JPH04126041A - Feeding stimulating substance of fishes and shellfishes and feed - Google Patents

Abstract

PURPOSE:To promote intake of fishes and shellfishes with a small amount of a feeding stimulating substance and to improve growth by adding a specific (un)saturated fatty acid to a feed base raw material. CONSTITUTION:A feed base raw material is blended with 10<-9> to 1M 18C, 20C, 22C or 24C (un)saturated fatty acid (e.g. oleic acid) and optionally 10<-9> to 1M dimethylpropiothetin shown by the formula (X<-> is monovalent anion).

Description

DETAILED DESCRIPTION OF THE INVENTION "Industrial Application Field" The present invention relates to a feeding stimulant and feed for fish and shellfish that increase the amount of feed taken by fish and shellfish and promote growth.

"Prior Art" Lipids contained in fish and shellfish feed are extremely important as an energy source and essential fatty acid source for sustaining the life of fish and shellfish. Various studies have been conducted on the essential fatty acids of seafood, and it has become clear that the essential fatty acids that are colored in freshwater are linoleic acid and linuric acid, and the essential fatty acids of saltwater fish are eicosabencitric acid and docosahexaenoic acid. ing.

Deficiency of these fatty acids slows or stops growth and causes various diseases, but in reality, as long as fresh commercially available compound feed or raw feed is used, deficiency of essential fatty acids is unlikely to occur. No attempt has been made to utilize essential fatty acids by actively adding them to feed compositions.

On the other hand, in recent years, in the aquaculture industry, efforts have been made to improve feed composition to increase so-called feed efficiency, which allows normal or higher growth with less feed, and to achieve feed efficiency equivalent to mixed feed using raw feed, fishmeal, etc. It is desired to develop alternative feeds to maintain this condition. The present inventors have conducted extensive research into a substance that stimulates the feeding of fish and shellfish, and a feed that has the effect of stimulating the sense of smell and taste of fish and shellfish to encourage them to eat the food. , has already been published in JP-A-631467.
No. 58, JP-A-63-192350, JP-A-1-20
No. 2260, JP-A-1-169457, JP-A-244
He has made many proposals such as No. 5460 and JP-A No. 2445461.

[Problem to be Solved by the Invention J These feeding stimulants are effective to some extent, but they are not limited to these, and it is possible to create new feeding stimulants or to further enhance the effects of the above feeding stimulants. It is desired to develop a substance that increases this level.

The present invention has been made in view of the above-mentioned state of the prior art, and its purpose is to create a new feeding stimulant for fish and shellfish that has not been discovered so far, and a feed stimulant by utilizing the feeding stimulant. The aim is to provide feed with increased efficiency.

[Means for Solving the Problems J In order to achieve the above object, the present inventors have conducted extensive research and found that CIll) C20, Czz, C24
The saturated and/or unsaturated fatty acids of C18, C2 promote the feeding and growth of seafood.
The present inventors have discovered that the effects are synergistically improved by using saturated and/or unsaturated fatty acids such as 0, C22, and Ca4 in combination with dimethylprobiotetin, and have completed the present invention.

That is, the seafood feeding stimulant of the present invention is CIa
, C2Q , C22+ C24 saturated and/or unsaturated fatty acids.

Further, another seafood feeding stimulant of the present invention is C
ue, Cz. , Cxi, C24 (7) at least one selected from saturated and/or unsaturated fatty acids,
It is characterized by consisting of a combination with dimethylpropiotetin.

Furthermore, the feed of the present invention includes a feed base material for seafood,
C,-,Ca. , C12) at least one selected from Ca4 saturated and/or unsaturated fatty acids.

Furthermore, another feed of the present invention comprises a feed base material for seafood, at least one selected from saturated and/or unsaturated fatty acids such as C18, C20, Caw) Ca4, and dimethylpropiotethine. It is characterized by

In addition, (:+s)C20)Cz in the present invention
z, C24 saturated and/or unsaturated fatty acids include the above-mentioned essential fatty acids, and there are reports that these essential fatty acids act as feed stimulants, thereby increasing feed efficiency. I can't find l/X.

Hereinafter, the present invention will be described in more detail by citing preferred embodiments.

In the present invention, CIa, C20, C22, C24
Specifically, the following saturated and/or unsaturated fatty acids are preferred.

