JPH0510B2 - - Google Patents

Description

[Detailed description of the invention]

"Industrial Application Field" The present invention relates to a method for cultivating pearls. ``Conventional technology'' Pearl cultivation methods have a long history, and since their inception many technical improvements have been made, and for many years the ``plane array cultivation method using net cages'' described below has been established as the mainstream. was. In other words, the culture net has a flat bottom so that pearl oysters that have undergone surgery to form pearls can easily absorb plankton and oxygen from the sea, and efficient intensive growth and recovery in the sea. The ``flat array aquaculture method'' was used, in which pearl oysters were stored in a flat array on the bottom of a cage and suspended horizontally into the sea for cultivation. However, pearl oysters cannot survive in the sea unless they attach themselves to something by putting out byssus threads, so they tend to attach themselves to each other with their byssus threads and form several clumps on the bottom of the net. The problem is that the pearl oysters that enter the clumps have poor contact with the current, resulting in nutritional deficiencies and weakening. In order to solve this problem, it is essential to periodically pull up the aquaculture net cage from the sea, loosen the shellfish clusters on the bottom of the net, cut the byssus threads individually, and remove harmful deposits. Because this work is time-consuming and difficult,
There were problems that significantly reduced the productivity and workability of pearl farming. Therefore, as an aquaculture method that solves the difficulties of the above-mentioned "plane array aquaculture method using aquaculture net cages", as shown in Fig. 2, aquaculture net chambers 7 divided vertically into steps
``Multi-stage, horizontal single-row vertical culture method using net bags'' uses vertically long aquaculture net bags 6, and stores several pearl oysters 1 side by side in a horizontal row in each culture net chamber 7, and suspends them in the sea for cultivation. '' was developed, and all pearl farming today is done using this method. ``Problems to be Solved by the Invention'' However, in this ``multi-stage horizontal single-row vertical culture method,'' groups of pearl oysters are cultured by storing them in a horizontal row in the culture net chamber 7, so pearl oysters are cultured by byssus. Although this method has the advantage of eliminating the drawbacks of the above-mentioned "flat array culture method" by not sticking to the net and forming nodules, the entire net surrounding the pearl oyster 1 contains sponges, sea squirts, corals, and barnacles.・A large amount of larvae such as Kasane Kanzaki breed, and these larvae also feed on plankton like pearl oyster 1, so pearl oyster 1 in the aquaculture net chamber 7 breeds attached to the net wrapped around it. The problem is that larvae such as sponges and sea squirts take advantage of oxygen and food, resulting in nutritional deficiencies that have a negative impact on pearl farming. The attached larvae may cause the entire culture net bag to appear wrapped in a blanket, causing the pearl oysters 1 to weaken and die. Furthermore, since this ``horizontal row vertical method'' arranges several groups of shellfish in parallel, shellfish in intermediate positions do not have sufficient contact with the current, which tends to cause poor growth. Therefore, even in the current mainstream "multi-stage horizontal row vertical culture method", the growth of pearl oysters is inhibited due to the pre-emption of oxygen and food by the attached larvae and poor growth due to parallel arrangement. Therefore, it is hard to say that the pearl culture performance is good (in cultured pearls, the number of pearl wraps increases in proportion to the growth of the Akoya oyster, and the number of high-quality parts increases in proportion to the thickness of the pearl wrap).
Moreover, complicated removal work of harmful larvae etc. that have been cultured on the culture is frequently required, which is a factor that reduces the productivity and workability of pearl culture. This has been a long-standing technical issue in the aquaculture field. The present invention has been made in view of the above circumstances, and aims to solve the problems of the prior art described above. ``Means for Solving the Problems'' The method for cultivating pearls of the present invention which achieves the above-mentioned objects is a method for cultivating pearls by retaining Akoya oysters in the sea in their exposed natural state without housing them in a net or a container. The basic idea is to cultivate fish, and it is structured as follows. Akoya oysters that have undergone surgery to form pearls are grown in the sea for pearl culture. Pearl cultivation is carried out by placing the feathers in pairs with their tips facing upwards, and gluing and fixing them individually at the required intervals in the vertical direction, and suspending the hanging belt vertically in the sea. The method of culturing pearls is characterized by the following. The present invention will be explained in detail below. First of all, the hanging belt is made by gluing pearl oysters and hanging them in the sea.
It has an elongated shape that allows a large number of pearl oysters to be glued and fixed vertically in steps at any desired pitch.It holds the glued shellfish groups sufficiently, and can withstand the work of putting the shellfishes into the sea while they are still glued, pulling them up, and tidal currents. A flexible belt body is used which has the mechanical strength required to achieve this purpose and is resistant to seawater and marine life, and the upper end of the belt body is attached to a pearl culture raft or the like so that it can be suspended in the sea. That is, the hanging belt is a belt-shaped one that meets the above requirements, and specifically, a woven fabric made of any material such as nylon, polyester, vinylon, cotton, polypropylene, polyethylene, vinyl chloride, silk, or wood. Any elongated body, mesh body, non-woven body, etc., which has a rectangular cross-sectional shape, is used, and the surface of the belt body is made of plastic such as polyurethane, polyester, or rubber material. - May be lined with a cushion layer made of natural fibers, etc. On the other hand, the adhesive used to attach pearl oysters to the above hanging belt is:
In addition to being sufficiently fixed to the hanging belt, the pearl oyster has an adhesive property that does not easily peel off due to handling of the hanging belt or ocean currents, and - Sufficient resistance to seawater and marine organisms. An adhesive that satisfies the above requirements, is not harmful to workers who work on removing adhesives from shellfish, and has fast curing properties that allow for efficient mass bonding was selected. Cyanoacrylate adhesives that react and cure instantly, two-component or one-component urethane adhesives, epoxy adhesives, radical polymerization adhesives, etc.
Any hot melt adhesive can be selected and used. Then, using a hanging belt and adhesive having the above requirements, pearl cultivation is carried out according to the following procedure. (1) Akoya oysters to be cultured are collected from the sea, and the byssus of the oysters is cut. (2) Clean the adhesive points of the pearl oyster. (3) Apply adhesive to the adhesive point and secure it in place on the hanging belt. Note that when adhering, the curing reaction of the adhesive becomes sensitive when there is excessive moisture in the air, such as on rainy days, so dry the adhesion points with an air gun or the like to ensure good adhesion.
In addition, the adhesion position of the pearl oyster is to place the wing tip of the shell (the tip where the two shells open and close) upward and the shell hinge downward, and select a part of the shell surface with less irregularities as the bonding point and hang it. In addition to ensuring good adhesion with the hanging belt, the part where the glued shellfish puts out its byssus in the sea to make it easier for the shellfish to fix itself to the hanging belt by itself. It is preferable to arrange the suspension belts so that they are close to each other. (4) Then, a hanging belt with Akoya oysters glued to it is suspended long into the sea, and the upper end is locked to hold it suspended, thereby cultivating pearls. "Operation" According to the pearl culturing method of the present invention having the above configuration,
Akoya oysters are not housed in containers such as nets or baskets, but are glued to belts suspended in the sea at intervals in the vertical direction, with most of the shells exposed except for the glued areas. Since the pearl oysters are kept in the sea, there are no physical harmful substances that can attract harmful organisms such as ascidians and sponges that take advantage of oxygen and plankton. is significantly improved. Therefore, the Akoya oysters are fattened with sufficient natural nutrition, and the rate of deterioration and death is extremely reduced. Pearl formation is actively promoted to cultivate thick, high-quality pearls with excellent luster and color. I can do it. An even more important effect is that since the pearl oysters are glued and fixed in opposite positions to a hanging belt narrower than the width of the shellfish, the byssus threads produced by the opposing pearl oysters intertwine and pull together.
This tension mutually stimulates the nacre-secreting cells present in each ovary, making each of them extremely active in forming pearls, leading to active pearl formation that cannot be achieved with other known pearl culturing methods. It has the effect of Then, the byssus threads are also attached to the hanging belt and instinctively improve their own fixing force, so the fixing force to the hanging belt becomes extremely strong, and the hanging belt is prevented by ocean current resistance etc. Falling off is almost prevented. In addition, only the hanging belt 2 is required to remove harmful organisms that adhere to and propagate.
Compared to the conventional culture net bag 6, the removal work is extremely simple, and workability and productivity are significantly improved. Regarding the harmlessness of the above adhesive, a research paper on the safety of the above cyanoacrylate adhesive on human skin was published on April 1, 1970 (Toho University's Journal of the Toho Medical Society, (Vol. 17, No. 2 reprint, April 1970), is not harmful when used on cultured pearls. "Embodiment" Hereinafter, an embodiment of the present invention will be described with reference to FIG. 1. This example is 25 mm wide and 1500 mm long.
A suspension belt 2 made of resin in the shape of a flexible thin plate of millet is used, and pearl oysters 1 are arranged in a pair of back-to-back pairs in a vertical row with a pitch P of approximately 200 millimeters. It is glued on the front and back sides. Then, glue the point 5 (approximately 5 millimeters in diameter) at a flat point in the middle of the less bulging surface of pearl oyster 1.
Then, arrange the pearl oysters 1 so that the wing tips 3 are upward and the shell hinges 4 are downward, and the backs are slightly shifted so that the convex parts of the pair of back-to-back shells are not in symmetrical positions. , using the above-mentioned cyanoacrylate adhesive 8 to instantly bond and fix (approximately 5
The upper end of this hanging belt 2 was fixed to a pearl raft and the pearls were cultured by suspending it in the sea. The pearl oyster 1 of this embodiment has a shell width of about 50 mm with the wing tip 3 facing up, and is glued to a hanging belt 2 with a width of 25 millimeters. Approximately 1/2 of them are closely facing each other. After the pearl oyster 1 adhesively fixed to the hanging belt 2 of the above embodiment is suspended in the sea, by nature, the pearl oyster 1 puts out byssus 9 to further fix itself to the hanging belt 2. Since they are also fixed to each other by the byssus threads 9, the locking force in the sea is sufficient, and in addition, the mutual byssus threads 9 of the opposing pearl oysters 1 are entangled and pulled together, To cultivate a large quantity of high-quality pearls by stimulating the nacre-secreting cells thereby producing the above-mentioned effect of activating pearl formation, and maintaining this state until the cultivation is completed without a single drop falling into the sea. was completed. The comparison results of pearl culture between the embodiment of the present invention, which was carried out using 10,000 pearl oysters of the same origin in the same time period, and the conventional method, ``multi-stage horizontal single-row vertical culture method'', are shown below. It is as shown in the table.

