Industrialized breeding and facility breeding method for largemouth bass

Abstract

The invention discloses a factory breeding and facility cultivation method for largemouth bass, and relates to the technical field of largemouth bass cultivation. The specific breeding method comprises the steps of parent fish breeding, fry hatching, fry breeding and adult fish breeding, in the fry breeding step, newly hatched larval bass water spots are bred under the dark condition, pretreated fairy shrimps are adopted as initial feed during breeding, then pretreated fairy shrimp larvae and rotifers are fed, and the young larval bass are bred. The ratio of the rotifers is gradually increased every day until all the rotifers are fed, food conversion domestication is started, 90% of the rotifers and 10% of the fermented artificial compound feed are mixed and fed on the first day after domestication, the proportion of the rotifers is gradually reduced every day, and the proportion of the feed is gradually increased every day until the fries completely adapt to the feed. By means of the fry breeding method, healthy fry which grow neatly and are uniform in size and high in stress resistance can be obtained, and the survival rate and the growth speed of adult fish breeding are increased.

Description

Technical Field

[0001] The invention relates to the technical field of largemouth bass breeding, and in particular to a largemouth bass factory breeding and facility breeding method. Background Art

[0002] Largemouth bass (Micropterus salmoides), commonly known as California bass, has many excellent characteristics such as rapid growth, strong adaptability, delicious meat, and few intramuscular spines. It has been rapidly promoted in many parts of the country, and the scale and output of breeding are showing a steady upward trend. According to the 2024 Fisheries Statistical Yearbook, the national largemouth bass production reached 888,000 tons, making it one of the most important freshwater economic fish in my country, and has effectively promoted the development of local fishery economy. In recent years, with the rapid development of the largemouth bass breeding industry, its seedling breeding and breeding have gradually shifted from pond breeding to factory and facility breeding, which has effectively promoted the adjustment of my country's fishery industry structure and promoted the transformation and upgrading of the largemouth bass breeding industry.

[0003] Largemouth black bass are ferocious carnivorous fish. To achieve artificial breeding, seedling cultivation must be carried out to make them switch from feeding on biological bait to feeding on artificial feed. In the existing factory-based and intensive seedling cultivation, the following problems often occur: (1) Because the digestive system of fry is not fully developed, early feeding of artificial feed will cause indigestion, high deformity rate, slow growth, large differences in fry size, and serious cannibalism of fry; (2) Artemia, the initial bait of largemouth black bass, mainly lives in a high-salt environment. After half an hour in fresh water, its activity ability decreases, which is not conducive to the feeding of fry, resulting in a decrease in the survival rate and vitality of fry; (3) The newly hatched fry have poor stress resistance, and the external environmental conditions easily cause stress response in the fry, resulting in a low survival rate. The above problems lead to high mortality and deformity rates of seedlings, which greatly hinder the large-scale development of aquaculture.

[0004] To address the problem of fry not adapting to feed, the current methods mainly include adjusting feed formula (patent CN 114271406B) or delaying feeding training; to address the problem of Artemia decreasing vitality in fresh water, the main methods include increasing the salinity of the nursery water to extend the survival time of Artemia in the water (patent CN 113796340 B), or spraying soybean milk all over the pond to maintain the survival time (patent CN 114946715 B); to address the problem of stress response, the main method is spraying anti-stress drugs (CN 114946715 B). All of these methods have certain effects, but some methods will also have some new problems, such as increased costs, environmental changes affecting the growth of fry, etc., and further improvements are needed. Summary of the invention

[0005] In view of the above shortcomings, the present invention provides a method for factory breeding and facility culture of largemouth bass, which solves the problems of slow growth, low survival rate, high deformity rate of fry in the seedling cultivation stage and low efficiency of adult fish cultivation. The seedling cultivation method of the present invention can obtain healthy fry with uniform growth, uniform size and strong stress resistance, and improves the survival rate and growth rate of adult fish cultivation. The specific technical scheme is as follows:

[0006] A method for factory breeding and facility culture of largemouth black bass includes parent fish breeding, seed hatching, seed cultivation and adult fish culture. The seed cultivation is to transfer newly hatched largemouth black bass into a culture workshop with a cultivation pool, and cultivate the seed in darkness. The cultivation pool is circular with a diameter of 1m to 1.5m and a height of 0.8m to 1m. Each cultivation pool is respectively provided with an independent water inlet and water outlet system, and is equipped with a water pusher, a light control device, a temperature control device and an oxygenation device. The specific steps are as follows:

[0007] (1) Feeding: The cultivation density of the largemouth bass is 60,000 to 100,000 per m 3 , using the pretreated Artemia as the starter bait, feeding 40g-50g of the pretreated Artemia larvae per 100,000 water flowers per day, feeding once every 3h-4h, and then increasing the pretreated Artemia larvae by 2g-4g per day, feeding the pretreated Artemia larvae and rotifers on the 4th to 8th day, gradually increasing the proportion of rotifers every day, and feeding all rotifers after the 8th day;

[0008] The pretreatment method of the Artemia is as follows: the newly hatched Artemia is cultured in salt water with a salinity of 20%-40% for 1-2 hours, then transferred to salt water with a salinity of 10%-18% for 1-2 hours, then transferred to salt water with a salinity of 1%-8% for 1-2 hours, then transferred to salt water with a salinity of 0.1-0.5% for further culturing for 1-2 hours, and finally transferred to fresh water for culturing for 1-2 hours, thereby obtaining the pretreated Artemia;

[0009] (2) Feed conversion acclimatization: Feed conversion acclimatization starts on the 9th to 11th day, and the acclimatization period is 7 to 10 days. On the first day of acclimatization, 90% rotifers and 10% artificial compound feed are mixed and fed. Subsequently, the proportion of rotifers is gradually reduced and the proportion of artificial compound feed is increased every day until the seedlings are fully adapted to the artificial compound feed;

[0010] The artificial compound feed is firstly subjected to fermentation treatment before feeding, and the fermentation treatment comprises the following steps: feeding healthy adult largemouth black bass with the artificial compound feed, taking the intestines containing chyme segments of the adult fish after feeding for one week, drying them in the dark at 4-15°C, crushing them, mixing the powder with the artificial compound feed at a weight ratio of 1:(100-200), adjusting the humidity to 60-70%, fermenting them at 25-35°C for 5-10h, sterilizing, drying, and preparing particles of a required size, thereby obtaining the artificial compound feed after fermentation treatment.

[0011] Furthermore, the broodstock breeding is as follows: healthy largemouth black bass over 1 year old and weighing 0.5-0.8 kg / tail are selected as broodstock, and the male-female ratio is 1.0-1.5:1. The water temperature during pairing is 22°C-25°C. On the second day after pairing, fish nests are placed in the pairing pond, 1.5m-2.0m away from the shore, and the fish nests are spaced 1-2.0m apart. The fish nests are checked daily, and eggs on the fish nests are collected in time and moved into an indoor hatching pool for hatching.

[0012] Furthermore, the seedling incubation: the eggs are placed in an incubation pond with an area of ​​10㎡ to 30㎡ and a depth of 0.5m to 1.0m for incubation, the water temperature is maintained at 22℃ to 25℃, the water temperature change during the incubation period is <1℃ / d, the dissolved oxygen is maintained at 6mg / L to 8mg / L during the incubation process, the pH value of the water body is maintained at 7.0 to 8.0, and the hatching density of fertilized eggs is 3 to 5 fish nests / ㎡.

[0013] Furthermore, during the transition feeding domestication process, fixed-position light enticement, flowing water stimulation and sound knocking are used each time feeding to allow the domesticated seedlings to form conditioned reflexes to ingest food, and the light enticement, flowing water stimulation and sound knocking are carried out simultaneously; the light intensity of the light changes from weak to strong, and the light intensity on the 1st to 3rd day of domestication is 500-800Lx, the light intensity on the 4th to 6th day of domestication is 900-1000Lx, and the light intensity on the 7th to 10th day of domestication is 1200-1300Lx; the flowing water stimulation is to use a water pump to spray the original pond water into the pond to produce flowing water sound and flowing water.

