JP2003299422A - Method of culturing water flea - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of efficiently culturing water fleas by mixing effective microorganisms (EM) to the feed or culture water as a good environment for growing water fleas is retained. <P>SOLUTION: The feed for water fleas, effective microorganisms and salts are added to the culture water in a water tank and they are aerated to prepare the environment for growing water fleas. Then, seeds of water fleas are inoculated and cultured as prescribed amounts of the feed and the effective microorganisms are charged. After the cultivation is continued for a prescribed period of time, the grown water fleas are collected. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for cultivating Daphnia magna.

[0002]

2. Description of the Related Art In the field of fisheries, zooplankton such as Daphnia is used as a live food for hatched fry such as carp and goldfish. These Daphnia are cultivated by fertilizing or feeding an organic fertilizer such as chicken dung, oil cake, soy sauce cake and the like. It is known that baker's yeast is effective for feed for Daphnia, and recently, unicellular green alga Chlorella and the like have been used as feed. Among the Daphnia magna, the Daphnia magna has a high growth rate and can be cultivated relatively easily, and is therefore widely cultivated in aquaculture sites.

[0003]

However, in the conventional culture of Daphnia magna, it is difficult to maintain a good growth environment (because it requires a large water surface and a large amount of water, and its growth depends on the weather). And over the long term,
There is a problem that it is difficult to obtain a stable culture amount. Further, in the batch-type culture in the water tank, there is a problem that the ammonia concentration increases with the lapse of the culture period and the culture is inhibited. The present invention has been made to solve such conventional problems, and the purpose thereof is to improve the growth of Daphnia magna by mixing a useful microorganism group (EM bacterium) in feed or culture water. It is intended to provide a method for cultivating Daphnia magna that efficiently cultivates while maintaining the environment.

[0004]

[Means for Solving the Problems] In the method for cultivating Daphnia magna according to claim 1 of the present invention as a means for achieving the above object, a useful microorganism group (EM bacterium) is mixed and fermented in a feed of Daphnia magna, and The fermentation product was used as a feed.

In the method for cultivating Daphnia magna according to claim 2,
Feed of Daphnia magna and useful microorganisms (EM
Bacterium) is added, the feed of Daphnia magna is fermented in the culture water by the action of the useful microorganism group (EM bacterium), and the fermentation product is used as the feed.

In the method for cultivating Daphnia magna according to claim 3,
Feeding daphnia, useful microorganisms (EM
Bacteria), salt is added to perform aeration to prepare a growth environment for daphnia, then seed daphnia is introduced, seed daphnia is introduced, and then a predetermined amount of feed and useful microorganisms (EM bacteria) are introduced. The culture was carried out, and after the lapse of a predetermined period, the daphnia was harvested.

In the method for cultivating Daphnia magna according to claim 4,
On the first day, the useful microorganisms (EM bacteria) are added to the culture water for aeration, and on the second day, the daphnia feed and salt are added for aeration, and on the third day, the useful microorganisms (EM bacteria) are further added. ) Is added for aeration, and on the 4th day, seed Daphnia is added and 5
On the 10th day, while feeding the feed and useful microorganisms (EM bacteria) while cleaning the bottom of the tank, on the 11th to 17th days while feeding the feed and useful microorganisms (EM bacteria) In this method, a predetermined amount of Daphnia is harvested every day.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Among the small-scale crustaceans of zooplankton, which are mainly freshwater, the claritones are collectively called daphnia. These Daphnia live widely in still waters such as Ikenuma,
There are many species, but long ago
ocopa) is used by fish farmers. Daphnia proliferate in the spring and summer in the natural world, spend the rest of the year between dormant eggs in the fall and winter and wait for the next spring. Proliferate in (female only). The produced Daphnia magna becomes a parent in 3 to 4 days and gives birth to the next generation. The present invention provides these Daphnia with a group of useful microorganisms (EM
Bacterial flocs (lumps of bacteria) produced using bacteria are fed as feed and cultured.
In the culture tank, aeration is performed through a vinyl chloride tube to create a slow flow of water in the same direction with minimal physical stimulation to Daphnia so that oxygen can be uniformly supplied into the culture tank. In addition, a salt (natural salt) is added to the culture water to maintain the physiological activity of Daphnia. In order to prevent the increase of ammonia concentration in the culture water, a circulation filtration system is installed in the culture tank to clean the bottom.

