Method for crossbreeding babylonia lutosa and babylonia formosana

Abstract

The invention relates to a crossbreeding method for babylonia lutosa and babylonia taiwan. The cross breeding method comprises the following steps: putting Babylonia taiwanensis and Babylonia lutosa into independent units in a dark environment for breeding, hybridizing, collecting oocysts, disinfecting the oocysts, and hatching to obtain Babylonia lutosa planktonic larvae; a fertilizer water agent and a nutritional agent are applied to culture water of babylonia planktonic larvae, unicellular algae are mixed for culture, and the babylonia planktonic larvae are metamorphosed and attached to form juvenile snails. Compared with the existing Babylonia taiwanensis and Babylonia lutosa, the Babylonia lutosa hybrid fry bred by the crossbreeding method not only has more excellent metamorphosis rate, but also has significantly improved fertilization rate, egg laying amount, hatching rate and larva survival rate.

Description

Technical Field

[0001] The invention belongs to the technical field of shellfish breeding, and more specifically, relates to a hybrid breeding method of Babylonia truncatula and Babylonia formosanus. Background Art

[0002] Babyonia lutosa belongs to the class Gastroroda, order Neogastropoda, family Bucinidae, genus Babylonia of the mollusk. It is commonly known as "yellow snail" or "mud snail". Its shell is long and oval, 30 to 80 mm high, with a smooth shell surface, a small spiral part, an enlarged body whorl, about 8 layers, each of which is relatively swollen and has an operculum. It is distributed in the coastal areas from Fujian to Guangxi in my country and is an important marine economic edible shellfish in my country.

[0003] The main types of baby conchs farmed in my country include the square-spotted baby conch, mud baby conch and Taiwan baby conch. Mud baby conch is also called mist flower conch and is mainly distributed along the coasts of Zhejiang, Fujian and Guangdong. The baby conch farmed in Fujian is also called Fujian mud baby conch. Taiwan baby conch is also called Taiwan conch and is mainly distributed in the waters of Taiwan, my country.

[0004] Hybrid breeding is essentially the re-aggregation of genetic resources between different parents. It can quickly break the original genetic conservatism and make the hybrids have greater genetic mobility. It is an important way to increase variation and can quickly and significantly improve the vitality, growth and other excellent traits of hybrid offspring. It is of great significance in the genetic improvement of shellfish. Therefore, hybrid breeding has also become an important direction for genetic improvement research of Babylonia conch.

[0005] "Progress in Research on Biology and Genetic Breeding of Babylonia, Fu Jingqiang" disclosed that the genetic distance between Babylonia square-spotted, Babylonia mud and Babylonia Taiwan has reached the level of inter-species. In addition, it also mentioned the use of complete double-row hybridization, using the Wengtian population of Babylonia square-spotted in Hainan and the Rayong population of Thailand as materials for long-distance hybridization between populations. The experimental results showed that: in the larval development stage, the hybrid Babylonia snails showed super-parental advantage in both metamorphosis rate and metamorphosis time, with super-parental advantage rates of 8.7% and 20.53%, respectively. However, the above-mentioned increase in the metamorphosis rate of the hybrid Babylonia snails is still difficult to meet the actual needs during seedling and breeding. Summary of the invention

[0006] In response to the above-mentioned existing technical problems, the primary purpose of the present invention is to provide a hybrid breeding method for mud snails and Taiwan snails. Compared with the existing Taiwan snails and mud snails, the hybrid snail seedlings bred by the hybrid breeding method not only have a better metamorphosis rate, but also have significantly improved fertilization rate, egg laying rate, hatching rate and larval survival rate.

[0007] In order to achieve the above object, the present invention is implemented by the following technical solutions:

[0008] The present invention claims protection for a hybrid breeding method of Babylonia fuscata and Babylonia formosanus, comprising the following steps:

[0009] S1. Place the Taiwan Babylonia and the mud Babylonia in a separate unit in a dark environment for breeding, hybridize and collect the egg cysts, disinfect the egg cysts and hatch them to obtain the planktonic larvae of the Babylonia;

[0010] S2. Fertilizers and nutrients are applied to the water bodies where the planktonic larvae of the Babylonia snails are cultured, and unicellular algae are mixed in for cultivation. The planktonic larvae of the Babylonia snails undergo metamorphosis and attach to form juvenile snails.