That is, examples of saturated and/or unsaturated fatty acids for Cl8 include stearic acid, oleic acid, linoleic acid,
Preferred are lyllonic acid, etc., and as the saturated and/or unsaturated fatty acids of Cxo, araxic acid, eicosaenoic acid, eicosagenoic acid, eicosatrienoic acid, eicosatrienoic acid, etc. are preferred, and C2□ As the saturated and/or unsaturated fatty acids, behenic acid, docosahexaenoic acid, etc. are preferable, and as the C24 saturated and/or unsaturated fatty acids, lignoceric acid, nerponic acid, etc. are preferable.

Among these, C2o saturated and/or unsaturated fatty acids,
That is, arachidic acid and/or its unsaturated fatty acids are particularly preferred.
cid) is eicosanoic acid fEicosanoicac
Also known as idl, CH-(CHzl + 5cOOH
It is a saturated fatty acid represented by

These saturated and/or unsaturated fatty acids are present in animal and vegetable oils and can be separated and purified by conventional methods. Further, these saturated and/or unsaturated fatty acids are commercially available from Wako Pure Chemical Industries, Ltd., Yasu Pharmaceutical Co., Ltd., etc., and can be easily obtained by those skilled in the art.

In addition, in the present invention, C+s, C20, Cat
Dimethylpropiotetin used in combination with saturated and/or unsaturated fatty acids of Ci4 is a compound represented by the following structural formula.

CH.

＼ (In the formula, , C+e, C20, Cz□C24 saturation and/
Alternatively, it has been found that a synergistic effect can be brought about by combining with unsaturated fatty acids.

Dimethylpropiotetin can be easily synthesized by mixing and stirring 3-bromopropionic acid and dimethyl sulfide at room temperature for about 12 hours, washing with ether, filtering, and further crystallizing from methanol. . In addition, in the present invention, as dimethylpropiotetin, its salts such as bromine salt and chlorine salt may be used.

The feed of the present invention is the above-mentioned C., C. ,C22,C□
A feeding stimulant consisting of 4 saturated and/or unsaturated fatty acids or their combination with dimethylbropiotethine is obtained by adding to the feed base material.

In this case, any of synthetic feed, semi-natural feed, completely natural feed, etc. can be used as the base raw material. Specifically, the synthetic feed is cellulose powder, and the natural feed is ``Goldfish''. "Swimy Mini" (product name 1 made by Nippon Bet Food ■), "Aji Crumple" (product name 1 Nissin Feed ■) for sea bream, No. 1J for rburi mojako (manufactured by Oriental Yeast Kogyo ■) for yellowtail, etc. As the semi-natural bait, a mixture of synthetic bait and natural bait can be used.

The method of adding the above-mentioned feeding stimulant is not particularly limited, but
For example, a method of adding a solution containing the feeding stimulant to the feed base material and kneading the mixture can be preferably employed. In this case, C+s) Coo, Cwt, C24 saturated and/or unsaturated fatty acids are present in the feed composition as 10-@
It is preferable to add it to a concentration of ~1M, and dimethylpropiotetin is also added to the feed composition.
It is preferable to add it to a concentration of 9 to 1M.
In either case, if the concentration is less than 10-''M, a sufficient feeding stimulation effect on fish and shellfish cannot be obtained, and if it exceeds 1M, an odor is generated and the effect tends to decrease.
Since the saturated and/or unsaturated fatty acids H8, Co, Cz□, and C24 are oil-soluble, they are preferably dissolved in oil. As the oil, either vegetable or animal oil may be used, but animal oils with a high content of saturated and/or unsaturated fatty acids, especially fish oils such as sardine oil, can further enhance the feeding stimulation effect. It is preferably adopted for increasing

In addition, during feed preparation and storage, it is preferable to avoid oxygen as much as possible at low temperatures and in the dark in order to avoid deterioration due to oxidation.

"Effect" C, which is a feeding stimulant of the present invention. ,Cz
1 + Cz a saturated and/or unsaturated fatty acids are:
As shown in the experimental examples described below, it has the effect of stimulating the taste and smell of seafood in small amounts and increasing the appetite for seafood.
Furthermore, it was confirmed that it has the effect of promoting the growth of seafood.

In addition, the present inventors disclosed in JP-A No. 6
It has also been found that by combining dimethylpropiotethin, which was disclosed as a feeding stimulant for fish in No. 3146758, the feeding stimulating effect and the growth promoting effect are synergistically improved. Therefore, by adding these feeding stimulants, it is possible to enhance the feed effect in fish and shellfish farming. Furthermore, even with alternative feeds available at low cost, it is possible to maintain feed effects equivalent to those of mixed feeds using raw bait, horn powder, etc.