Group of useful microorganisms (EM bacteria) used in the present invention
Is the English name of useful microorganisms Effectiv Microorganisms
It is a word consisting of the acronym "Effective Microorganisms", and is a microbial material in which more than 80 safe and useful microorganisms are symbiotic. This EM bacterium has the property of changing the environment of microbial flora in soil or water to a state favorable for living things. These EM bacteria include photosynthetic bacteria, actinomycetes, yeasts, lactic acid bacteria, filamentous fungi and the like, and also include bacteria that decompose ammonia to render it harmless. This EM bacterium is bottled and sold, and it is available at gardening stores, etc. As an example, Scion EM1 (Okinawa Prefecture: Sun Kogyo Co., Ltd.), EM-1 (Shizuoka Prefecture: EM Laboratory) Can be used.

[0010]

EXAMPLES Examples of the present invention will be described below. The culture tank is a water tank of 1.8 m x 3.6 m x 0.6 m with a wooden frame and a wooden frame, and the amount of water used is 2.6 t. The aeration system puts air stones inside a PVC pipe with a diameter of 100 mm, installs diffusers with elbows at the top at the four corners of the culture tank, and supplies oxygen to the culture water flowing in from the bottom of the PVC pipe. By making a part of the elbow above the surface of the water and adjusting the direction of its outlet, a weak clockwise water flow is created. A 45-liter garbage bucket was installed in the filtration tank, and the filter medium had a two-layer structure of charcoal in the lower part of the bucket and zeolite in the colander in the upper part. The culture water has a diameter of 50 attached to the side of the bucket.
It is constantly pumped up by an air lift of a polyvinyl chloride pipe of mm, and drained in the same direction as the water flow in the culture tank through the opening formed in the bottom surface of the bucket. Since the generation of microbial biofilm is remarkable in the main culture system, it is necessary to regularly clean both the aeration system and the filtration tank. In the Daphnia culture of the present technology, most of the existing breeding facilities and breeding tanks can be used by using the above system.

Culturing is carried out using the above-mentioned culture tank by the following procedure. On the first day, 1/1000 (0.1% by weight) of the useful microorganism group solution (EM bacteria) is added to the new culture water, and aeration is performed overnight to supply oxygen. As the EM bacterium, the above-mentioned E
M1 (Okinawa Prefecture: manufactured by Sun Kogyo Co., Ltd.) and EM-1 (Shizuoka Prefecture: manufactured by EM Laboratory) are used. The addition amount can be changed to some extent depending on the water temperature, water quality, etc. The amount of the useful microorganisms (EM bacteria) added is such that the EM bacteria are propagated in the culture tank within a range that does not impair the growth environment of Daphnia magna.

On the 2nd day, 4 feeds of Daphnia fermented by applying useful microorganisms were fermented.
It is added to the culture water at a rate of 50 g / t, and the useful microorganism group solution is added in an amount of 1/1000 (0.1% by weight) of the amount of the culture water and a salt in an amount of 9/1000 (0.09% by weight) of the amount of the culture water. .
The feed for Daphnia magna which is developed by applying the group of useful microorganisms is an organic substance such as chicken dung, soy sauce cake, oil cake, etc., mixed with EM bacteria and fermented for several days. Hereinafter, this feed will be used. As this fermentation treatment, a suitable amount of liquid EM for organic matter is used.
For example, by mixing the bacteria and fermenting them for several days while stirring. In this example, fermented feed is used,
The effect of culture can be obtained even when using a feed that has not been fermented. Next, aeration is performed well, and the feed that has settled on the bottom of the tank is stirred twice or more in the morning and evening to promote the elution of the components into the culture water and the fermentation and digestion by the useful microorganisms. In addition, all the daphnia feeds to be added are put in a net material such as stockings and are eluted by massaging in culture water. As a result, the feed is subdivided and diffused into the culture water.

On the 3rd day, a large amount of microorganisms propagate by the addition of feed and salt. Stir the bottom of the tank at least twice in the morning and evening. A useful microorganism group solution is added in an amount of 1/5000 (0.02% by weight) of the culture water amount.

On the 4th day, the culture water is suspended. When the culture water suitable for culturing Daphnia magna was prepared, the seed Daphnia wet weight of about 100 g / 2.
6t (there is a quick rise when there are many species) is transplanted to a culture tank, and the useful microorganism group solution is added to 1/5000 (0.02
(% By weight), and stir the bottom of the tank twice or more in the morning and evening. The wet weight of 100 g of the daphnia contains about 500,000 individuals of the parental and offspring generations. The amount of seed daphnia added can be changed depending on the water temperature, water quality, and the like.

