Method for improving hypoxia tolerance of pinctada martensii

Abstract

The invention relates to the technical field of shellfish culture, in particular to a method for improving hypoxia tolerance of pinctada martensii. Appropriate pinctada martensii is selected for hypoxia training, and then pinctada martensii with mature gonad after hypoxia training is selected as parent pinctada martensii to cultivate seedlings; extracting a nutrient solution from the pinctada martensii subjected to hypoxia training; in the seedling raising stage, a nutrient solution is fed to carry out nutrient enrichment cultivation on pinctada martensii larvae and juvenile mollusks, and the nutrient solution is added in unicellular algae culture to strengthen algae nutrition. According to the method provided by the invention, the physique of the pinctada martensii can be enhanced, a protection effect on body tissues is achieved, the stress reaction of the pinctada martensii to hypoxia is reduced, and the long-term hypoxia tolerance of the pinctada martensii can be remarkably improved.

Description

Technical Field

[0001] The invention relates to the technical field of shellfish culture, and in particular to a method for improving the hypoxia tolerance of Pinctada martensii. Background Art

[0002] Pinctada martensii is the main pearl oyster for cultivating seawater pearls, and its pearl production accounts for more than 95% of seawater pearl production. In recent years, under the influence of natural wind, tides, water temperature, seasonal changes and high-density aquaculture, the Liusha Bay in Leizhou, the main production area of ​​seawater pearl aquaculture in my country, has frequently experienced periodic and continuous hypoxia, which has induced large-scale deaths of Pinctada martensii, seriously restricting the healthy and sustainable development of the seawater pearl aquaculture industry. Hypoxia stress has become one of the key issues facing the seawater pearl industry, and the situation has become more serious in the context of global warming.

[0003] Therefore, cultivating and promoting the cultivation of Pinctada martensii with strong hypoxia tolerance will help improve the survival rate of Pinctada martensii, thereby improving the economic benefits of pearl cultivation and promoting the sustainable development of the pearl industry. Currently, there is no method for improving the hypoxia tolerance of Pinctada martensii. Summary of the invention

[0004] In order to solve the above problems, the present invention provides a method for improving the hypoxia tolerance of Pinctada martensii. The method provided by the present invention can significantly improve the long-term hypoxia tolerance of Pinctada martensii.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] The present invention provides a method for improving the hypoxia tolerance of Pinctada martensii, comprising the following steps:

[0007] 1) After 1.5-2 years old Pinctada martensii are subjected to hypoxia training, they are fattened in natural sea areas to obtain Pinctada martensii oysters with mature gonads;

[0008] 2) breeding the Pinctada martensii with mature gonads to obtain Pinctada martensii seedlings with a shell height of 2 to 4 mm; the breeding method comprises: feeding unicellular algae every day from the D-shaped larvae to the larval attachment stage, and feeding a nutrient solution every 3 days; the unicellular algae are cultivated in a culture solution containing the nutrient solution;

[0009] The preparation method of the nutrient solution comprises: opening the shells of some of the Pinctada martensii oysters with mature gonads that have undergone hypoxia training, collecting shellfish meat and mucus that flows out; mixing the shellfish meat with sterilized seawater, blending the mixture, and filtering to obtain a supernatant; and mixing the mucus with the supernatant to obtain the nutrient solution;

[0010] 3) moving the Pinctada martensii seedlings to a sea area for cultivation, and subjecting the Pinctada martensii seedlings to hypoxia training when they grow to a shell height of 2 to 3 cm, thereby obtaining Pinctada martensii with improved hypoxia tolerance;

[0011] The hypoxia training comprises: subjecting the Pinctada martensii or Pinctada martensii seedlings to hypoxia treatment and recovery treatment in aquaculture seawater in sequence, repeating the hypoxia treatment and recovery treatment 6 to 8 times in total; during the hypoxia treatment, the dissolved oxygen of the aquaculture seawater is 1.5 to 2.0 mg / L, and the time of each hypoxia treatment is 20 to 24 hours; during the recovery treatment, the dissolved oxygen of the aquaculture seawater is ≥6.0 mg / L, and the time of each recovery treatment is 45 to 48 hours.

