JP2015167534A - Shellfish floating larva breeding method using lysozyme - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a shellfish floating larva breeding method using lysozyme in which shellfish floating larvae are made to orally take in the lysozyme to promote extinction activities of digestive tract epithelial cells and surrounding tissues, and thereby the uptake of lymphotoxin to the digestive tract epithelial cells and its effect are reduced and the occurrence of failure of digestive tract epithelial cells is prevented, and as a result, a survival rate can be improved while maintaining the growth of the shellfish floating larvae.SOLUTION: A shellfish floating larva breeding method using lysozymes is characterized in that lysozyme is orally supplied to shellfish floating larvae as lysozyme hydrochloride to prevent the occurrence of failure of digestive tract epithelial cells, and thereby a survival rate is improved while maintaining the growth.

Description

  The present invention improves survival in the breeding of shellfish floating larvae that grow by feeding on the floating period of bivalves (oysters, red scallops, snails, clams, clams, etc.) and echinoderms (sea urchins, sea cucumbers). -It relates to a method for raising floating larvae using lysozyme which is effective in reducing drowning.

The floating larvae of bivalves grow into a shell-topped (Ambo-stage) floating larvae that have completed the digestive organs after feeding through the initial D-type stage, and undergo transformation when they grow to a certain size. It becomes the same form as the adult shellfish and shifts from floating life to bottom shark life. Pentachula, a echinodermoid larvae with a similar floating stage, such as sea cucumbers, grows while feeding during the floating larval stage called the auriclariae stage, and lives in the bottom of the body through Dorioralaria larvae, a floating larvae form in the transitional stage. Become a larva and grow into an adult sea cucumber. In the production of shellfish seedlings, the breeding results in the floating larval stage determine the success or failure of the production. In the past breeding of floating shellfish larvae, the microalgae species that serve as food in order to maintain good survival and growth Studies on supplements, nutritional supplements, breeding equipment improvements and breeding water management techniques have been conducted. However, despite these efforts, there are growth stagnation and mass drowning that cannot be explained from the above viewpoint, which hinders stable seedling production.
The inventor conducted a histopathological examination of the unsettled floating larvae. As a result, the intestinal epithelial cell contents (bleb) were confirmed. It suggested the possibility of malfunction of ductal epithelial cells. This disorder is said to occur when cytotoxic factors (such as fine granules having toxicity such as peroxides) are taken into cells as part of digestive activity (Non-patent Document 1). In other words, as a cause of growth stagnation and depletion of unknown cause, it was speculated that digestive and absorptive cells take up some obstacle factors (for example, toxic granules such as peroxides, denatured lipids or protein particles) and lead to dysfunction (non- Patent Document 2).

Yoshiyuki Sugishita, Mizuki Hirano, Mobin, SMA., Kenichi Tsutsumi, Shinya Kanai, Kazuma Yoshikoshi, Kenji Hara (2002) Causes and Causes of Massive Death of Akoyagai Annual Meeting of the Fisheries Society of Japan Satoshi Ohashi, Shunsuke Iwanaga, Shiki Sugihara, Kazuki Matsukura, Toshiyuki Yamada, Hiroshi Tomiba, Hiroshi Niiyama, Kazuma Yoshikoshi (2013) Histological characteristics of floating larvae with poor production in oyster seedling production Spring Meeting of the Japanese Society of Fisheries Science Abstract of the lecture

  However, the obstructive factor is not clear because its composition and shape are unknown and fine (less than 1 micron). Moreover, since the substance has not been identified, the countermeasure is unknown. Therefore, the inventor examined a method for inhibiting the uptake of gastrointestinal epithelial cells that cause damage rather than removing the cytotoxic factor.

  The present invention has been devised in view of the problems as described above, and has been devised to solve the problems. The object of the present invention is to ingest gastrointestinal epithelium by orally ingesting lysozyme into the floating floating larvae. By promoting the anti-inflammatory activity of cells and surrounding tissues, the uptake and influence of cytotoxic factors on gastrointestinal epithelial cells is reduced, and the occurrence of damage to gastrointestinal epithelial cells is suppressed, so that the growth of floating floating larvae It is an object of the present invention to provide a method for raising floating larvae using lysozyme that can improve the survival rate while maintaining the above.

  In order to achieve the above-described problems, a method for raising a carp floating larvae using lysozyme according to the invention of claim 1 provides orally supplying lysozyme as lysozyme hydrochloride to the carp floating larvae, By suppressing the occurrence of failures, the survival rate is improved while maintaining growth.

