JP2000245358A - Production diet and raising method for salmon and/or trout - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the immunological function of salmons and/or trouts and to lower their rate of falling dead by solving problems that their weight increase cannot be expected and other labor than ordinary is required for each work because an intake of diet by them is not enough, the feeding of diet cannot be conducted for the period of medication and the environment is changed with the transfer of a pond, or the like, when measures such as the isolation of infected fish, the disinfection of an infected pond and the medication with medicine (e.g. an antibiotic, or the like) are taken against diseases in raising salmons and/or trouts. SOLUTION: This raising method is to add yeast highly containing glutathione to a production diet for salmons and/or trouts. The quantity consumed of the yeast is arbitrary but is 0.05-5.0 g/day/fish weight (kg), preferably 0.10-1.0 g/day/ fish weight (kg) both in terms of dry weight when being fed. The quantity, the number of times and the period of time of feeding the yeast are accordingly adjusted to the state of fish and an aim.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a feed for cultivating salmon and trout containing a glutathione-rich yeast and a method for cultivating salmon and trout to which a glutathione-rich yeast is administered.

[0002] Salmon and trout, including rainbow trout and Atlantic salmon, are widely used as foodstuffs in countries around the world. In addition, since it is popular as a target fish for fishing, there is a great demand and aquaculture is also actively conducted. Salmon and trout production in 1994 was 797,000 tonnes worldwide. Salmon and trout cultivation started about 20 years ago in Japan,
In 1996, more than 36,000 tons were produced. In Japan, it is produced not only for general consumption but also for stocking and fishing.

[0003]

2. Description of the Related Art Salmon and trout are cultivated actively in Norway, the United Kingdom, Chile, etc., and although cultivation in Japan is still young, it has already been carried out overseas. The most common aquaculture methods are well established. However, measures against diseases caused by viruses, bacteria, parasites and the like have not been thoroughly taken.

As measures against these diseases, methods such as isolation of infected fish, disinfection of infected ponds, and administration of drugs (antibiotics, etc.) have been adopted. Because of this, some deaths are inevitable, and even if they do not die, weight gain cannot be expected due to poor feeding, inability to feed during the drug administration period, changes in the environment due to pond movement, etc. Has problems. In addition, there is a problem in that each work requires manual labor separately from daily work.

[0004]

Means for Solving the Problems The present inventors have conducted intensive studies to solve the above problems, and as a result, the administration of a glutathione-rich yeast improved the immune function as compared with the case where no yeast was administered. The present inventors have found that the mortality rate decreases, and have completed the present invention. That is, the present invention
Culture feed for salmon and trout containing glutathione-rich yeast and salmon / glutathione-rich yeast-administered salmon
A method for cultivating trout is provided.

In the present invention, a glutathione-rich yeast is used. Glutathione alone does not clearly show an improvement in immune function, and in yeasts that do not contain glutathione or have a low glutathione content, unless immunostimulants such as glucan or glucomannan contained in the cell wall are extracted and used, immunity is improved. No improvement in functionality is expected.
The origin of the glutathione-rich yeast used in the present invention is not particularly limited, and baker's yeast, beer yeast, torula yeast, and the like can be used.

The amount of the glutathione-rich yeast used in the present invention is optional, but the amount of yeast at the time of administration may be 0.05-5. 0 g, preferably 0.10 to 1.0 g
The dosage, number of administrations, and administration period are adjusted according to the condition, season, and purpose of the fish. For example, in the case of daily administration, the dosage is 0.10 to 0.30 g per kg of fish body weight, and the dose is administered every time the fish is fed. For example, it is set to 0 g and continuously administered 5 times.

[0007] As a method of administration, glutathione-rich yeast is added to fish meat such as sardine, mackerel, saury, etc. together with a mixed feed, and mixed moist pellets are administered; glutathione-rich yeast is entangled with live feed; Examples include a method of administering a dry pellet containing a glutathione-rich yeast, a method of adsorbing a glutathione-rich yeast on a dry pellet, and the like. The dry pellets can be produced by mixing a glutathione-rich yeast with fishmeal or a commercial compound feed and using a disk pelletizer, extruder or the like. When a solvent is used as the binder, it is desirable to use water, alcohol, or the like.

[0008]

The present invention will be described in more detail with reference to the following examples. Example 1 A rainbow trout breeding test was performed as follows. Average weight about 3
Using 5 g of rainbow trout, 100 fish in each of the test group and the control group were bred in a 1.6-ton onshore concrete tank. The water exchange rate was set at 7 t / day, and aeration was performed by putting air stones into each water tank. Feeding in the morning
Twice a day in the evening, a dry pellet mainly composed of fish meal was administered in an amount of 2% of the fish body weight per day. In the test group, glutathione-rich yeast (trade name: Yeast MG, manufactured by Kojin) was 0.2%.
Dry pellets were added to give g / kg fish body weight / day. After administration for 2 months, 10 fish were sampled from each of the test group and the control group, and the lysozyme activity (lytic activity) of serum, kidney and body surface mucus was measured as an index of immune activity. During the test period, dead fish were immediately taken out and the number of fish was recorded.

A method for measuring lysozyme activity is described below.
The serum was diluted with 10 mM phosphate buffer (hereinafter abbreviated as PB) at pH 7.0. Kidney and body surface mucus were homogenized by adding PB, and the supernatant was diluted with PB for measurement. Micrococcus lysodeikt
After preparing the dried cells of icus with PB so that the absorbance at 530 nm (hereinafter abbreviated as OD ₅₃₀ ) becomes 0.5, the serum, kidney or body surface mucus diluent 1.
0 ml was mixed and incubated at 37 ° C., and lysozyme activity was determined from OD ₅₃₀ before and after the reaction. Table 1 shows the results
Shown in

[0010]

[Table 1]

[0011] As a result of the test, the glutathione-rich yeast was administered to the glutathione-rich yeast-administered group, since the lysozyme activity of the serum, kidney and body surface mucus was higher and the number of dead tails was smaller than that of the control group. It was found that the immune function was improved, and the mortality was reduced.

[0012]

As described above in detail, the feed and the method for cultivating salmon and trout of the present invention have an effect of improving the immune function of salmon and trout, and show a remarkable decrease in the mortality during culturing. Was.

Claims (2)

[Claims] 1. A feed for cultivating salmon and trout, comprising adding yeast containing 0.5% or more of glutathione. 2. A method for cultivating salmon and trout comprising administering a yeast containing 0.5% or more of glutathione.