JP2005270101A - Feed for eel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain feed for eel excellent in shape retention in water and feeding properties while containing medium chain fatty acid having an anti-parasitic action. <P>SOLUTION: The feed for eel includes C6-12 medium chain fatty acid in eel feed in the form of its salt, ester or their emulsion form. The feed for eel is added with for instance, 0.5-5 wt.% per the dry weight of for instance, at least one kind selected from caprylic acid, pelargonic acid, capric acid and lauric acid as C6-12 medium chain fatty acid, as for instance, calcium salt, sodium salt, potassium salt and magnesium salt, or as monoglyceride, diglyceride, and triglyceride, or as their emulsion. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an eel feed that is excellent in water retention and has good food intake while containing a medium chain fatty acid having an antiparasitic effect.

  In aquaculture, fish disease is a very big problem because it hinders stable production. The inventors previously found that a fatty acid having 6 to 12 carbon atoms is effective for parasitic diseases of fish, and applied for a patent and registered (Patent Document 1). Patent Document 2 describes a feed for fish farming characterized by containing as an active ingredient at least one selected from medium chain fatty acids having 6 to 12 carbon atoms or salts thereof, monoglycerides and diglycerides of the fatty acids. And are described as being effective against bacterial infections.

  In eel farming, a so-called “mixed feed” is used, which is made by adding an appropriate amount of pregelatinized starch as a binder to fish meal, etc. that has been dried and powdered from walleye pollock, sardine, etc., and kneaded with water. Has been. Noodles are submerged in water and given to eels. Eat eels with their heads thrust into them. Therefore, the physical property which does not melt | dissolve in water or a collapse | crumble is required, and the thing with the favorable feeding property which suited the taste of the eel is desired.

Japanese Patent No. 3480566 JP-A-4-158750

  The inventors have found that when medium chain fatty acids are added, there is a problem in the shape retention of the eel paste. It is an object of the present invention to provide an eel feed having physical properties and feedability suitable as an eel feed and having an antiparasitic effect.

The gist of the present invention is an eel feed containing a medium chain fatty acid having 6 to 12 carbon atoms in the form of a salt or ester thereof or an emulsion thereof, which is excellent in shape retention under water and has a good food intake. To do.
The present invention also includes an anti-parasitic disease that contains a medium chain fatty acid having 6 to 12 carbon atoms in the form of a salt or ester thereof or an emulsion thereof, has excellent shape retention in water, and has good feeding properties. An eel feed having an action is summarized.
In the present invention, the medium chain fatty acid having 6 to 12 carbon atoms preferably contains one or more of caprylic acid, pelargonic acid, capric acid and lauric acid. The salt of the medium chain fatty acid is preferably a calcium salt, a sodium salt, a potassium salt, or a magnesium salt. The ester of the medium chain fatty acid is preferably a single chain fatty acid monoglyceride, diglyceride or triglyceride, or a mixture of two or more. The emulsion is preferably an O / W type emulsion. The shape retention in water is that of an eel feed with no medium chain fatty acid added, that is, the shape is maintained for more than 1 hour after being immersed in still water. The medium chain fatty acid having 6 to 12 carbon atoms is preferably contained in an amount of 0.5 to 5% based on the dry weight of the paste. The present invention is particularly effective in an eel feed that is a kneaded bait.

  By using medium chain fatty acid as calcium, potassium, sodium salt, monoglyceride, diglyceride, triglyceride, or as an emulsion of these, anti-parasitic properties can be obtained without adversely affecting the physical properties and feeding properties of eel feed. Medium chain fatty acids having helminthic action can be added.

The medium chain fatty acid having 6 to 12 carbon atoms used in the present invention contains one or more of caprylic acid, pelargonic acid, capric acid and lauric acid. preferable.
The salt of the medium chain fatty acid used in the present invention is preferably a calcium salt, a sodium salt or a potassium salt.
The ester of the medium chain fatty acid used in the present invention is preferably one kind or a mixture of two or more kinds of monoglyceride, diglyceride and triglyceride of the medium chain fatty acid. In diglycerides and triglycerides, not all fatty acids need be medium chain fatty acids, and the amount added to the feed may be adjusted depending on the content of medium chain fatty acids.