[0012] Preferably, based on the volume of the larval culture solution, the amount of the nutrient solution fed each time is 15 to 20 ml / L of the larval culture solution.

[0013] Preferably, the method for controlling the dissolved oxygen of the aquaculture seawater during the hypoxia treatment comprises: introducing nitrogen and air into the aquaculture seawater, and controlling the dissolved oxygen content of the aquaculture seawater by adjusting the intake amounts of nitrogen and air.

[0014] Preferably, the unicellular algae include one or more of Isochrysis zhanjiangensis, Isochrysis galbana, Platymonas subcordiformis and Dunaliella.

[0015] Preferably, the culture solution for cultivating the unicellular algae includes a basic culture solution and the nutrient solution; the volume ratio of the basic culture solution to the nutrient solution is 100:0.1-0.3.

[0016] Preferably, the basal culture medium includes Zhanshui No. 107-18 culture medium.

[0017] Preferably, the mass ratio of the shellfish meat to sterilized seawater is 1:3-4.

[0018] Preferably, the method for preparing the sterilized seawater comprises: filtering natural seawater through a sand filter and a ceramic filter element, and then sterilizing the natural seawater to obtain the sterilized seawater; the sterilization method comprises one or more of ultraviolet irradiation, ozone treatment and high temperature boiling.

[0019] Preferably, the shellfish meat is shellfish meat with the adductor muscle removed and the soft part left.

[0020] Preferably, the shell height of the Pinctada martensii with improved hypoxia tolerance is 5 to 7 cm.

[0021] Beneficial effects:

[0022] The invention carries out hypoxia training and recovery treatment in the cultivation stage of Pinctada fuscata; in the seed production stage of Pinctada fuscata, nutrient solution is fed to Pinctada fuscata larvae and juvenile spats formed after the larvae attach and metamorphose, so as to carry out nutritional fortification cultivation of the larvae and juvenile spats; and nutritional fortification is carried out on unicellular algae fed to the Pinctada fuscata larvae and juvenile spats, so as to further improve the hypoxia tolerance of the Pinctada fuscata through food fortification.

[0023] Since the nutrient solution is composed of the mucus and soft part extract of the Pinctada martensii with strong hypoxia tolerance, it contains rich amino acids, highly unsaturated fatty acids, trace elements, and especially high content of natural taurine, which can activate the activity of multiple enzymes and promote the metabolism of the Pinctada martensii. The method provided by the present invention can reduce the stress response of the Pinctada martensii to hypoxia, have a protective effect on body tissues, and thus can significantly improve the tolerance of the Pinctada martensii to long-term hypoxia, and appropriate hypoxia training will not cause the death of the Pinctada martensii. DETAILED DESCRIPTION

[0024] The present invention provides a method for improving the hypoxia tolerance of Pinctada martensii, comprising the following steps:

[0025] 1) After 1.5-2 years old Pinctada martensii are subjected to hypoxia training, they are fattened in natural sea areas to obtain Pinctada martensii oysters with mature gonads;

[0026] 2) breeding the Pinctada martensii with mature gonads to obtain Pinctada martensii seedlings with a shell height of 2 to 4 mm; the breeding method comprises: feeding unicellular algae every day from the D-shaped larvae to the larval attachment stage, and feeding a nutrient solution every 3 days; the unicellular algae are cultivated in a culture solution containing the nutrient solution;

[0027] The preparation method of the nutrient solution comprises: opening the shells of some of the Pinctada martensii oysters with mature gonads that have undergone hypoxia training, collecting shellfish meat and mucus that flows out; mixing the shellfish meat with sterilized seawater, blending the mixture, and filtering to obtain a supernatant; and mixing the mucus with the supernatant to obtain the nutrient solution;

[0028] 3) moving the Pinctada martensii seedlings to a sea area for cultivation, and subjecting the Pinctada martensii seedlings to hypoxia training when they grow to a shell height of 2 to 3 cm, thereby obtaining Pinctada martensii with improved hypoxia tolerance;

[0029] The hypoxia training comprises: subjecting the Pinctada martensii or Pinctada martensii seedlings to hypoxia treatment and recovery treatment in aquaculture seawater in sequence, repeating the hypoxia treatment and recovery treatment 6 to 8 times in total; during the hypoxia treatment, the dissolved oxygen of the aquaculture seawater is 1.5 to 2.0 mg / L, and the time of each hypoxia treatment is 20 to 24 hours; during the recovery treatment, the dissolved oxygen of the aquaculture seawater is ≥6.0 mg / L, and the time of each recovery treatment is 45 to 48 hours.