  Further, as a preferred embodiment of claim 1, a method for raising a shellfish floating larvae using the lysozyme according to the invention of claim 2 provides orally supplying lysozyme as lysozyme hydrochloride to shellfish floating larvae as shellfish floating larvae. In addition, it is characterized by improving the survival rate while maintaining growth by suppressing the occurrence of disorders of the gastrointestinal epithelial cells.

  Further, as a preferred embodiment of claim 1, a method for raising a carp floating larvae using the lysozyme according to the invention of claim 3 provides lysozyme orally as lysozyme hydrochloride to a echinoderm floating larva as a carp floating larva. In addition, the present invention is characterized in that the survival rate is improved while maintaining growth by suppressing the occurrence of damage to the digestive tract epithelial cells.

  Further, as a preferred embodiment of claim 2, a method for raising a shellfish floating larvae using the lysozyme according to the invention of claim 4 is used in a shellfish floating larva as a shellfish floating larvae after the shell top (Ambo) stage larva stage. Lysozyme is supplied orally to floating larvae as lysozyme hydrochloride.

  Further, as a preferred embodiment of claims 1 to 4, the method for raising floating larvae using the lysozyme according to the invention of claim 5 is a breeding method in which an appropriate amount is added to the breeding water as lysozyme hydrochloride. It is characterized by that.

  In addition, as a preferred embodiment of claims 1 to 4, the method for raising a floating larvae using the lysozyme according to the invention of claim 6 is a breeding method in which an appropriate amount is added daily to the breeding water as lysozyme hydrochloride. It is characterized by being.

  Further, as a preferred embodiment of claims 1 to 6, the method for raising a floating larvae using the lysozyme according to the invention of claim 7 uses lysozyme as lysozyme hydrochloride to bring it to a breeding water at a low concentration that does not exert antibacterial action. It is a breeding method to be added.

  In addition, as a preferred embodiment of claims 1 to 7, the method for raising a floating larvae using the lysozyme according to the invention of claim 8 has a low concentration of 0.01 to 0.1 ppm which does not exert an antibacterial effect by using lysozyme as lysozyme hydrochloride. It is a breeding method that is added to the breeding water at a concentration.

  Further, as a preferred embodiment of claim 1, claim 2, and claim 4, a method for raising a shellfish floating larva using the lysozyme according to the invention of claim 9 is a shellfish floating larva as a shellfish floating larva. Breeding method of adding lysozyme to lysozyme orally in floating larvae orally at low concentrations of 0.02 to 0.1ppm that do not exert antibacterial activity, with feed algae daily from the (Ambo) stage larva stage to the bottom stage It is characterized by being.

  In addition, as a preferred embodiment of claims 1 and 3, the method for raising a carp floating larvae using the lysozyme according to the invention of claim 10 is based on a mangrove floating larva as a carp floating larva in the Penticula larvae period after the Auriclariae stage. Until now, it is a breeding method wherein lysozyme is orally added to floating larvae as a lysozyme hydrochloride at a low concentration of 0.02 to 0.1 ppm which does not exert an antibacterial action, daily with feed algae.

  According to the method for rearing a floating larvae using lysozyme according to the invention of claim 1, by promoting the anti-inflammatory activity of gastrointestinal epithelial cells and surrounding tissues by orally ingesting lysozyme into the floating larvae Incorporating cytotoxic factors into gastrointestinal epithelial cells and reducing their effects, and suppressing the occurrence of gastrointestinal epithelial cell damage, can improve the survival rate while maintaining the growth of floating floating larvae it can.

  According to the method for raising a floating shellfish larva using lysozyme according to the inventions of claim 2 and claims 4 to 9, in addition to the effect of claim 1, the shellfish floating larva is It is possible to reduce mass drowning and growth stagnation after the season, to realize growth stagnation and improvement of the bottoming rate, and to improve the number of seedling production.

  According to the method for raising a floating floating larva using the lysozyme according to the inventions of claim 3, claim 5 to claim 8 and claim 10, in addition to the effect of claim 1, the floating floating larva is an echinoderm. For example, manamako floating larvae can improve the transformation rate from the Aurichralia period to the Dorioralian period and the Pentacutula period larvae, and can improve the number of seedling production.

It is a figure which shows the appearance rate of each period larva at the age of 15 of the sea cucumber in Example 1 of this invention. It is a figure which shows the appearance rate of each stage larva at the age 20 of the sea cucumber in Example 1 of this invention. It is a transition figure of the average shell length of the lysozyme administration group (after age 6) and the control group in Example 2 of this invention.