The emulsion used in the present invention is preferably an O / W type emulsion, but can also be used in a W / O type. The emulsifier can be used as long as it is permitted to be used for feed or food. Examples of the emulsifier include glycerin fatty acid ester, sucrose fatty acid ester, sorbitan fatty acid ester, polyethylene sorbitan fatty acid ester, propylene glycol fatty acid. Examples include ester, egg yolk, lecithin, soybean phospholipid, gum arabic, alginic acid, gelatin and the like. Stirring and emulsification may be performed batchwise or continuously. When stirring and emulsifying, it is usually used to prepare an emulsion of fats and oils, such as an impeller type mixer, a whipper type mixer, a wire type mixer, a turbine type mixer, a disk blender, a homogenizer, a colloid mill, etc. be able to. This stirring and emulsification is usually performed at about 5 to 35 ° C., and the emulsification is not smoothly performed even if the temperature is too low or too high. When the fats and oils have a high melting point, it may be carried out while heating a little.
In the present invention, being excellent in water shape retention means that it is practical as an eel feed. Specifically, it is a degree that keeps the form for more than 1 hour after being immersed in still water, and when fed to an eel, it is less dispersed even by the feeding behavior of the eel, and it is a normal eel with no medium chain fatty acid added It has the same physical properties as food.

The good feeding ability means that it has the same feeding ability as that of a normal eel feed to which no medium chain fatty acid is added.
The medium-chain fatty acid of the present invention has a preventive / therapeutic effect such as Pseudodactyrogillus vinii, Pseudodactyrogillus angire, white spotworm, Trichodina, etc., which parasitize eels, that is, an antiparasitic effect. In order to exert an antiparasitic effect, it is preferable to continuously administer 100 to 600 mg, preferably 400 mg or more per kg of fish body weight during the breeding period. The medium chain fatty acid having 6 to 12 carbon atoms is preferably contained in an amount of 0.5 to 5% based on the dry weight of the paste. Antiparasitic action is exhibited even when added to feed in the form of salt, monoglyceride, diglyceride, triglyceride or emulsion. It is most effective to add it as an emulsion.

Any eel feed can be used as long as it is a commercially available shark feed, and the components of the present invention can be added regardless of natural feed or artificial feed. For example, as the artificial blended feed, animal ingredients such as fish meal, vegetable oil ingredients such as soybean oil meal, and grain ingredients such as wheat flour are appropriately blended and shaped. The method for adding to feed is not particularly limited, and it may be mixed with feed raw material or suspended in water or feed oil. Addition to the feed can be added in any process, for example, in the case of eel paste, fish meal is the main ingredient, starch, defatted soybeans, vitamins, minerals are blended and crushed, Since fish oil and water are added to the eel when it is fed to form a paste bait, it may be added at the time of blending, or may be added together with the addition of fish oil and water.
In order to feed the eel paste of the present invention and culture the eel, the culture method may be a conventional culture method. In order to exert the effect of the present invention, the eel kneading of the present invention is performed. It is desirable to continue feeding during the breeding period.

In general, the eel feed of the present invention is based on fish and shellfish powder, and in order to improve the cohesion when the feed is kneaded with it, an adhesive, and if necessary, amino acids and salts thereof, Contains nutrients such as vitamins and minerals, ingredients such as surfactants and spices.
As the seafood powder that forms the base material of the eel paste of the present invention, any of the seafood powders conventionally used as eel feed can be used, for example, walleye pollack, squid, flatfish, sardine, mackerel, Mention may be made of fish meal made from seafood such as herring, saury, hockey, hoki, hake, clams and oysters. The eel feed of the present invention may contain only one kind of the above-described seafood powder, or may contain two or more kinds of fish meal. It is preferable to mix and use a plurality of fish meals from the viewpoints of palatability and economical efficiency of eels. The content of seafood powder can vary depending on the type of seafood powder, the age of the eel, etc., but in terms of nutritional value, economy, caking properties, etc., the eel feed of the present invention is generally Based on the total mass of the eel feed, it is preferable to contain the seafood powder at a rate of 60 to 75% by mass, and more preferably at a rate of 65 to 70% by mass.
Examples of the above-mentioned pressure-sensitive adhesive for improving the unity of the eel paste of the present invention include, for example, pregelatinized starch such as pregelatinized potato starch and pregelatinized tapioca starch, sodium polyacrylate, guar gum, sodium alginate, xanthan gum, Examples thereof include carboxymethylcellulose and gluten. In the eel feed of the present invention, one or more of the aforementioned adhesives can be used. Among them, α-starch such as pregelatinized potato starch and pregelatinized tapioca starch is preferably used as the pressure-sensitive adhesive from the viewpoint of caking property and cost.
When adding liquid such as water and oil to powdered eel feed to make a kneaded feed, 100 to 200 water and 0 to 15 oil are added to the eel feed powder 100 and kneaded. It is preferable from the viewpoints of handling of food, ease of feeding, feeding, nutrition, and the like.