[Table] As described above, according to the pearl culturing method of the present invention, the diameter (rolling thickness) and harvested weight of pearls are increased, and the mortality rate during culturing is reduced, compared to the conventional method. This has the special effect of improving the pearl harvesting rate and increasing the proportion of high-quality pearls, which clearly shows the existence of the above-mentioned unique effects of the present invention. Furthermore, according to the pearl culturing method of the present invention,
Since the work of removing adherent propagation materials of harmful organisms during cultivation becomes extremely simple, the productivity and workability of pearl cultivation are particularly improved, and there is an advantage that cost reduction and labor saving can be significantly promoted. "Effects of the Invention" As explained above, the pearl culturing method of the present invention not only has excellent pearl culturing performance, but also significantly improves the workability and productivity of pearl culturing, thereby revolutionizing pearl culturing technology. It has an excellent effect of improving and improving.

[Brief explanation of the drawing]

Fig. 1: Shows a pearl culturing method according to an embodiment of the present invention, A is a perspective view showing a state in which Akoya oysters are adhesively fixed to a hanging belt, B is an enlarged partial side view of A, Fig. 2: Conventional method A front view showing a pearl culturing method. Code: 1...Akoya shell, 2...Hanging belt,
3... Shellfish wing tip, 4... Shellfish hinge, 5... Adhesion point, 6... Aquaculture net bag, 7... Aquaculture net chamber, 8...
Adhesive, 9... Byssus thread.

Claims (1)

[Claims] 1. When pearl oysters that have undergone surgery to form pearls are grown in the sea for pearl culture, the Akoya oysters are placed on both sides of a flat hanging belt with a width narrower than the width of the Akoya oysters. The pearls are made into a pair by facing each other with the tips of the wings facing upward, and are individually glued and fixed at a required interval in the vertical direction, and the hanging belt is suspended vertically in the sea and held. A method of culturing pearls characterized by culturing them.