[0030] The present invention subjects 1.5-2 year old Pinctada martensii to hypoxia training and then fattens them in a natural sea area to obtain Pinctada martensii with mature gonads. As an embodiment, during the hypoxia training, the hypoxia treatment and recovery treatment are repeated 7 times in total; during the hypoxia treatment, the dissolved oxygen of the aquaculture seawater is 1.5 mg / L, and the time of each hypoxia treatment is 20 hours; during the recovery treatment, the dissolved oxygen of the aquaculture seawater is 6.0 mg / L, and the time of each recovery treatment is 45 hours.

[0031] As an embodiment, the method for controlling the dissolved oxygen of the aquaculture seawater during the hypoxia treatment includes: introducing nitrogen and air into the aquaculture seawater, and controlling the dissolved oxygen content of the aquaculture seawater by adjusting the intake of nitrogen and air. As an embodiment, the method for fattening includes: hanging the Pinctada martensii oysters after hypoxia training in a natural sea area for fattening.

[0032] After obtaining the Pinctada martensii with mature gonads, the present invention breeds the Pinctada martensii with mature gonads to cultivate Pinctada martensii seedlings with a shell height of 2 to 4 mm; the cultivation method comprises: feeding unicellular algae every day from the D-shaped larvae to the larval attachment stage, and feeding nutrient solution every 3 days; the unicellular algae is cultivated by a culture solution containing the nutrient solution; the preparation method of the nutrient solution comprises: opening the shells of some of the Pinctada martensii with mature gonads, collecting shell meat and mucus flowing out; mixing the shell meat with sterilized seawater, crushing it, filtering it to obtain a supernatant; mixing the mucus with the supernatant to obtain the nutrient solution. The nutrient solution of the present invention is prepared and used immediately to keep it fresh. As an implementation mode, unicellular algae are fed every day from the D-shaped larvae to the larval attachment stage. According to the larvae's feeding, digestion and absorption, vitality, growth and development, the basic situation of the larvae is grasped as a whole, and the feeding amount and type of bait (unicellular algae) are flexibly adjusted; the present invention has no special requirements for the adjustment method, and the method well known to those skilled in the art can be used.

[0033] As an embodiment, based on the volume of the larval culture solution, the feeding amount of the nutrient solution each time is 15 to 20 ml / L of the larval culture solution.

[0034] As an embodiment, the unicellular algae include one or more of Isochrysis Zhanjiangensis, Isochrysis Globosum, Platymonas subcordiformis and Dunaliella. As an embodiment, the culture solution for cultivating the unicellular algae includes a basic culture solution and the nutrient solution; the volume ratio of the basic culture solution to the nutrient solution is 100:0.1-0.3. As an embodiment, the basic culture solution includes Zhanshui No. 107-18 culture solution.

[0035] As an implementation mode, the mass ratio of the shellfish meat to the sterilized seawater is 1:3-4.

[0036] As an embodiment, the method for preparing the disinfected seawater includes: filtering natural seawater through a sand filter and a ceramic filter element, and then disinfecting it to obtain the disinfected seawater; the disinfection method includes one or more of ultraviolet irradiation, ozone treatment and high-temperature boiling.

[0037] As an embodiment, the shellfish meat is shellfish meat with the adductor muscle removed and the soft part left.

[0038] As an embodiment, the shell height of the Pinctada martensii with improved hypoxia tolerance is 5 to 7 cm

[0039] The present invention selects suitable Pinctada martensii for hypoxia training, then selects Pinctada martensii with mature gonads after hypoxia training as broodstock for seedling cultivation; extracts nutrient solution from the Pinctada martensii trained with hypoxia; feeds nutrient solution to the larvae and juveniles of Pinctada martensii for nutritional fortification cultivation in the seedling stage, and adds nutrient solution to the unicellular algae culture to fortify the algae nutrition. The method provided by the present invention can enhance the physique of Pinctada martensii, produce a protective effect on body tissues, reduce the stress response of Pinctada martensii to hypoxia, and can significantly improve the tolerance of Pinctada martensii to long-term hypoxia.