  Examples of the present invention will be described below, but the present invention is not limited thereto.

<Comparison of physical properties>
Commercial eel feed (manufactured by Nippon Compound Feed Co., Ltd., trade name: Markin, crude protein 48% or more, crude fat 4% or more, crude fiber 1% or less, crude ash 15% or less, calcium 2.3% or more, phosphorus 1.5% or more ) Free octanoic acid (C8) (manufactured by Wako Pure Chemical Industries, Ltd., octanoic acid (n-caprylic acid), special grade) or calcium octoate (C8Ca) (manufactured by Sakai Chemical Industry Co., Ltd.) as 2 wt. % And 150% by weight of water was added to prepare a paste (Table 1). Put this kneaded bait into a basket (W35cm x L25cm x H8cm, 84cm 0.6cm x 5cm slits on the bottom and 66 on the side), and then add this kneaded bait to the aluminum Housed in bread-making bread (W40cm × L60cm × H5cm), 1L of tap water was poured every minute to confirm the degree of collapse. As shown in FIG. 1, the feed added with calcium octoate does not collapse even after 2 hours and maintains the original state, whereas the feed added with octanoic acid is immediately after being put in water. It begins to collapse and after 1 hour a considerable amount of feed has collapsed and has flowed out of the basket, leaving only a few remaining after 2 hours.
After standing for 2 hours, the weight was measured. As a result, in C8 addition section, it was 59.8% compared with the beginning, and about 40% was flowing out. On the other hand, in the C8Ca-added section, it was 108.8% compared to the start time, and there was no outflow even when it looked.

<Antiparasitic effect and feed efficiency>
Test area:
Free octanoic acid group, calcium octanoate (Ca octanoate) group, octanoic acid triglyceride (octanoic acid TG) group (trade name; Cocoonado RK, caprylic acid triglyceride, appearance and properties (slightly yellow transparent liquid), acid Value (0.3 or less), saponification value (345 to 365), iodine value (4 or less)) and octanoic acid triglyceride emulsion (octanoic acid TG emulsion) group, and control group with no octanoic acid added as a control group Was provided.
The octanoic acid TG emulsion used in this example was mixed with 45% octanoic acid triglyceride, 2% emulsifier (M-7D, polyglycerin fatty acid ester: myristic acid: manufactured by Mitsubishi Chemical Foods), 53% water, Pre-emulsification with TK homomixer (manufactured by Tokushu Kika Co., Ltd.) at 7,000-12,000 rpm for 2-5 minutes at ℃, followed by main emulsification at 400-800 kg / cm ² with high-pressure homogenizer (manufactured by APV). Immediately after emulsification with a homogenizer, the temperature was reduced to 10 ° C. or less.
Test method: Preliminary breeding: Breeding water was placed in 10 0.7tFRP water tanks to a volume of about 315L each, and a total of 65 European eels were accommodated in each tank (European weight average 9.3g on July 8) 30 eels were accommodated in each ward, and 35 eels were accommodated on the 12th). Water injection volume is 7L / min, breeding water temperature is 24 ℃. Feeding was carried out once a day, and eel feed (powdered feed) was fed at a dry matter weight of 2-3% per fish weight. From July 18, octanoic acid and octanoic acid-related substances corresponding to the test plot were added to the feed in the same manner as in Example 1 and fed. In addition, octanoic acid and octanoic acid-related substances were added every 2 days so that their concentrations gradually increased to 0.5%, 1.0%, 1.5% and 2.0%, and pre-bred for about 1 month.
Measurement before the start of the test: Five fish were sampled from each test area, and the body weight, body length, and number of infestations were measured. No parasitic infection was observed before the start of the challenge test (Table 2).