[0011] Preferably, in step S1, the ratio of female Babylonia snails to male Babylonia snails is 1:1-2. Specifically, in the present invention, male Taiwan Babylonia snails and female mud Babylonia snails can be selected for pairing, or male mud Babylonia snails and female Taiwan Babylonia snails can be selected for pairing. In the present invention, the same sex of Babylonia snails are always the same species.

[0012] Specifically, in the present invention, the shell surface color of the Taiwan baby conch is light brown, and the pattern is light brown and relatively continuous and irregular. The mud baby conch is the Fujian mud baby conch, and the shell surface color is mud yellow, the shell mouth is purple-red, and the pattern is unclear.

[0013] The inventors found through research that the Taiwan Babylonia snails and Fujian Babylonia snails were first cultured in separate units in a dark environment, and Babylonia snails were more likely to mate in dark conditions. Furthermore, the inventors were surprised to find that compared with the existing Taiwan Babylonia snails and Fujian Babylonia snails, hybrid breeding using the above two Babylonia snails can break the original genetic conservatism, and the hybrid Babylonia snail seedlings have better egg production, fertilization rate and hatching rate.

[0014] Furthermore, the inventors found through research that during the period when the hybrid baby snail develops from larvae to young snails, the use of fertilizer and water agent in combination with nutrient agent can improve the efficiency of seedling cultivation. The rich nutritional value of fertilizer and water agent can promote the rapid reproduction of unicellular algae in the water body, maintain the balance of algae and fungi in the water body, is not easily affected by weather changes (high temperature, low temperature, rainy), quickly replenishes water nutrients, and reduces the stress response of larvae to environmental changes. Nutrients include soybean phosphatidylcholine and cecropin. Soybean phosphatidylcholine is a kind of phospholipid with a choline group. It is an important component of biofilm and can be used as a growth promoter, feed enhancer, immunomodulator and antioxidant activity stimulator for larvae. In addition, soybean phosphatidylcholine can also help larvae resist physical and chemical stress, which is crucial for the rapid growth of baby snails in the early development stage. In addition to having a broad spectrum of inhibitory or killing bacterial activity, cecropin also has an immunomodulatory effect, enhances the nonspecific immune function of the body, and exerts an antibacterial function. By combining fertilizers and water agents with nutrients, the metamorphosis rate of hybrid snail seedlings, the survival rate of planktonic larvae of snails and the yield of juvenile snails were significantly improved.

[0015] Specifically, Taiwan Babylonia and Mud Babylonia can be selected from species with healthy snail bodies, good vitality, quick reactions, good shell color, soft and plump abdominal feet, tightly closed operculum, no external injuries, full gonads, shell height of 4 to 7 cm, and weight of 15 to 50 grams. More specifically, Taiwan Babylonia and Mud Babylonia can be selected from farmed Babylonia or wild Babylonia. When wild Babylonia can be selected, Babylonia captured by cages and ambush can be selected. Babylonia captured by cages and ambush are not easily mechanically damaged and thus infected with bacteria.

[0016] Specifically, the independent unit may be a breeding barrel, a breeding box, etc. The baby snails may be released by setting a feeding port on the top of the independent unit, or a highly transparent observation window may be set on the front of the independent unit to observe biological behaviors such as mating and spawning of baby snails.

[0017] Preferably, in step S1, bait is fed during the breeding process.

[0018] Preferably, the bait comprises one or more of prawns, scallop meat, Manila clam meat or oyster meat.