Hereinafter, modes for carrying out the present invention will be described.
In order to use the present invention, as egg white-derived lysozyme hydrochloride, in the case of shellfish floating larvae, from the top of the shell (Ambo) period to the bottoming stage, in the case of sea cucumber floating larvae, from the Auriclaria period to the Pentacutura larval stage, It is added to the breeding water every day together with normal feed algae in the breeding water at a low concentration range of 0.02 to 0.1 ppm. The addition may be once a day. If the concentration is not low, for example, if the concentration exceeds 0.2 ppm, the survival rate decreases.
The method for raising floating shellfish larvae using the lysozyme of the present invention is that lysozyme is added to the breeding water as lysozyme hydrochloride so as to have a low concentration, for example, 0.01 to 0.1 ppm. To reduce the mass drowning and growth stagnation, and improve the growth stagnation and bottoming rate.
The method for raising floating larvae using the lysozyme of the present invention adds lysozyme as lysozyme hydrochloride to the breeding water at a low concentration, for example, 0.01 to 0.1 ppm. The transformation rate from the dairy stage to the Dorioralia stage and the Pentacutura stage larvae is improved, and the seedling production number is improved (Figs. 1 and 2).

In the method for raising floating shellfish larvae using the lysozyme of the present invention of Examples 1 to 2, as a result of comparative tests using shellfish, for example, oysters and echinoderms, for example, shellfish floating larvae, the seedling production success rate It came to find the contents of the effect which improves.
Examples 1 to 2 will be described more specifically below, but the present invention is not limited to the following examples.

[Example 1]
In order to improve seedling production efficiency of floating sea cucumber larvae, the effect of adding egg white-derived lysozyme hydrochloride to the breeding water was investigated.
The experiment was conducted for 20 days from April 9, 2013 to April 29. The breeding density at the start of the experiment was 0.75 individuals / ml, and a 500-liter round aquarium was used as the breeding tank in both the experimental group and the control group. C.calcitrans and C.gracilis were used as food algae. Also, oyster egg grind (10 mg / ml in dry weight) was used as an auxiliary feed. In the experimental group, pulverized egg white lysozyme hydrochloride granules (manufactured by Nichi-Iko Co., Ltd., lysozyme content 10%) were added to the breeding water at a concentration of 0.02, 0.1, 0.2 ppm between the ages of 1 and 20. The control group had the same feed conditions except for the egg white-derived lysozyme hydrochloride granules. C. calcitrans was fed 10,000 to 20,000 cells / ml / day, C. gracilis was fed 20,000 to 50,000 cells / ml / day, and supplementary egg grind was fed 10 mg / ml / day dry weight. . The water temperature was 20.0-22.0 ° C. using a water bath. Half of the water was changed daily by siphon. Dorioralaria larvae emerged from the age of 14 and pentacchuula larvae emerged from the age of 15 and began to settle. For this reason, the experiment was completed by comparing the larval appearance rate of each stage at age 20 days.
In the control plot, the incidence of larvae after the Dorioraria period was 44.5% at age 20, whereas in the experimental plot, it was 61.2%, 82.7%, and 74.0% for the 0.02ppm, 0.1, and 0.2ppm concentrations, respectively. (FIGS. 1 and 2). However, the survival rate was 98 to 100% in the control, 0.02ppm, and 0.1ppm groups at 15 days of age, whereas the survival rate was as low as 68.0% in the 0.2ppm group. Adverse effects such as conspicuous floating larvae with discoloration were observed (Table 1).