Attack test: On August 13, 10 infection sources (large European eels infected with Pseudodactylgillus) were placed in tubes and placed in each tank, and a parasite attack test was started. In addition, when we confirmed in the morning on the 14th, there were those that were drowned in the source of infection, so the number of infection sources was 8 in each ward, the infection source was removed at 14:00 on 15th two days later, and the attack was terminated It was.
Prior to the attack test, 10 large European eels infected with Pseudodactylgillus used as the source of infection were sampled and the total number of pupae was removed and the number of infestations counted. These 10 eels weighed 80.0 ± 8.8 g (mean value ± standard deviation), had a total length of 35.4 ± 1.3 cm, and had 2536 ± 2345 infestations.

  On the 10th and 32nd days after the attack test, the animals were reared for 62 days while measuring the number of parasites in each group, and finally, the number of parasites, survival rate and growth were measured. In the final measurement, select 10 large eels remaining in each test area, count Pseudodactylgillus parasitizing for all pupae, and measure the weight of all individuals remaining in the aquarium (Table 3).

As a result, the test group to which octanoic acid and related substances were administered tended to have fewer parasitics than the control group. In particular, the octanoic acid Ca and octanoic acid TG emulsion had low values. Moreover, when the number of parasitism per phlegm and phlegm valve was confirmed, the same tendency was shown (FIG. 3).
Furthermore, when the feed efficiency and the survival rate were compared, the feed efficiency and the survival rate were the same as those in the control group except for the free octanoic acid group (Table 4).

  From the above, when free octanoic acid was added to the eel feed, the tackiness was lost and the physical properties could not be maintained. However, there was no problem in the physical properties of calcium octoate, triglycerides and their emulsions. The feed efficiency of the free octanoic acid-added feed was remarkably poor compared to other test plots. This is due to the fact that the eel does not actually eat because the feed collapses (and after the feed, the remaining food is collected after a certain period of time, and is recovered as the remaining food from the weight of the first feed. It is thought that this is due to the fact that the food intake was actually low due to the problem of palatability. In addition to the antiparasitic effect, the octanoic acid TG emulsion group showed a tendency toward good feed efficiency, and it was thought that adding octanoic acid as an emulsion had a good effect on these.

<Examination of types of medium chain fatty acids>
Various free medium chain fatty acids or triglycerides were added to prepare trial foods, and physical properties were examined and an elution test was conducted in the same manner as in Example 1 for 2 hours in running water.
The medium chain fatty acids and triglycerides used in the test are as follows.
C6 (Wako Pure Chemical Industries, Hexanoic acid (n-caproic acid), Wako grade 1 (90% or more))
C7 (Wako Pure Chemical Industries, heptanoic acid (n-heptanoic acid), Wako special grade (98% or more))
C9 (manufactured by Wako Pure Chemical Industries, Nonanoic acid (n-nonanoic acid), Wako grade 1 (90% or more))
C10 (manufactured by Wako Pure Chemical Industries, Ltd., decanoic acid (n-capric acid), Wako grade 1 (not shown))
C12 (Wako Pure Chemical Industries, Lauric acid (dodecanoic acid), Wako special grade (99% or more))
C14 (Wako Pure Chemical Industries, myristic acid, Wako special grade (98% or more))
C16 (Wako Pure Chemical Industries, palmitic acid, Wako special grade (95% or more))
Triglyceride containing C8, C10, C12 (Coconard ML, manufactured by Kao Corporation, appearance and properties (slightly yellow transparent liquid), acid value (0.1 or less), saponification value (295-325))
Triglycerides containing C8 and C10 (Coconard MT, manufactured by Kao Corporation, appearance and properties (slightly yellow transparent liquid), acid value (0.1 or less), saponification value (340 to 360), iodine value (1 or less))
Then, 2% per dry matter weight was added to each paste. In addition, 150% by weight of water was added to the raw material in the paste. Specifically, in the same manner as in Example 1, the raw material for kneaded baits was 50 g + each fatty acid or TG1 g + 75 g water.