From the 5th to 10th days, from around the 6th day, the feed for Daphnia magna is added to the culture water at a rate of 150 g / t every day while observing the suspension state of the culture water. Useful microorganism group solution is 1/5000 of culture water volume every day
(0.02% by weight), and the bottom of the tank is stirred twice or more in the morning and evening. When a certain amount of sediment on the bottom of the tank has accumulated, the bottom is cleaned to remove the sediment. In bottom cleaning, the sediment is suctioned off, and the amount of water reduced by bottom cleaning is replenished.
If a black reduced layer is found in the sediment on the bottom of the tank, stop stirring and cleaning the bottom of the tank, do not stimulate the bottom of the tank, and minimize the increase in ammonia concentration in the culture water.

11th to 17th days The harvest of Daphnia magna starts. About 300g a day can be harvested every day for 5-7 days. The feed is added to the culture water at a rate of 150 g / t while checking the condition of the culture water every day during the harvest. The useful microorganism group solution is added daily 1/5000 (0.02% by weight) of the culture water. The culture is terminated when the yield of Daphnia significantly decreases.

The following water quality conditions can be maintained under the above culture conditions. Dissolved oxygen (DO): 4 ppm or more Hydrogen ion concentration (ph): 7 to 7.5 Ammonia (NH ₃ ): 0.25 ppm or less If the water temperature is 18 degrees or more, culturing is possible even in winter.

Next, the method for cultivating Daphnia magna according to the second embodiment will be described. In the method for cultivating Daphnia magna of the first embodiment, a method of introducing a feed and a group of useful microorganisms into the culture water and fermenting it is possible, but it is also possible to culture with only the fermented feed. That is, it is a method of fermenting an organic substance by the same method as in the first embodiment and culturing Daphnia magna only by the fermentation product. According to this method for cultivating Daphnia magna, it is possible to efficiently cultivate Daphnia magna by maintaining a good growth environment for Daphnia magna only by feeding fermented feed. The culturing method may be a commonly used method.

Although the embodiment of the present invention has been described above, the specific configuration of the present invention is not limited to this embodiment, and there are design changes and the like within the scope not departing from the gist of the invention. However, it is included in the present invention. For example, the system, shape, size, etc. of the culture tank described in the above embodiment can be set arbitrarily.

[0020]

INDUSTRIAL APPLICABILITY As described above, in the method for cultivating Daphnia magna according to the present invention, since the feed fermented with EM bacteria is fed, a feed having a high nutritive value corresponding to the growth of Daphnia magna is supplied. In addition, since the feed and the group of useful microorganisms are added to the culture water, the feed is fermented in the culture water and the feed suitable for the growth of Daphnia magna is produced. Further, the culture water is purified by the action of the useful microorganisms, particularly the generation of ammonia that is harmful to Daphnia magna is suppressed, and the generated ammonia is decomposed to maintain a favorable Daphnia magna growth environment.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Masayoshi Okada             Gunma Prefecture Ota City Niijima Town 607 Okada Fisheries F term (reference) 2B104 AA34 CA01 ED19                 2B150 AA07 AD02 BB01

Claims (4)

[Claims] 1. A group of microorganisms useful for feed of Daphnia magna (EM
A method for cultivating Daphnia magna which comprises fermenting mixed bacteria and feeding the fermented product as feed. 2. A feed of Daphnia magna and a group of useful microorganisms (EM bacteria) are added to the culture water of the aquarium, and the group of useful microorganisms (EM bacteria) is added.
A method for cultivating Daphnia magna which comprises fermenting a feed for Daphnia in culture water by the action of the above and using the fermentation product as a feed. 3. A daphnia feed, useful microorganisms (EM bacteria) and salt are added to the culture water of the aquarium for aeration to prepare a growth environment for daphnia, and then seed daphnia is introduced and seed daphnia is introduced. After that, the method for cultivating Daphnia magna which comprises culturing while feeding a predetermined amount of feed and a group of useful microorganisms (EM bacteria), and harvesting Daphnia magna after a lapse of a predetermined period. 4. A group of useful microorganisms (EM
Bacteria) to perform aeration, on the 2nd day feed of daphnia and salt to perform aeration, and on the 3rd day, more useful microorganisms (EM bacteria) are added to perform aeration, and 4th day The seed daphnia is added to, and on the 5th to 10th days, the feed and useful microorganisms (EM bacteria) are added while cleaning the bottom of the tank to grow, and on the 11th to 17th days, the feed and useful microorganisms are added. A method for cultivating daphnia, characterized in that a predetermined amount of daphnia is harvested daily while introducing (EM bacteria).