[0040] In order to further illustrate the present invention, a method for improving the hypoxia tolerance of Pinctada martensii provided by the present invention is described in detail below in conjunction with examples, but they should not be construed as limiting the scope of protection of the present invention.

[0041] Example 1

[0042] A method for improving the hypoxia tolerance of Pinctada martensii, as follows:

[0043] (1) In March 2020, 600 1.5-year-old Pinctada martensii oysters were selected and raised in a 2000-liter round plastic barrel. The dissolved oxygen content of seawater was controlled to 1.5 mg / L by adjusting the amount of nitrogen and air introduced, and maintained for 20 hours to treat the Pinctada martensii with hypoxia; after 20 hours, the dissolved oxygen content of seawater was adjusted to 6.0 mg / L, and the treatment time was 45 hours; the hypoxia treatment and recovery treatment were repeated 6 times in total; the Pinctada martensii oysters after hypoxia training were raised in natural sea areas for fattening, and the Pinctada martensii oysters with mature gonads were obtained.

[0044] (2) Selecting the Pinctada martensii oysters with mature gonads in step (1) for artificial breeding to cultivate Pinctada martensii seedlings. During the cultivation of Pinctada martensii seedlings, nutritional fortification cultivation is performed, and from the D-shaped larvae to the attachment stage, the seedlings are fed with Isochrysis zhanjiangensis, Isochrysis globosum, Platymonas subcordiformis and Dunaliella as additives, and the seedlings are fed with nutrient solution once every 3 days, and the feeding amount is 15 ml / L.

[0045] The method for preparing the nutrient solution comprises the following steps: selecting the Pinctada martensii oysters cultivated by hypoxia training in step (1), washing them clean, cutting off the adductor muscle, collecting the mucus flowing out after opening the shell, removing the adductor muscle and leaving the soft body part, adding 3 kg of sterilized seawater to every 1 kg of Pinctada martensii meat without the adductor muscle, stirring and filtering to obtain a supernatant; mixing the mucus and the supernatant to obtain the nutrient solution; and preparing and using the nutrient solution immediately to keep it fresh.

[0046] The sterilized seawater used to prepare the nutrient solution is natural seawater that has been filtered twice through a sand filter and a ceramic filter element, and then treated with ultraviolet light.

[0047] The single-cell algae culture is carried out using a culture solution formula of Zhanshui No. 107-18, with 0.1% (v / v) nutrient solution added, and using a conventional method for microalgae culture.

[0048] (3) After the Pinctada martensii seedlings cultivated in step (2) grow to a shell height of 2 mm, they are transferred to a natural sea area for oyster culture, and cultured and managed according to conventional methods.

[0049] (4) When the juvenile spat cultured in the sea area grows to a shell height of 2.0 cm, it is transferred from the sea area to a cement pool on the shore for hypoxia training; the hypoxia training is:

[0050] a. Pump nitrogen and air into the aquaculture seawater, and adjust the air intake of the two to keep the dissolved oxygen in the aquaculture seawater in the cement pool at 1.5 mg / L for 20 hours;

[0051] b. After 20 hours, the nitrogen and air intake was adjusted to maintain the dissolved oxygen in the aquaculture seawater at 6.0 mg / L for 45 hours;

[0052] c. Repeat steps a and b 6 times.

[0053] (5) The Pinctada martensii oysters that have undergone hypoxia training are moved to the sea area for culture. When the oysters grow to a shell height of 5 to 7 cm, the Pinctada martensii oysters with improved hypoxia tolerance are obtained.

[0054] Example 2

[0055] A method for improving the hypoxia tolerance of Pinctada martensii, as follows:

[0056] (1) In March 2021, 800 1.5-year-old Pinctada martensii oysters were selected and raised in a 2500L round plastic barrel. The dissolved oxygen content of seawater was controlled to 2 mg / L by adjusting the amount of nitrogen and air introduced, and maintained for 24 hours to treat the Pinctada martensii with hypoxia; after 24 hours, the dissolved oxygen content of seawater was adjusted to 6.5 mg / L, and the treatment time was 48 hours; the hypoxia treatment and recovery treatment were repeated 8 times in total; the Pinctada martensii oysters after hypoxia training were raised in natural sea areas for fattening, and the Pinctada martensii oysters with mature gonads were obtained.