[0019] Preferably, in step S2, the water fertilizer comprises 5-10 g urea, 1-3 g dipotassium hydrogen phosphate, 3-5 g sodium nitrate, 1-2 g sodium silicate, 0.001-0.1 g ferric citrate, 0.05-0.5 g vitamin B1, 0.001-0.05 g vitamin B 12 .

[0020] Further preferably, the water fertilizer comprises 8-10 g urea, 2-3 g dipotassium hydrogen phosphate, 4-5 g sodium nitrate, 1-1.5 g sodium silicate, 0.01-0.08 g ferric citrate, 0.1-0.3 g vitamin B1, 0.002-0.008 g vitamin B 12 .

[0021] Preferably, in step S2, the nutrient comprises soybean phosphatidylcholine and cecropin in a mass ratio of 0.1-0.3:3-6.

[0022] Preferably, in step S2, the dosage of the nutrient in the aquaculture water is 3.0-3.5 ppm.

[0023] Preferably, in step S2, the unicellular algae include one or more of Chlorella, Pseudochloropsis, Chaetoceros muelleri, Thalassiosira schrenkiana, Nitzschia closterium, and Phaeochromis tricornutum.

[0024] Preferably, in step S2, the cultivation conditions are: water temperature 20-30°C, seawater specific gravity 1.018-1.024 g / mL, pH 8.4-8.7.

[0025] Preferably, in step S1, the disinfection treatment is: first soaking in a disinfectant for 10 to 20 seconds, then washing off the residual povidone-iodine with fresh water, and finally rinsing with sea water. More specifically, the disinfectant can be a disinfectant conventionally used for disinfection of Dongfeng snail egg cysts in the art, such as povidone-iodine.

[0026] Preferably, in step S1, during the hybridization process, water flows continuously for 24 hours to ensure the stability of the breeding sand and water quality.

[0027] Preferably, in step S2, the density of cultivating the planktonic larvae of Babylonia sinensis is 0.1 to 0.2 larvae / mL.

[0028] Preferably, in step S2, the young snails are cultured into adult snails and then mixed, and then cultured using the methods of step S1 and step S2.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] The present invention provides a hybrid breeding method of Babylonia sphaeroides and Babylonia formosanus. The Babylonia hybrid seedlings obtained by the above method not only have a more excellent metamorphosis rate, but also have significantly improved fertilization rate, egg laying amount, hatching rate, and larval survival rate, which are significantly higher than those of common Babylonia formosanus and Babylonia sphaeroides. The present invention uses hybrid breeding to form a new variety of Babylonia sphaeroides, enriches the germplasm types of Babylonia sphaeroides, and ensures the healthy, green and sustainable development of the Babylonia sphaeroides industry. DETAILED DESCRIPTION

[0031] The present invention is further described below with reference to specific examples, but the examples do not limit the present invention in any form. Unless otherwise specified, the reagents, methods and equipment used in the present invention are conventional reagents, methods and equipment in the art.

[0032] Example 1: Hybrid breeding method of Taiwan babylonia and Fujian babylonia

[0033] (1) Collect healthy, energetic, quick-reacting, good-colored shells, soft and plump abdominal feet, tightly closed opercula, no external injuries, and full gonads of Fujian mud snails and Taiwan snails. The male and female can be distinguished by the presence or absence of genital pores. Female Taiwan snails and male Fujian mud snails are paired in independent cells (cultivation boxes) in a ratio of 1:2. 200 independent cells are paired and placed in a dark environment for cultivation (scallop meat accounting for 12% of the snail's body weight is fed during the cultivation process) and hybridization. During the hybridization process, water is continuously flowing for 24 hours to ensure the stability of sand and water quality.

[0034] (2) Hybridization to collect egg sacs. Egg sacs are light yellow when they are first produced. They are composed of multiple egg sacs, which contain hundreds or thousands of fertilized eggs suspended in the viscous endosperm. They are spherical or elliptical in shape. The egg sacs are taken out with a scoop net and first subjected to a concentration of 80×10 -6 Soak the fish in povidone-iodine for 10 seconds, then wash off the residual povidone-iodine with fresh water, and finally rinse with sea water and move them into the nursery pond. During the incubation period, change the water twice a day, each time changing 100%.