The feeding stimulant of the present invention has the effect of increasing the feeding amount of fish and shellfish and promoting their growth when added to various feeds such as synthetic feeds, semi-natural feeds, and completely natural feeds. . This effect is observed in all types of seafood, including freshwater fish such as carp, crucian carp, goldfish, eel, rainbow trout, and tilavia, and saltwater fish such as yellowtail, sea bream, and flounder.

The effect is also observed on shellfish such as turban shells, and crustaceans such as shrimp and crabs.

"Example" (1) Experimental method and apparatus FIG. 1 shows the apparatus used in the experiment on the feeding stimulation effect. In the figure, l is a water tank supported on a stand 2. A horn 3 is placed in a water tank 1. Aquarium 1
A pillar 4 is erected on the side of the recording needle 5, and an arm 6 connected to a recording needle 5 is rotatably supported by the pillar 4 via a support shaft 7. A thread 8 is connected to the rear end of the recording needle 5, and a magnet 9 is fixed to the lower end of the thread 8. When the magnet 9 is brought into close contact with the bottom of the water tank l, the thread 8 is stretched. In the part of the thread 8 immersed in the water of the aquarium L, there is a bait IO for the experiment.
is installed. On the other hand, a recorder main body 11 is installed on the side of the water tank l, and an inverted-shaped support 12 is erected on the recorder main body 11. Post 12 and recorder body 1
A one-rotation drum 13 is rotatably supported between the rotary drum 13 and the recording needle 5.
The zero-rotation drum 13, which is in sliding contact with the recorder body 11, rotates once every 2 minutes and 50 seconds by a drive mechanism (not shown) provided inside the recorder main body 11.

To explain the experimental method using the above-mentioned device, first, an experimental bait IO containing various feeding stimulants is prepared, the bait 10 is attached to the thread 8, and the intermediate height of water W11 is Place it in the correct position. Then, the rotary drum 13 is rotated to record the pecked state of the bait 10 by the fish 3. That is,
Fish 3 is bait l.

When the needle is pecked, the thread 8 stretched by the magnet 9 is pulled, the recording needle 5 swings, and recording is made on the rotating drum 13. In this way, the number of times the fish 3 pecked the bait 10 was measured while the rotating drum 13 rotated once. In addition, at the same time as replacing the test water for each test, the thread 8, the fish 3, and the tank 1 were thoroughly washed with breeding water.

Also, the size of the aquarium l is 20x 13x 14c+
If the fish is yellowtail, use 27x 16x
A 17 cm one was used.

Further, as the experimental water to be placed in aquarium 1, fresh water was used for freshwater fish, and artificial seawater in which ``Dry Marine'' (trade name, manufactured by Japan Biochemical ■) was dissolved was used for saltwater fish.

(2) Preparation of bait The bait for the test was prepared as follows. In other words, as bait pace raw materials, cellulose powder is used as a simple synthetic bait, and completely natural bait is used. As a semi-natural feed, a mixture of cellulose powder and the above-mentioned completely natural feed was used as a semi-natural feed.

On the other hand, a substance to be tested for feeding stimulation effect was added to corn oil.
An oily test solution was prepared by dissolving it to a concentration of 5mM.

Then, 0.05 wff of the above oily test liquid was added to 500 g of the above feed base material and mixed, followed by 0.0 g of water.
7■β was added and kneaded in a mortar to prepare bait. The feed prepared in this manner contains 0.016% of the substance to be tested for feeding stimulating effect per feed.

Preliminary test example (Effects of vegetable oil and animal oil on pecking behavior of golden and sea bream) Since the feeding stimulant of the present invention is oil-soluble, it is necessary to mix the feeding stimulant with the feed. It is preferable to dissolve it in vegetable oil or animal oil and then mix it into the feed base material.Therefore, for commercially available vegetable oils and animal oils, goldfish and sea bream pecks can be prepared by the above method. The effect on behavior was measured. In other words, for goldfish, we used a mixed feed consisting of a 3:1 mixture of cellulose powder and ``Swimmy Mini'' (trade name, manufactured by Nippon Het Food ■), and for sea bream, we used ``Aji Crumple'' (trade name, manufactured by Nisshin Feed ■). ) as feed base raw materials, and after adding and mixing 0.05 ■e of various oils to each 500 ■g of these feed base materials, water 0.7 + j! Add and knead,
Feed for the test was prepared. As a control, a feed prepared by mixing only water without adding oil was prepared. These baits were attached to the string of the device described above, and the number of pecks by goldfish was measured. Each test group was tested once, and the same test was repeated five times.