[0057] (2) Selecting the Pinctada martensii oysters with mature gonads in step (1) for artificial breeding to cultivate Pinctada martensii seedlings. During the cultivation of Pinctada martensii seedlings, nutritional fortification cultivation is performed, and Isochrysis zhanjiangensis, Isochrysis globosum, Platymonas subcordiformis and Dunaliella are cultivated with nutrient solution as an additive every day, and the nutrient solution is fed once every 3 days, and the feeding amount is 20 ml / L.

[0058] The method for preparing the nutrient solution is as follows: select the Pinctada martensii cultivated by hypoxia training in step 1, wash and clean them, cut off the adductor muscle, collect the mucus flowing out after opening the shell, remove the adductor muscle and leave the soft body part, add 4 kg of sterilized seawater to every 1 kg of Pinctada martensii meat without the adductor muscle, stir and filter to obtain a supernatant; mix the mucus and the supernatant to obtain the nutrient solution; prepare and use it immediately to keep it fresh.

[0059] The sterilized seawater used to prepare the nutrient solution is natural seawater that has been filtered twice through a sand filter and a ceramic filter element, and then sterilized with ozone.

[0060] The single-cell algae culture is carried out using a culture solution formula of Zhanshui No. 107-18, with 0.3% of nutrient solution added, and using a conventional method for microalgae culture.

[0061] (3) After the Pinctada martensii seedlings cultivated in step (2) grow to a shell height of 4 mm, they are transferred to natural sea areas for oyster culture, and cultured and managed according to conventional methods.

[0062] (4) When the juvenile spat cultured in the sea area grows to a shell height of 3.0 cm, it is transferred from the sea area to a cement pool on the shore for hypoxia training; the hypoxia training is:

[0063] a. Pump nitrogen and air into the aquaculture seawater, and adjust the air intake of the two to keep the dissolved oxygen in the aquaculture seawater in the cement pool at 2 mg / L for 24 hours;

[0064] b. After 24 hours, the nitrogen and air intake was adjusted to maintain the dissolved oxygen in the aquaculture seawater at 6.5 mg / L for 48 hours;

[0065] c. Repeat steps a and b 8 times in total.

[0066] (5) The Pinctada martensii oysters that have undergone hypoxia training are moved to the sea area for culture. When the oysters grow to a shell height of 5 to 7 cm, the Pinctada martensii oysters with improved hypoxia tolerance are obtained.

[0067] Example 3

[0068] A method for improving the hypoxia tolerance of Pinctada martensii, as follows:

[0069] (1) In April 2021, 1000 2-year-old Pinctada martensii oysters were selected and raised in a 3000L round plastic barrel. The dissolved oxygen content of seawater was controlled to 1.8 mg / L by adjusting the amount of nitrogen and air introduced, and maintained for 22 hours to treat the Pinctada martensii with hypoxia; after 22 hours, the dissolved oxygen content of seawater was adjusted to 7 mg / L, and the treatment time was 46 hours; the hypoxia treatment and recovery treatment were repeated 7 times in total; the Pinctada martensii oysters after hypoxia training were raised in natural sea areas for fattening, and the Pinctada martensii oysters with mature gonads were obtained.

[0070] (2) Selecting the Pinctada martensii oysters with mature gonads in step (1) for artificial breeding to cultivate Pinctada martensii seedlings. During the cultivation of Pinctada martensii seedlings, nutritional fortification cultivation is performed, and from the D-shaped larvae to the attachment stage, the seedlings are fed with Isochrysis zhanjiangensis, Isochrysis globosum, Platymonas subcordiformis and Dunaliella as additives, and the seedlings are fed with nutrient solution once every 3 days, with a feeding amount of 18 ml / L.

[0071] The method for preparing the nutrient solution is as follows: select the Pinctada martensii cultivated by hypoxia training in step 1, wash and clean them, cut off the adductor muscle, collect the mucus flowing out after opening the shell, remove the adductor muscle and leave the soft body part, add 3.5 kg of sterilized seawater to every 1 kg of Pinctada martensii meat without the adductor muscle, stir and filter to obtain the supernatant; mix the mucus and the supernatant to form the nutrient solution; prepare and use it immediately to keep it fresh.