[0035] (3) Inject seawater filtered by a 200-mesh mesh bag as the aquaculture water for hatching the planktonic larvae of the baby snails, and apply fertilizer to the aquaculture water (per ton of aquaculture water, the fertilizer includes 8 grams of urea, 2 grams of dipotassium hydrogen phosphate, 4 grams of sodium nitrate, 1 gram of sodium silicate, 0.05 grams of ferric citrate, 0.1 grams of vitamin B1, 0.005 grams of vitamin B 12 After 7 days of cultivation, a variety of unicellular algae (including Chlorella, Pseudo-Nannochloropsis, Chaetoceros muelleri, Thalassiosira, Nitzschia closterium and Phaeochromis triangularis) were grown in the water, and the algae cell concentration in the algae culture pool reached 1.0×10 5 ~2.0×10 5 / ml, and start pumping it into the nursery pond for feeding.

[0036] (4) The aquaculture water is disinfected with ultraviolet light, filtered with 1 micron precision filter cotton to remove impurities, and ethylenediaminetetraacetic acid (EDTA) is added to maintain 3 mg / L to complex heavy metals. The culture density of the planktonic larvae of the baby snail is 0.1 / mL, and the water is changed twice a day, with 50% of the water changed each time (80 mesh is used for the early water change, and 60 mesh is used in the middle and late stages). The unicellular algae of step (3) are fed, and nutrients are used during the period (the nutrients include soybean phosphatidylcholine and cecropin. Based on the aquaculture water, the amount of soybean phosphatidylcholine is 0.1ppm, and the amount of cecropin is 3ppm). The nutrients are used once a day. When cultivated under the conditions of water temperature of 27-28℃, seawater specific gravity of 1.021 and pH (aquaculture water pH) of 8.4-8.7, the planktonic larvae of Dongfeng snail will float for 13 days and when the shell height reaches about 1100 microns, the larvae will develop close to the creeping larvae stage and begin to show signs of attachment, completing the attachment and becoming juvenile snails.

[0037] Example 2: Hybrid breeding method of Taiwan Babylonia taiwanensis and Fujian Babylonia fujianensis

[0038] The difference between this embodiment and embodiment 1 is that the female Fujian Babylonia fujianensis and the male Taiwan Babylonia taiwanensis are paired in independent cells in a ratio of 1:2.

[0039] Example 3: Cultivation of hybrid snail seedlings of Babylonia Taiwana and Babylonia Fujiana

[0040] The juvenile snails obtained by hybridizing the Taiwan Babylonia snails bred in Example 1 with the Fujian Babylonia snails were selected for breeding.

[0041] The specification of young snails is 4180 grains / kg, and 1500 grains / m 2 The density of the stocking is in a breeding pond with a length, width and height of 2.0m×5.0m×0.8m respectively. The bottom of the breeding pond is laid with a black checkered plastic board with a height of 10cm, and a 60-mesh silk screen is laid on the plastic board, and then the sand layer is laid with a thickness of 6cm. The flow-through breeding method is adopted. Natural seawater is extracted from the seaside sand filter and filtered through the sand filter tank for breeding experiments. The salinity and temperature are not adjusted. During the breeding period, the specific gravity of seawater is 1.018-1.024g / mL, the water temperature ranges from 28 to 30℃, and the pH is 8.4 to 8.6. Feed is thrown at 17:00 every day, and the residual bait is collected after 1 hour. The water temperature and salinity are measured at 10:00 am every day. Under normal circumstances, the time for sand washing is determined according to the degree of bottom sand pollution. Disinfect with bleach once a week. Pay attention to the feeding and activity of the mixed wind snails every day, treat the diseases in time, and clean up and record the dead snails in time. The breeding cycle is 12 months.