5 servings Table 1 shows the total number of repetitions.

Table 1 The results in Table 1 show that animal oils with a high content of highly unsaturated fatty acids, especially eicosapentaenoic acid and docosahexaenoic acid, have a greater effect on pecking behavior than vegetable oils with a lower content of C18 or higher fatty acids. Among animal oils, sardine oil is particularly effective in stimulating feeding intake.
Among vegetable oils, corn oil and palm oil are found to be high.

In the following examples, corn oil was used as the oil to dissolve the feeding stimulant, but when actually used as feed for aquaculture, purified oil, especially sardine oil, etc. can be used to increase the feeding stimulant effect. It is thought that it can be further increased.

Example 1 (Effects of various fatty acids on the behavior of Zenkaku no Pecking!1ilI) Using various fats #↓, the effect of stimulating feeding on goldfish was measured by the method described above. That is, a test solution was prepared by dissolving each fatty acid in corn oil to a concentration of 5mM, and this test solution had a concentration of 0.05mM. , test groups T, U, UI
, ■ is cellulose powder, test group V, ■ is cellulose powder and [Swimmy Mini] (trade name, manufactured by Nippon Pet Food ■) are added to 500 mg each of semi-natural feed mixed in 3 to 1 parts, and after mixing, water 0.7 mB was added and combined to prepare bait for the test. In addition, as a control, 0.05 m9 of corn oil and 0.7 m9 water were added to SOO 1 g of feed base material.
A combination feed was also prepared by adding intestinal β. These baits were attached to the string of the above-mentioned device, and the number of goldfish pecks was measured. One test was conducted for each test group, and the same test was repeated five times, and the total number of pecks for the five times is shown in Table 2.

Table 2 Judging from the overall results of test groups 1 to ■ in Table 2, +C
1fi -Coo, C2l) The feed containing C24 saturated fatty acids and/or unsaturated fatty acids causes goldfish to peck at a large number of times, and in particular, the saturated fatty acid Cio, araxic acid, pecks at a large number of times, that is, it has a feeding stimulating effect. It can be seen that the value is high.

Example 2 (Effect of higher saturated fatty acids on pecking behavior of sea bream and yellowtail) The feeding stimulation effects of various higher saturated fatty acids on sea bream and yellowtail were tested using the above method. That is, a test solution was prepared by dissolving each fatty acid in corn oil to a concentration of 5mM, and 0.05m of this test solution was added to "Azicrample" (trade name, Nisshin Feed) for Thailand. For Yellowtail (Yamachi), No. for Buri Mojako, IJ (
The mixture was added to 500 mg of a feed base material (trade name, manufactured by Oriental Yeast Co., Ltd.) and mixed, and then 0.7 e of water was added and kneaded to prepare a test feed. As a control, 0.051g of corn oil was added to 500g of feed base material.
A bait was also prepared by adding and kneading 12 and 0.7 layer β of water.

These baits were attached to the threads of the device, and the number of times they were pecked by sea bream and yellowtail was measured. Each test group was tested once, and the same test was repeated 5 times.
Table 3 shows the total number of pecking times for the five times.

Table 3 From the results in Table 3, it can be seen that araxic acid, which is a saturated fatty acid in CIO, causes a large number of pecks in both sea bream and yellowtail, that is, it has a high feeding stimulating effect.

Example 3 (Effect of C20 unsaturated fatty acids on pecking behavior of goldfish) The feeding stimulating effect of various C20 unsaturated fatty acids on goldfish was measured by the method described above. In other words, a test solution was prepared by dissolving each fatty acid in corn oil to a concentration of 5mM, and this test solution (0.05-ε) was mixed with cellulose powder, 500m of semi-natural bait mixed with 3:l (manufactured by Food)
After adding and mixing the mixture, 0.7-β of water was added and kneaded to prepare a test bait. As a control, feed base material 500B, corn oil 0.05■β and water 0
．． A kneaded bait was also prepared with the addition of 7sI2. These baits were attached to the string of the device described above, and the number of pecks by goldfish was measured. One test was conducted for each test group, and the same test was repeated five times, and the total number of pecks for the five times is shown in Table 4.

Table 4 From the results in Table 4, it is concluded that among the C20 unsaturated fatty acids, eicosatrienoic acid has a particularly high number of pecking and has a high feeding stimulation effect.