Results: The following shows the properties of the kneaded bait added with each free medium chain fatty acid or triglyceride. Moreover, the residual rate after standing in water for 2 hours is shown in FIG.
C6: Good physical properties that are very close to normal products (kneaded bait without added medium-chain fatty acids, etc.), but it is difficult to use in practice because of the smell.
C7: There is a feeling of looseness compared to normal products. But not as much as C8. The smell is worrisome.
C9: There is a feeling of looseness compared to normal products. Feels close to C8.
C10: Fatty acids become solid from C10. The part where the added C10 is granulated is in a state where the kneaded bait is peeled off, but the overall physical properties are close to normal products.
C12: Almost the same as C10.
C14: The part where C14 is granulated does not peel from the kneaded bait compared to C10 or C12. Physical properties are almost the same as normal products.
C16: Same as C14.
Triglycerides containing C8, C10, C12: Same as normal products.
Triglycerides containing C8 and C10: Same as normal products.

  The results of the dissolution test are as shown in FIG. 4, and it was found that the deterioration of the physical properties of the paste is a phenomenon peculiar to fatty acids having 8 and 9 carbon atoms.

In order to confirm the feedability of the feed of the present invention, the same four types of feed as in Example 2 were grown on eels grown on a control feed without added octanoic acid for about 4 months and grown to an average weight of about 120 g. Was fed. In Example 2, pre-breeding with an octanoic acid-added feed was carried out from the initial stage, so no problem was observed in feeding. However, in eels that grew to some extent after becoming a control feed, free octanoic acid-added feed was avoided. However, the calcium octoate-added feed came to the kneaded bait and tried to eat it, but immediately stopped eating. The feed supplemented with octanoic acid triglyceride and the octanoic acid triglyceride emulsion had no problem with the feedability as the control diet.
Calcium octoate-added feed can be fed if it is used as a feed from the beginning or if an acclimatization period is provided, but those added as triglycerides or triglyceride emulsions are not necessary, It was shown to have the same feeding ability as feed.

  EFFECT OF THE INVENTION According to the present invention, it becomes possible to provide a eel paste that has physical properties and feeding properties suitable as an eel paste, and has an antiparasitic action. By giving this paste, eel aquaculture It becomes possible to prevent and treat parasitic diseases that are serious problems in Japan. In addition, since the added medium chain fatty acid does not adversely affect the physical properties of the kneaded bait, the kneaded bait disintegrates in water and water contamination is reduced.

It is a photograph which shows the time-dependent change of the shape retention in water of the paste which added the calcium octoate of Example 1, and the paste which added octanoic acid. It is drawing which shows the residual rate after 2 hours at the time of leaving the paste which added the calcium octoate of Example 1 and the paste which added the octanoic acid to water. It is drawing which shows the parasitism number of the parasite per the salmon of a fish fed with the various octanoic acid preparations of Example 2, or a gill valve. It is drawing which shows the residual rate at the time of leaving to stand in the water of the feed which added various medium chain fatty acid of Example 3 for 2 hours.

Claims (9)

  An eel feed containing a medium chain fatty acid having 6 to 12 carbon atoms in the form of a salt or ester thereof or an emulsion thereof, having excellent shape retention in water and good food intake.   An eel having an anti-parasitic activity, having a medium chain fatty acid having 6 to 12 carbon atoms in the form of a salt or ester thereof or an emulsion thereof, excellent in shape retention in water and excellent in food intake feed.   The eel feed according to claim 1, wherein the medium chain fatty acid having 6 to 12 carbon atoms contains one or more of caprylic acid, pelargonic acid, capric acid and lauric acid.   The eel feed according to claim 1, wherein the salt is any one of calcium salt, sodium salt and potassium salt.   The eel feed according to claim 1, wherein the ester is any one of monoglyceride, diglyceride and triglyceride or a mixture of two or more thereof.   The feed for eels of Claim 1 whose emulsion is an O / W type emulsion.   The eel feed according to claim 1, wherein the shape retention in water is such that the shape is maintained for 1 hour or more after being immersed in still water.   The eel feed according to claim 1, comprising 0.5 to 5% of medium chain fatty acid having 6 to 12 carbon atoms per dry weight of the feed. The eel feed according to any one of claims 1 to 8, wherein the eel feed is a paste feed.