[0042] Example 4: Cultivation of hybrid snail seedlings of Babylonia Taiwana and Babylonia Fujiana

[0043] The difference between this embodiment and embodiment 3 is that the young snails obtained by hybridizing the Taiwan Babylonia snails bred in embodiment 2 and the Fujian Babylonia snails are selected for breeding.

[0044] Comparative Example 1

[0045] The difference between this comparative example and Example 1 is that a female Babylonia fujianensis and a male Babylonia fujianensis were used for mating.

[0046] Comparative Example 2

[0047] The difference between this comparative example and Example 1 is that a female Taiwan Babylonia Taiwania and a male Taiwan Babylonia Taiwania were used for mating.

[0048] Comparative Example 3

[0049] The difference between this comparative example and Example 3 is that the baby snails of the Babylonia sinensis of Comparative Example 1 after mating are used for breeding.

[0050] Comparative Example 4

[0051] The difference between this comparative example and Example 3 is that the baby snails of the Babylonia Taiwanii of Comparative Example 2 are used for breeding.

[0052] Comparative Example 5

[0053] The difference between this comparative example and Example 1 is that in step (3), no fertilizer agent is used.

[0054] Comparative Example 6

[0055] The difference between this comparative example and Example 1 is that in step (4), no nutrient agent is used.

[0056] Comparative Example 7

[0057] The difference between this comparative example and Example 3 is that the young snails obtained by cross breeding in Comparative Example 5 are used for breeding.

[0058] Comparative Example 8

[0059] The difference between this comparative example and Example 3 is that the young snails obtained by cross breeding in Comparative Example 6 are used for breeding.

[0060] Test Example 1

[0061] The breeding effects of the above-mentioned Examples 3-4, Comparative Examples 3-4 and Comparative Examples 7-8 were tested, counted and compared, as shown in Table 1.

[0062] Weight at the end of the test: Perform three random operations, select 1000 grams of snails each time, and count the number of snails. Then divide 3000 by the total number of snails, and the calculated value is the average weight of each snail at the end of the test, that is, the weight at the end of the test.

[0063] Weight at the beginning of the test: Randomly perform the operation three times, select 50 grams of snails each time, and count the number of snails. Then divide 150 by the total number of snails, and the calculated value is the average weight of each snail at the beginning of the test, that is, the weight at the beginning of the test.

[0064] The number of Babylonia snails at the end of the experiment: weigh the total weight of all snails in the breeding pond and divide it by the body weight at the end of the experiment to get the number of Babylonia snails at the end of the experiment.

[0065] The number of Babylonia snails at the beginning of the experiment: Weigh the total weight of snail seedlings put into the pond, and divide it by the body weight at the beginning of the experiment to get the number of Babylonia snails at the beginning of the experiment.

[0066] The specification is the range of the number of snails per kilogram at the end of the test.

[0067] Weight gain rate (%) = (body weight at the end of the test - body weight at the start of the test) / body weight at the start of the test × 100%.

[0068] Feed coefficient = total weight of bait consumed / weight of the snails when harvested.

[0069] Survival rate (%) = number of Babylonia snails at the end of the experiment / number of Babylonia snails at the beginning of the experiment.

[0070] Table 1

[0071] Weight gain% Feed coefficient Survival rate% Specifications (head / catties) Example 3 46.08 5.1 91.4 45-50 Example 4 46.67 5.0 90.7 45-50 Comparative Example 3 36.42 5.8 72.2 55-60 Comparative Example 4 36.64 6.0 73.6 55-60 Comparative Example 7 41.37 5.4 84.34 50-55 Comparative Example 8 40.54 5.5 83.29 50-55

[0072] As shown in Table 1, the weight gain rate, feed coefficient and survival rate of the hybrid baby Babylonia snails of the embodiment are significantly higher than those of the common Taiwan baby Babylonia snails and Fujian mud babylonia snails. In addition, the weight gain rate, feed coefficient and survival rate of the hybrid baby Babylonia snails of the embodiment are also significantly higher than those of the hybrid baby Babylonia snails using only fertilizers or nutrients.