That is, when the results of Examples 1 to 3 are combined, the fatty acids that show a good effect on the pecking behavior of goldfish, sea bream, and yellowtail are Cps ) C20 + C22, C24 saturated and/or unsaturated fatty acids, and their In particular, C2
Q saturated and/or unsaturated fatty acids are highly effective, and
Cz. It can be seen that eicosatrienoic acid is particularly effective among the unsaturated fatty acids7. Example 4 (Effect of various concentrations of araxic acid on the pecking behavior of goldfish) We prepared feeds containing various concentrations of araxic acid and examined their effects on the pecking behavior of goldfish. That is, a test solution was prepared by dissolving araxic acid in corn oil at various concentrations, and 0.05 ml of this test solution was prepared.
was added to 5001g of cellulose powder and mixed with 0.7g of water! was added and kneaded to prepare bait for the test. In addition, as a counterfeit, a bait was also prepared by adding and kneading 0.05 sff of corn oil and 07-p of water to 50,011 g of the bait base material. These baits were attached to the string of the device described above, and the number of pecks by goldfish was measured. One test was conducted for each test group, and the same test was repeated five times, and the total number of pecks for the five times is shown in Figure 2.

From the results shown in Figure 2, 1 m of araxic acid was added to corn oil.
Test solution dissolved in M (10-”M) concentration 0.051
Add β to cellulose powder 500+H, mix, water 0
．． It can be seen that the feed mixed with 7■β is the most effective. Therefore, the various feeds in the examples are as follows:
Add araxic acid to corn oil at a concentration slightly higher than 1mM.
That is, a test solution dissolved at a concentration of 5 mM was added to and mixed with the feed base material.

Example 5 (Effect of alexic acid on the growth of sea bream) A test solution was prepared by dissolving alexic acid in corn oil to a concentration of 5 mM, and 0.05 sj2 of this test solution was mixed with "Azicrample" (trade name) After adding and mixing the feed base raw material #450 (manufactured by Nisshin Feed ■) to Jug,
0.7 x 2 of water was added and mixed to prepare a test bait. As a control, 500 mg of feed base material, 0.05 sJ2 of corn oil, and 0.7 garden! A kneaded bait was also prepared with the addition of. 5 of these baits each
Give 0.2 to 4.0 g/1 animal daily to 1 sea bream.
After rearing for two weeks, the rate of increase in body weight was measured.

The results are shown in FIG. 3, where 3A is the weight gain rate of the sea bream fed the feed containing alaxic acid, and 3B is the weight gain rate of the sea bream fed the feed not containing alaxic acid.

From the results shown in Figure 3, it can be seen that feed containing araxic acid promotes the growth of sea bream.

Example 6 (Effect of Araxic Acid on the Growth of Flounder) A feed containing araxic acid and a feed containing no araxic acid, similar to those prepared in Example 5, were fed to 7 flounder at @day. o4~50g/each animal, 1
After rearing for 2 weeks, the rate of increase in body weight was measured.

The results are shown in FIG. 4A is the weight gain rate of flounder fed a feed containing alaxic acid, and 4B is the weight gain rate of flounder fed a feed that does not contain alaxic acid.

From the results shown in FIG. 4, it can be seen that feed containing araxic acid promotes the growth of flounder.

Example 7 (Effects of Araxic Acid and Dimethylpropiotethin on Growth of Goldfish) The following feeds A to F were prepared respectively.

A. Corn oil containing 5mM concentration of araxic acid 0.
05■β and 1mM dimethylpropiotetin solution 0.7■! and 500 m of wheat flour as feed base material.
Feed B mixed with g: 5 m of arachidic acid
Corn oil contained in 1 degree MJ is 0.05mj! Feed C: Mixed with 0.7 mQ of water and 500 mg of wheat flour: 0.05 w, g of corn oil and 0.7 + aI2 of 1 mM dimethylpropiotetin solution were mixed with 500 mg of wheat flour.
Feed D::] -0.05 sI2 of oil and 0.7 mff of water were kneaded together, Feed E was kneaded with 500B of wheat flour, 0.7 all of water, and 500 g of wheat flour. Mixed feed F: Corn oil 0.05■β and water 0.7mm! ``Swimmy Mini'', a natural feed, is used as a feed base material.
(Product Name 1 Made by Nippon Bet Food ■) Mixed using 500g of feed A, 10 animals, B 10 animals, C 9 animals, D food 9 animals, E The feed was given to 10 goldfish and the F feed was given to 9 goldfish at a rate of 0.1 to 2.0 g/fish every day, and the fish were raised for 5 weeks, and the rate of increase in body weight was measured.