[0072] The sterilized seawater used to prepare the nutrient solution is natural seawater that has been filtered twice through a sand filter and a ceramic filter element, and then sterilized at high temperature.

[0073] The single-cell algae culture is carried out using the culture solution formula of Zhanshui No. 107-18, with 0.2% of nutrient solution added, and using the conventional method of microalgae culture for culture.

[0074] (3) After the Pinctada martensii seedlings cultivated in step (2) grow to a shell height of 3 mm, they are transferred to natural sea areas for cultivation and are cultivated and managed according to conventional methods.

[0075] (4) When the juvenile spat cultured in the sea area grows to a shell height of 2.5 cm, it is transferred from the sea area to a cement pool on the shore for hypoxia training; the hypoxia training is:

[0076] a. Pump nitrogen and air into the aquaculture seawater, and adjust the air intake of the two to keep the dissolved oxygen in the aquaculture seawater in the cement pool at 1.8 mg / L for 22 hours;

[0077] b. After 22 hours, the nitrogen and air intake was adjusted to maintain the dissolved oxygen in the aquaculture seawater at 7 mg / L for 46 hours;

[0078] c. Repeat steps a and b 7 times in total.

[0079] (5) The Pinctada martensii oysters that have undergone hypoxia training are moved to the sea area for culture. When the oysters grow to a shell height of 5 to 7 cm, the Pinctada martensii oysters with improved hypoxia tolerance are obtained.

[0080] Comparative Example 1

[0081] In March 2020, 1.5-year-old Pinctada martensii oysters with mature gonads cultured in natural sea areas were selected as broodstock, and artificial seedlings were raised according to conventional methods (refer to [Chen Weiyao, Liao Yongshan. High-yield seedling raising technology of Pinctada martensii [J]. Scientific Fish Farming, 2021. DOI: 10.3969 / j.issn.1004-843X.2021.03.035.]). After the Pinctada martensii seedlings grew to an average shell height of 2 mm, they were transferred to natural sea areas for culture according to conventional methods, and the mother oysters were harvested when they grew to a shell height of 5-7 cm.

[0082] Comparative Example 2

[0083] In March 2021, 1.5-year-old Pinctada martensii oysters with mature gonads cultured in natural sea areas were selected as broodstock, and artificial seedlings were raised according to conventional methods (refer to [Chen Weiyao, Liao Yongshan. High-yield seedling raising technology of Pinctada martensii [J]. Scientific Fish Farming, 2021. DOI: 10.3969 / j.issn.1004-843X.2021.03.035.]). After the Pinctada martensii seedlings grew to an average shell height of 3mm, they were transferred to natural sea areas for culture according to conventional methods, and the mother oysters were harvested when they grew to a shell height of 5-7cm.

[0084] Comparative Example 3

[0085] In April 2021, 2-year-old Pinctada martensii oysters with mature gonads cultured in natural sea areas were selected as broodstock, and artificial seedlings were raised according to conventional methods (refer to [Chen Weiyao, Liao Yongshan. High-yield seedling raising technology of Pinctada martensii [J]. Scientific Fish Farming, 2021. DOI: 10.3969 / j.issn.1004-843X.2021.03.035.]). After the Pinctada martensii seedlings grew to an average shell height of 3mm, they were transferred to natural sea areas for culture according to conventional methods, and the mother oysters were harvested when they grew to a shell height of 5-7cm.

[0086] Test Example 1

[0087] In 2023, the Pinctada martensii of Examples 1 to 3 and Comparative Examples 1 to 3 were subjected to hypoxia stress experiments, with 100 in each group, and three parallel repeated experiments were performed, as follows:

[0088] Nitrogen and air were pumped into the culture seawater, and the dissolved oxygen in the seawater was maintained at 2.0 mg / L by adjusting. After 6 cm Pinctada martensii was placed in this environment, the mortality of Pinctada martensii was counted on the 13th, 14th and 15th days. The results are shown in Table 1.