[0073] Test Example 2

[0074] The breeding effects of the above-mentioned embodiments 1-2, comparative examples 1-2 and comparative examples 5-6 were tested. The egg laying amount, fertilization rate, fertilized egg amount, hatching rate, metamorphosis rate, survival rate and young snail yield of the planktonic larvae after breeding were counted. The calculation method is as follows. The specific test results are shown in Table 2.

[0075] Egg laying amount: The egg sacs produced after mating of each embodiment or comparative example were collected, drained and weighed with a balance.

[0076] Fertilization rate: Randomly take 10 oocysts and calculate the number of fertilized eggs and unfertilized eggs in each oocyst. Fertilization rate = number of fertilized eggs in 10 oocysts / (number of fertilized eggs in 10 oocysts + number of unfertilized eggs in 10 oocysts) × 100%.

[0077] Amount of fertilized eggs: Randomly take 50 grams of oocysts, count the number of oocysts, get the number of oocysts per gram, weigh the total weight of oocysts, amount of fertilized eggs = total weight of oocysts × number of oocysts per gram × fertilization rate.

[0078] Hatching rate: the initial number of Babylonia larvae: the three-point sampling method is adopted for sampling, and a 250mL beaker is used to take a cup each at the front, middle and back of the nursery pond. The average number of initial Babylonia larvae per milliliter of water is calculated, and multiplied by the volume of water to obtain the initial number of Babylonia larvae; hatching rate = initial number of Babylonia larvae / number of fertilized eggs × 100%.

[0079] Metamorphosis rate: weigh the total weight of the juvenile snails collected after draining, randomly pick out juvenile snails, weigh 1 gram with an electronic balance (accurate to 0.01), calculate the number of juvenile snails per gram, count 3 times, and multiply the number of juvenile snails per gram by the total weight of juvenile snails (grams) to get the number of attached juvenile snails; Metamorphosis rate = (number of metamorphosed juvenile snails / number of initial Dongfeng snail surface disc larvae) × 100%.

[0080] Survival rate of planktonic larvae of Babylonia: Number of late-stage vesicular larvae of Babylonia: Three-point sampling method was adopted for sampling. A 250mL beaker was used to take a cup each at the front, middle and back of the nursery pond. The average number of late-stage vesicular larvae of Babylonia per milliliter of water was calculated and multiplied by the volume of water to obtain the number of late-stage vesicular larvae of Babylonia; Survival rate of planktonic larvae of Babylonia = number of late-stage vesicular larvae of Babylonia / number of early-stage vesicular larvae of Babylonia × 100%.

[0081] Juvenile snail harvest: weight of juvenile snails collected after cultivation and drained.

[0082] Table 2

[0083] index Example 1 Example 2 Comparative Example 1 Comparative Example 2 Comparative Example 5 Comparative Example 6 Independent cell 200 200 200 200 200 200 Egg laying amount (kg) 2.6 2.5 2.0 1.8 2.2 2.2 Fertilization rate (%) 96.6 97.5 83.4 80.1 90.2 89.9 Hatching rate (%) 95.8 94.0 83.3 81.8 89.4 87.5 Abnormality rate (%) 83.9 80.6 71.0 69.2 76.4 75.1 Survival rate of planktonic larvae of Babylonia fasciatus (%) 88.2 85.5 78.4 73.4 81.3 80.0 Juvenile snail harvest (g) 1266 1247 879 853 1035 1014

[0084] As shown in Table 2 above, the present invention provides a hybrid breeding method of Babylonia sphaeroides and Babylonia taiwanensis, and the obtained Babylonia taiwanensis hybrid seedlings have excellent egg laying amount, fertilization rate, hatching rate, metamorphosis rate, survival rate and yield. Among them, the egg laying amount is ≥2.5kg, the fertilization rate is ≥96.6%, the hatching rate is ≥94.0%, the metamorphosis rate is ≥80.6%, the survival rate of Babylonia taiwanensis planktonic larvae is ≥85.5%, and the harvest of juvenile snails is ≥1247g.