The results are shown in FIG. 5, and the weight gain rates of goldfish fed with food A to F are shown as 5A to 5F, respectively.

From the results shown in Figure 5, feed B containing araxic acid,
Feed C containing dimethylpropiotethin has almost the same effect on improving the growth of goldfish, and is close to the effect of natural bait F, but feed A containing both araxic acid and dimethylpropiotethin has almost the same effect on improving the growth of goldfish. , it can be seen that compared to feeds B and C, it synergistically improves the growth of goldfish.

In addition, by comparing feeds with feed F that contain the same corn oil and water but different feed base materials, we found that the natural feed ``Swimmy Mini'' (trade name, manufactured by Nippon Betfood) was more effective than wheat flour. ) clearly increases the growth of goldfish, but feed A, which contains both araxic acid and dimethylpropiotethin, is more effective in growing goldfish than natural feed F, even if the feed base material is flour. It can be seen that it is much higher.

"Effects of the Invention" As explained above, C1, which is the feeding stimulant of the present invention,
-, Cx. , C1M, Cza, and especially C20 saturated and/or unsaturated fatty acids, in very small amounts, promote feeding of seafood and also greatly promote growth. Also, C,,,C,. , c2□, C2
By using the saturated and/or unsaturated fatty acid of No. 4 in combination with dimethylpropiotethin, the effect is synergistically improved.

Sitakach, CIll, C20, Czz, C2
By adding saturated and/or unsaturated fatty acids (4) or dimethylpropiotethine together with various feed base materials, it stimulates the sense of smell and taste of fish and shellfish, making them eat more food. Efficiency can be increased and growth can also be promoted. Also, C+a, C2Q,
Since the optimum effect can be obtained when the amount of Czx, C22 saturated and/or unsaturated fatty acids, or dimethylpropiotetin is around 10-''M, it is thought that the increase in cost due to addition to feed is small. .

That is, the present invention adds C18 and Cz to the live baits and fishmeal-containing feeds that have been used so far. , C22 , C2
Adding saturated and/or unsaturated fatty acids (2) or dimethylpropiotethin together with these fatty acids may be used to further increase the feed efficiency and growth promoting effect, or to further improve part or all of the feed composition that has been used so far. The poor feeding and growth rate of C
, , , C, , , C, □, C24 saturated and/or unsaturated fatty acids, or it can be applied to improve by adding dimethylpropiotethin, and new developments are expected in the aquaculture industry. It is possible.

[Brief explanation of drawings]

FIG. 1 is a schematic explanatory diagram showing the apparatus used in the experiment on the feeding stimulation effect, and FIG. 2 is a chart showing the effects of various concentrations of araxic acid on the pecking behavior of goldfish. Figure 3 is a chart showing the effect of alexic acid on the growth of sea bream, Figure 4 is a chart showing the effect of alexic acid on the growth of flounder, and Figure 5 is a chart showing the effect of alexic acid on the growth of goldfish. This is a chart showing the effect of

Claims (8)

[Claims] (1) C_1_8, C_2_0, C_2_2, C_2_
4. A feeding stimulant for seafood, characterized by comprising at least one selected from 4 saturated and/or unsaturated fatty acids. (2) C_1_8, C_2_0, C_2_2, C_2_
A feeding stimulant for seafood, characterized by comprising a combination of at least one selected from 4 saturated and/or unsaturated fatty acids and dimethylpropiotethine. (3) The substance that stimulates feeding of seafood according to claim 1 or 2, which contains C_2_0 saturated and/or unsaturated fatty acids. (4) Feed base materials for seafood, C_1_8, C_
2_0, C_2_2, and C_2_4 at least one selected from saturated and/or unsaturated fatty acids. (5) Feed base materials for seafood, C_1_8, C_
1. A feed for seafood, comprising at least one selected from saturated and/or unsaturated fatty acids such as 2_0, C_2_2, and C_2_4, and dimethylpropiotethine. (6) The seafood feed according to claim 4 or 5, which contains C_2_0 saturated and/or unsaturated fatty acids. (7) Said C_1_8, C_2_0, C_2_2, C_
The feed for fish and shellfish according to any one of claims 4 to 6, containing at least one selected from 1_4 saturated and/or unsaturated fatty acids at a concentration of 10^-^9 to 1M. (8) 10^-^9~1 of the dimethylpropiotetin
The seafood feed according to any one of claims 5 to 7, containing the feed at a concentration of M.