[0089] Table 1 Mortality of Pinctada martensii in different culture methods (%)

[0090] Group 13-day mortality rate 14-day mortality 15-day mortality Example 1 26 30 37 Example 2 28 29 35 Example 3 25 28 34 Comparative Example 1 34 43 54 Comparative Example 2 32 36 48 Comparative Example 3 31 34 49

[0091] As can be seen from Table 1, the method provided by the present invention can improve the hypoxia tolerance of Pinctada martensii, and can significantly improve the survival rate of Pinctada martensii cultured in sea areas by carrying out sea area culture of Pinctada martensii.

[0092] Although the above embodiment describes the present invention in detail, it is only a part of the embodiments of the present invention, not all of the embodiments. People can also obtain other embodiments based on this embodiment without creativity, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A method for improving the hypoxia tolerance of Pinctada martensii, characterized in that: The following steps are involved: 1) After 1.5-2 years old Pinctada martensii are subjected to hypoxia training, they are fattened in natural sea areas to obtain Pinctada martensii oysters with mature gonads; 2) breeding the Pinctada martensii with mature gonads to obtain Pinctada martensii seedlings with a shell height of 2 to 4 mm; the breeding method comprises: feeding unicellular algae every day from the D-shaped larvae to the larval attachment stage, and feeding a nutrient solution every 3 days; the unicellular algae are cultivated in a culture solution containing the nutrient solution; The preparation method of the nutrient solution comprises: opening the shells of some of the Pinctada martensii oysters with mature gonads that have undergone hypoxia training, collecting shellfish meat and mucus that flows out; mixing the shellfish meat with sterilized seawater, blending the mixture, and filtering to obtain a supernatant; and mixing the mucus with the supernatant to obtain the nutrient solution; 3) moving the Pinctada martensii seedlings to a sea area for cultivation, and subjecting the Pinctada martensii seedlings to hypoxia training when they grow to a shell height of 2 to 3 cm, thereby obtaining Pinctada martensii with improved hypoxia tolerance; The hypoxia training comprises: subjecting the Pinctada martensii or Pinctada martensii seedlings to hypoxia treatment and recovery treatment in aquaculture seawater in sequence, repeating the hypoxia treatment and recovery treatment 6 to 8 times in total; during the hypoxia treatment, the dissolved oxygen of the aquaculture seawater is 1.5 to 2.0 mg / L, and the time of each hypoxia treatment is 20 to 24 hours; during the recovery treatment, the dissolved oxygen of the aquaculture seawater is ≥6.0 mg / L, and the time of each recovery treatment is 45 to 48 hours.

2. The method according to claim 1, characterized in that: Calculated by the volume of the larval culture solution, the feeding amount of the nutrient solution each time is 15-20 ml / L larval culture solution.

3. The method according to claim 1, characterized in that The method for controlling dissolved oxygen in aquaculture seawater during hypoxia treatment comprises: introducing nitrogen and air into the aquaculture seawater, and controlling the dissolved oxygen content of the aquaculture seawater by adjusting the intake of nitrogen and air.

4. The method according to claim 1, characterized in that: The unicellular algae include one or more of Isochrysis zhanjiangensis, Isochrysis galbana, Platymonas subcordiformis and Dunaliella.

5. The method according to claim 1 or 4, characterized in that: The culture solution for cultivating the unicellular algae includes a basic culture solution and the nutrient solution; the volume ratio of the basic culture solution to the nutrient solution is 100:0.1-0.

3.

6. The method according to claim 5, characterized in that The basic culture medium includes Zhanshui No. 107-18 culture medium.

7. The method according to claim 1, characterized in that The mass ratio of the shellfish meat to the sterilized seawater is 1:3-4.

8. The method according to claim 1 or 7, characterized in that: The preparation method of the sterilized seawater comprises: filtering natural seawater through a sand filter and a ceramic filter element, and then sterilizing the natural seawater to obtain the sterilized seawater; the sterilization method comprises one or more of ultraviolet irradiation, ozone treatment and high-temperature boiling.

9. The method according to claim 1 or 7, characterized in that: The shellfish meat is shellfish meat with the adductor muscle removed and the soft part left.

10. The method according to claim 1, characterized in that The shell height of the Pinctada martensii with improved hypoxia tolerance is 5 to 7 cm.