schematic diagram of a first embodiment of a feeding device of the present invention. FIG. 1 is a diagram showing a state in which the feeding device 11 is used for cultivating octopuses 5. In this feeding device 11, the bait 1 is fixed to a hanging string 21 of a hanging holding means, and is suspended in the culture water 4 of the culture tank 3, so that the bait is held in the water. This hanging cord 21 is fixed to a hanging cord fixing part 211. This hanging cord fixing part 211 is made into a rod-shaped body because the more rigid it is, the better the distance between the plurality of hanging cords 21 can be maintained, and the ease of handling such as collection and placement can be improved. In this feeding device 11, a swinging device 6 is attached to a hanging string fixing portion 211, and by swinging the hanging string fixing portion 211 and the hanging string 21 by the swinging device 6, the feeding device 11 is fixed to the hanging string 21. It is also possible to oscillate the bait 1. According to such a feeding device, bait is held in water and cephalopods such as octopuses can efficiently feed.

[Second embodiment]
FIG. 2 shows a schematic diagram of a second embodiment of the feeding device of the present invention. FIG. 2 is a diagram showing a state in which the feeding device 12 is used for cultivating the octopus 5. In this feeding device 12, the bait 1 is fixed to a support holding means 22, and is held in the culture water 4 of the culture tank 3. This support holding means 22 is a string-like body, and is arranged to span across the sides of the culture tank 3. A swinging device 6 is connected to the string of the support holding means 22 in this feeding device 12, and the bait 1 can also be swung by the swinging device 6. According to such a feeding device, bait is held in water and cephalopods such as octopuses can efficiently feed.

[Third embodiment]
FIG. 3 shows a schematic diagram of a third embodiment of the feeding device of the present invention. FIG. 3 is a diagram showing a state in which the feeding device 13 is used for cultivating the octopus 5. In this feeding device 13, the bait 1 is fixed to a support holding means 23, and is held in the culture water 4 of the culture tank 3. This support holding means 23 is a rod-shaped body, and has a configuration in which the bait 1 is fixed to the tip or the middle portion thereof, and the bait 1 is supported from the bottom surface side. A swinging device (not shown) can also be attached to this feeding device 13 to swing the bait 1. According to such a feeding device, bait is held in water and cephalopods such as octopuses can efficiently feed.

EXAMPLES Hereinafter, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to the following Examples unless the gist thereof is changed.

The hatched octopus was cultured in a culture tank until it was 100 days old. Approximately 500 octopus were cultured in a culture tank with a volume of 500 L. Squid locusts were used as bait to be fixed to the hanging string.

[Example 1]
Using an underwater holding means using a hanging string similar to the configuration shown in Figure 1, bait is suspended from the hanging string and fixed at a distance of 3 to 10 cm from the water surface and approximately 50 cm from the bottom surface, and while being fed, the feeding state of the octopus can be monitored. observed. The fishing line was fixed to a tree. The octopus was reared in seawater at a temperature ranging from 17 to 23°C.

[Aquaculture results] The following conditions were mainly observed during aquaculture. The state of growth and presence or absence of bottoming were determined visually. Mortality was also determined visually. The bottom landing rate was calculated as the ratio of the number of individuals that landed on the bottom out of the number of individuals introduced into the aquarium.
At 25 days after the start of feeding, it was confirmed that the octopus was eating enough food so that the food filling its stomach was visible. In addition, when using a feeding method such as the comparative example described below, the feeding behavior was completed within 1 to 2 minutes, and no individual was observed whose stomach was filled with food. The octopus ate while attached to the bait fixed to the hanging string, and when it separated from the bait, it continued to feed by attaching to the bait again.
Similarly, 25 days after the start of feeding, it was confirmed that when the food was fed manually with rocking, the octopus were more likely to gather on the food and the food decreased faster than when the food was not rocked.
Also, during aquaculture, food does not accumulate on the bottom of the tank, so there is less contamination, and there is no need to clean the bottom of the tank. Furthermore, after 100 days had passed, the number of octopus that had landed on the bottom was approximately 28.