[Example 2]
In order to improve the seedling production of floating larvae of oysters, the effect of adding egg white-derived lysozyme hydrochloride to the rearing water after the shell-top larvae was investigated.
The experiment was conducted for 26 days from May 26, 2013 to June 20, 2013. The experiment was preliminarily raised until age 6 and was divided into tanks at the start of the experiment. The breeding density at the start was 2.28 and 2.46 individuals / ml, and a 500-liter round tank was used as the breeding tank in both the experimental group and the control group. C.calcitrans and P.lutheri were used as food algae. Also, oyster egg grind (10 mg / ml in dry weight) was used as an auxiliary feed. In the experimental group, egg white-derived lysozyme hydrochloride granules (manufactured by Nichi-Iko Co., Ltd., lysozyme content 10%) were pulverized and added to breeding water at a concentration of 0.01 ppm after 6 days of age. The control group had the same feed conditions except for the egg white-derived lysozyme hydrochloride granules. C. calcitrans was fed 10,000 to 30,000 cells / ml / day, P. lutheri was fed 2,000 to 4,000 cells / ml / day, and egg broth was fed 10 mg / ml / day dry weight as an auxiliary feed. . The water temperature was 23.2 to 24.9 ° C. using a water bath. Half of the water was changed by siphon every day and the entire amount was changed every 3-5 days. The transition of the average shell length during the experiment period is shown in FIG. 3, and the survival rate at the age of 20, the number of peeled larvae, and the average number of larvae per 100 cm ^{2 of} collector are shown in Table 2.
The average shell length was slightly higher in the experimental group after 14 days of age. The survival rate at 20 days of age was almost doubled at 14.6% in the control group and 29.8% in the experimental group. During the breeding period, sedimentation of floating larvae was often observed in the control plot, but not in the experimental plot. From age 20 onwards, 300 bottom collectors (vinyl chloride 10 cm × 10 cm thickness 0.5 mm) were introduced for seedling, and the seedlings were peeled off at age 54 for comparison. The number of exfoliated individuals was 695 in the control group and 8044 in the experimental group, showing an approximately 11-fold difference. The average shell height was 8.9 mm and 11.7 mm, respectively.

  The present invention can be applied to other shellfish artificial seedlings (oysters, red scallops, clams, clams and pearl oysters) and sea urchins (aconi, purple sea urchins, bahun sea urchins, sea urchin sea urchins, sea urchin sea urchins, sea urchin sea urchins). It is possible to contribute to the aquaculture field (aquaculture and cultivated fisheries) in the fishery industry.

Claims (10)

  Using lysozyme characterized by improving survival rate while maintaining growth by supplying lysozyme as lysozyme hydrochloride to orchid floating larvae orally and suppressing the occurrence of damage to gastrointestinal epithelial cells Chow floating larva rearing method.   It is characterized by improving survival rate while maintaining growth by supplying lysozyme as lysozyme hydrochloride orally to shellfish floating larvae as shellfish floating larvae and suppressing the occurrence of damage to gastrointestinal epithelial cells A method for breeding a carp floating larva using the lysozyme according to claim 1.   It is characterized by improving the survival rate while maintaining the growth by supplying lysozyme as lysozyme hydrochloride orally to floating larvae of echinoderms as floating larvae and suppressing the occurrence of gastrointestinal epithelial cell damage. A method for breeding a carp floating larva using the lysozyme according to claim 1.   The lysozyme according to claim 2, wherein lysozyme is supplied to the floating larvae orally as lysozyme hydrochloride in the shellfish floating larvae as the shellfish floating larvae after the top larvae period. Chow floating larva rearing method.   The method for rearing a floating floating larva using a lysozyme according to any one of claims 1 to 4, wherein the lysozyme is lysozyme hydrochloride and an appropriate amount is added to the breeding water.   5. A method for raising floating floating larvae using lysozyme according to any one of claims 1 to 4, which is a breeding method in which an appropriate amount of lysozyme as lysozyme hydrochloride is added to the breeding water every day.   The method of raising larvae using lysozyme according to any one of claims 1 to 6, wherein the lysozyme is lysozyme hydrochloride and added to the breeding water at a low concentration that does not exert antibacterial action. Method.   The lysozyme according to any one of claims 1 to 7, wherein the lysozyme is added as a lysozyme hydrochloride to the breeding water at a low concentration of 0.01 to 0.1 ppm which does not exert an antibacterial action. Chow floating larva rearing method.   In shellfish floating larvae as shellfish floating larvae, lysozyme is orally administered to floating larvae as lysozyme hydrochloride from the shell-top larva stage to the bottoming stage, and a low concentration of 0.02 to 0.1 ppm that does not exert antibacterial action 5. A method for raising floating floating larvae using lysozyme according to any one of claims 1, 2 and 4, wherein the method is a method of breeding which is added to the breeding water every day together with feed algae.   In manamako floating larvae as mosquitoes floating larvae, lysozyme is orally administered to floating larvae as lysozyme hydrochloride from the Aurichrala period to the Pentacutula larvae stage, daily in the breeding water at a low concentration of 0.02 to 0.1 ppm that does not exert antibacterial action, 4. A method for raising floating floating larvae using lysozyme according to claim 1 or 3, wherein the method is a breeding method to be added together with feed algae.

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