[0085] The egg-laying capacity of the hybrid baby wind snails cultivated by the present invention is increased by 30% and 44.4% respectively compared with that of Fujian mud baby wind snails and Taiwan baby wind snails; the fertilization rate is increased by 15.8% and 20.6% respectively; the hatching rate is increased by 15% and 17.1% respectively; the metamorphosis rate is increased by 18.2% and 21.2% respectively; the survival rate of the planktonic larvae of baby wind snails is increased by 12.5% ​​and 20.2% respectively; and the harvest of juvenile snails is increased by 32.8% and 48.4% respectively.

[0086] The egg-laying capacity of the hybrid seedlings of the baby snails cultivated by the present invention is increased by 13.6% compared with comparative examples 5 and 6; the fertilization rates are respectively increased by 7.1% and 7.5%; the hatching rates are respectively increased by 5.1% and 7.4%; the metamorphosis rates are respectively increased by 5.5% and 7.3%; the survival rates of the planktonic larvae of the baby snails are respectively increased by 5.2% and 6.9%; and the harvest of juvenile snails is respectively increased by 20.5% and 23.0%.

[0087] The foregoing examples are merely illustrative and are used to explain some features of the method of the present invention. The appended claims are intended to require the widest possible range that can be imagined, and the embodiments presented herein are demonstrated by the applicant's actual test results. Therefore, the applicant's intention is that the appended claims are not limited by the selection of examples that illustrate the features of the present invention. Some numerical ranges used in the claims also include sub-ranges therein, and changes in these ranges should also be interpreted as being covered by the appended claims where possible.

Claims

1. A hybrid breeding method of Babylonia fusca and Babylonia formosanus, characterized in that: The following steps are involved: S1. Place the Taiwan Babylonia and the mud Babylonia in a separate unit in a dark environment for breeding, hybridize and collect the egg cysts, disinfect the egg cysts and hatch them to obtain the planktonic larvae of Babylonia; S2. Fertilizers and nutrients are applied to the water bodies where the planktonic larvae of the Babylonia snails are cultured, and unicellular algae are mixed in for cultivation. The planktonic larvae of the Babylonia snails undergo metamorphosis and attach to form juvenile snails.

2. The hybrid breeding method according to claim 1, characterized in that: In the step S1, the ratio of female Babylonia snails to male Babylonia snails is 1:1-2.

3. The hybrid breeding method according to claim 1, characterized in that: In the step S1, feed is fed during the breeding process.

4. The hybrid breeding method according to claim 3, characterized in that: The bait includes one or more of prawns, scallop meat, Manila clam meat or oyster meat.

5. The hybrid breeding method according to claim 1, characterized in that: In step S2, the water fertilizer includes 5-10 grams of urea, 1-3 grams of dipotassium hydrogen phosphate, 3-5 grams of sodium nitrate, 1-2 grams of sodium silicate, 0.001-0.1 grams of ferric citrate, 0.05-0.5 grams of vitamin B1, 0.001-0.05 grams of vitamin B 12 .

6. The hybrid breeding method according to claim 1, characterized in that: In the step S2, the nutrient comprises soybean phosphatidylcholine and cecropin in a mass ratio of 0.1-0.3:3-6.

7. The hybrid breeding method according to claim 1, characterized in that: In the step S2, the dosage of the nutrient in the aquaculture water is 3.0-3.5 ppm.

8. The hybrid breeding method according to claim 1, characterized in that: In step S2, the unicellular algae include one or more of Chlorella vulgaris, Nannochloropsis pseudochlorella, Chaetoceros muelleri, Thalassiosira salina, Nitzschia closterium, and Phaeochromis tricornutum.

9. The hybrid breeding method according to claim 1, characterized in that: In step S2, the cultivation conditions are: water temperature 20-30°C, seawater specific gravity 1.018-1.024 g / mL, pH 8.4-8.

7.

10. The hybrid breeding method according to any one of claims 1 to 9, characterized in that: The mud snail is the Fujian mud snail.