JPH08116887A - Method for culturing loach fry - Google Patents

Abstract

PURPOSE: To raise survival rate and to improve yield of loach by raising loach fries by using Brachinous calysiflorus as a feed for culture. CONSTITUTION: Loach fries are raised by using Brachinous calysiflorus as a feed for culture. Brachinous calysiflorus highly contains a carotenoid such as canthaxanthin, (3S)-phenicoxanthin or (3S,3'S)-astaxanthin and the feed improves hatching and occurrence of eggs and growth of fries more than a formula feed and egg yolk.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for cultivating juvenile loach larvae and an improvement in feed for aquaculture.

[0002]

2. Description of the Related Art Conventionally, artificial mixed feed, egg yolk, etc. have been used in aquaculture such as seedling production of loach.

[0003]

However, when fry larvae are bred with these feeds, the actual yield is poor.

An object of the present invention is to provide a method for cultivating juvenile loach larvae and a feed for the same, which has a high survival rate and a good yield when rearing larval loach larvae.

[0005]

[Means for Solving the Problems] Reactive oxygen is generated during the process of hatching, development and growth of larvae of fish. Antioxidants are needed to remove this.

When a carotenoid having an active oxygen scavenging action such as astaxanthin is administered to red sea bream, salmon, trout, etc., it is considered that the hatching and development of eggs and the growth of larvae are improved.

Therefore, it is preferable to add carotenoids such as astaxanthin to the compounded feed.

On the other hand, in the case of larvae and juveniles, natural feed is easier to feed than mixed feed and water pollution in fish farms is less.

From the above, micro-organisms (plankton) containing antioxidant substances such as carotenoids are preferable for the cultivation of loach larvae.

Then, when various micro organisms (plankton) were examined, the rotifer (scientific name: Brach)
It has been found that inactive calciflorus) contains a high content of carotenoids having active oxygen scavenging activity such as astaxanthin.

Furthermore, when juvenile loach larvae were reared using the rotifer as feed, it was revealed that the survival rate was higher and the yield was drastically improved as compared with the mixed feed group, egg yolk and the like.

The present invention relates to the rotifer Brachino
A method for cultivating juvenile loach larvae, characterized by using us caliciflorus as a feed for aquaculture, and a feed for cultivating juvenile loach larvae characterized by containing rotifer.

Table 1 shows the carotenoid composition, which is a component of the rotifer, and Table 2 shows the tocophenol composition. The components were identified by extracting the rotifer with acetone and separating each component by column chromatography, followed by UV and visible absorption spectra (UV).
-VIS), electro-impact mass spectrum (E
I-MS), hydrogen nuclear magnetic resonance spectrum ( ¹ H-NM
R), circular polarization dichroism spectrum (CD).

[0014]

[Table 1]

[0015]

[Table 2]

That is, from Table 1, canthaxanthin,
A new finding was obtained that carotenoids having an active oxygen scavenging activity such as (3S) -phenicoxanthin and (3S, 3 ′S) -astaxanthin are contained as main components.

Further, (3S) -phenicoxanthine,
It was revealed that (3S, 3'S) -astaxanthin mainly exists in the rotifer body in the ester form with fatty acids. In fish, ester type carotenoids are more easily absorbed and more stable than the free type.

On the other hand, the active oxygen scavenging activity of the ester type carotenoid is weaker than that of the free type carotenoid, but when inoculated as a food, it is hydrolyzed in the digestive tract and converted into the free type, so that it is in vivo. It exhibits the same activity as the free form. The rotifer also contains a high content of tocophenol, and the effects of these active oxygen scavenging active substances are also exhibited.

The chemical structural formulas of β-carotene, echinenone, canthaxanthin, (3S) -phenicoxanthin and (3S, 3 ′S) -astaxanthin found in the table are as follows. In addition, R = H (free type), R
= Acyl (ester type).

[0020]

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[0021]

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[0022]

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[0023]

[Chemical 4]

[0024]

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[0025]

The method for cultivating juvenile loach larvae of the present invention is a method for culturing larval loach, Brachinous calyciflorus, as a feed for aquaculture. The survival rate is high and the yield is dramatically improved.

Further, since it is a natural feed, in the case of larva and fry, it is easier to feed than artificial blended feed, and the water quality of the fish farm is less polluted.

In addition, it can be used as a natural active oxygen scavenging active substance, and it has a protective effect on all living bodies having cell membranes composed of higher unsaturated fatty acids which are susceptible to the action of active oxygen. Its usefulness such as livestock feed and food additives is extremely large. Specifically, as aquatic food additives, in addition to loach, eel, Iwana, Amago, Niji, salmon, Funa, squid, Ugui, Lotus, Moroko, Gori, Koi, Ayu, Yamame It is useful for high-grade freshwater fish and crustaceans. Also, as livestock feed,
Cow, pig, chicken, goat, sheep, duck, duck etc. have the same effect. Addition to pet food is also useful. Also, when added to food, it exerts a protective action against active oxygen like tocophenol and ascorbic acid.
It is also useful for digestive, respiratory, circulatory, cerebrovascular disorders, etc. against various inflammations.

[0028]

[Example] For the cultivation of loach, conventional mixed feed, egg yolk,
The survival rate of the larvae of the loach loach after 14 days of breeding was measured by using the above-mentioned and rotifer as feeds. As the conventional compounded feed, the Nissin carp compounded feed and C for Yamato fry were fed at a rate of about 2 g / day per 10,000 loach larvae.
Egg yolk was fed at a rate of about 5 g / day per 10,000 loach larvae. This egg yolk is fed with a 0.2 mm mesh passing material. 10-20 tsubo rotifers / m
They were fed at a density of 1 l.

Table 3 below shows the results.

[0030]

[Table 3]

As shown in Table 3, when the rotifer was used, a remarkable improvement in the survival rate (yield) was recognized as compared with the mixed feed group and the yolk group.

It is considered that this improvement is due to the fact that carotenoids and active oxygen scavenging active substances such as tocophenol, which are contained in the rotifer in high content, are involved in the improvement of the growth of juvenile loach larvae.

[0033]

EFFECTS OF THE INVENTION Since the present invention is a method of cultivating juvenile loach larvae, which uses the rotifer as a feed for aquaculture, the survival rate is higher than that of conventional artificial compounded feeds and egg yolks when breeding larvae. Is high and the yield is dramatically improved. In addition, since it is a natural feed, larvae are easier to feed than artificial blended feeds, and water pollution in fish farms is small.
The active oxygen scavenging active substance obtained from the rotifer can be used as a natural active oxygen scavenging active substance for various uses such as feed for fisheries and livestock, and food additives.

Claims (4)

[Claims] 1. The rotifer Brachinous ca
A method for culturing loach larvae, which comprises using lyciflorus as a feed for aquaculture. 2. The rotifer Brachinous ca
A feed for aquaculture of loach larvae characterized by containing lyciflorus. 3. The rotifer Brachinous ca
A natural active oxygen scavenging active substance obtained from lyciflorus. 4. An aquatic feed additive containing the active substance for eliminating natural active oxygen according to claim 3 as an active ingredient.