[Comparative example 1]
The same amount of bait as in Example 1 was sprinkled and fed at a frequency of 2 to 3 times/day without being fixed with a hanging string. However, if the bait was spread in the same size as in Example 1, it would immediately settle, so the bait was cut into pieces of about 2 mm before feeding.

[Aquaculture results] The following conditions were mainly observed during aquaculture. The state of growth and presence or absence of bottoming were determined visually. Mortality was also determined visually. The bottom landing rate was calculated as the ratio of the number of individuals that landed on the bottom out of the number of individuals introduced into the aquarium.
When the bait was not fixed using a hanging string, most of the bait was not consumed and settled at the bottom of the tank. When the octopus feeds, it feeds while floating in the water of the culture tank, but the feeding time is short, and when the food is released, the food settles, and it re-feeds the food that has settled to the bottom of the culture tank. There was nothing to do. Furthermore, after 60 days had passed, 5 octopus had settled on the bottom, but the number of octopus produced was small, and after 100 days had passed, the number of surviving octopus was about 0.

As is clear from the results of the Examples and Comparative Examples, the octopus fed according to the present invention had a high rate of landing on the bottom, and many of the individuals grew to a size sufficient to land on the bottom within 80 days. On the other hand, in the comparative example of feeding by scattering bait, the bottom landing rate was low and the growth was slow.

The present invention is excellent as a feeding method and a feeding device for cephalopods. According to the present invention, feeding of cephalopods that are difficult to farm can be carried out efficiently, contributing to improvement of aquaculture efficiency, etc. It is very useful.

1 Bait 11, 12, 13 Feeding device 21 Hanging string 211 Hanging string fixing part 22, 23 Supporting and holding means 3 Aquaculture tank 4 Aquaculture water 5 Octopus 6 Rocking device

Claims (13)

A method for feeding an octopus, the method comprising the steps of: retaining the bait in water using an underwater holding means for retaining the bait in the water of a culture tank; and allowing the octopus to feed the bait. The feeding method according to claim 1, wherein the step of holding the bait underwater by the underwater holding means includes the step of shaking the bait underwater. 3. According to claim 1 or 2, the step of holding the bait underwater by the underwater holding means includes the step of suspending the bait by a hanging holding means for suspending and holding the bait in the water from the opening of the culture tank. Feeding method as described. 4. The feeding method according to claim 3, wherein the suspension holding means includes a string-like body or a rod-like body to which the bait is attached. Claim: The step of holding the bait underwater by the underwater holding means includes the step of holding the bait by a support holding means for attaching the bait to a support disposed in the culture tank and holding it underwater. The feeding method according to 1 or 2. 6. The feeding method according to claim 5, wherein the support and holding means includes a string-like body or a rod-like body suspended within the culture tank. 6. The feeding method according to claim 5, wherein the supporting and holding means includes a rod-shaped body disposed within the culture tank. The feeding method according to claim 4 or 6, wherein the string-like body is at least one string-like body selected from the group consisting of fishing line, kite line, sewing thread, and wire. 8. The feeding method according to claim 4, wherein the rod-shaped body is at least one rod-shaped body selected from the group consisting of a cylindrical body, a columnar body, and a cone-shaped body. 10. The feeding method according to claim 1, wherein the bait is spaced apart from the bottom of the culture tank. A method for cultivating octopuses, which comprises applying the feeding method according to any one of claims 1 to 10 to cultivating octopuses at least in the floating larval stage. A feeding device for an octopus, comprising a food holding means for holding food in water in a culture tank at a distance from the bottom of the culture tank, the food holding means holding the food in water at a distance from the bottom and/or side of the culture tank. A feeding device for octopuses that is a supporting and holding means that is attached to a support that is a rod-shaped body that is attached to a part of the body and held underwater . The octopus feeding device according to claim 12, further comprising a swinging means for swinging the bait held in the bait underwater holding means.