[0014] Furthermore, the seedling cultivation also includes screening the seedlings at least once a week and cultivating the seedlings according to the same size specification.

[0015] Furthermore, the seedling cultivation also includes water quality regulation and management: before the largemouth black bass seedlings are 1.5 cm in total length, the water is changed once a day, and the water change amount is 100%; after the seedlings are 1.5 cm in total length, the water is changed 3 to 4 times a day, and the water change amount is 100%. The cultivation pond is continuously oxygenated, sewage is sucked out once a day, and leftover bait and dead fish are removed, and records of the growth, feeding, and water quality of the seedlings are kept.

[0016] Furthermore, the adult fish farming is pond engineered recirculating aquaculture: seedlings that are fully adapted to artificial compound feeds are placed in an engineered recirculating aquaculture system for farming, 20,000 to 30,000 seedlings are stocked in each flow channel, and special compound feed for largemouth black bass is fed every day, the special compound feed has a protein content of more than 45%, and is fed 2 to 3 times a day, with a daily feeding rate of 2% to 5%; the transparency of the aquaculture water body is maintained at 20 cm to 35 cm, the pH value is regulated between 7.0 and 8.5, and the dissolved oxygen is ≧5 mg / L; 1 h to 2 h after each feeding, the sewage suction pump is turned on to remove feces and residual bait.

[0017] The engineered recirculating aquaculture system is shown in patent CN202322033982.1 applied for by the applicant. A largemouth black bass engineered recirculating aquaculture ecological aquaculture system, the main facilities of which are: one water flow trough for every 6667 m2 of pond area, the water flow trough is generally a brick-concrete structure, 20m to 25m long, 5m to 8m wide, and 2.2m to 2.5m deep, and is respectively composed of a water pushing area, a breeding area, and a sewage collection area. Each area is separated by a barrier net, and each water flow trough is equipped with a set of 2.2kW water pushing and oxygenation equipment with an air output greater than 140m3 / h, and every 2 to 3 water flow troughs are equipped with a set of 1.5kW to 3kW microporous aeration and oxygenation equipment, and the oxygenation air supply should be greater than 30m3 / h, and a generator set matching the power consumption of the water flow trough is provided.

[0018] The supporting facilities are as follows: the sewage collection area of ​​the water flow trough is partitioned with a dense net in the vertical direction, and the length of the partition exceeds half of the center line of the pond; waterwheel-type aerators are installed at the four corners of the pond outside the water flow trough, and the number of aerators is adjusted according to actual breeding conditions; a purification area is set up outside the water flow trough, in which aquatic plants such as water spinach, elodea, water hyacinth, and elodea are planted, and the planting area accounts for 50% to 80% of the total pond area.

[0019] Furthermore, the fish farming is land-based round pond farming: the seedlings that are fully adapted to the artificial compound feed are placed in the land-based round pond for farming. Before the seedlings are released, it is ensured that the farming equipment in the land-based round pond is in good operation; large-sized largemouth black bass with a specification of 10g / tail to 30g / tail are selected for farming, and the stocking density is 30 tails / m 3 ~50 / m 3, the daily feeding rate is 2% to 6%. When the water temperature is 22℃ to 25℃, feed at 5% to 6%, when the water temperature is 16℃ to 21℃, feed at 2% to 3%, and when the water temperature is 26℃ to 30℃, feed at 3% to 4%. In the juvenile stage, the protein content in the feed is required to be 45% to 50%, and the fat content is 12% to 15%, and feeding is 3 to 4 times a day; in the adult stage, the protein content in the feed is required to be 40% to 45%, and the fat content is 6% to 10%, and feeding is 2 to 3 times a day; the specific feeding frequency and time can be adjusted according to the weather, water temperature and feeding conditions, and it is advisable to finish eating in 1 hour; during the breeding process, keep the water pH value at 6.5 to 8.5, the dissolved oxygen at more than 6mg / L, and the ammonia nitrogen content shall not exceed 0.05mg / L; after 1 hour of feeding, the water flow circulation is promoted by the power and suction filter device to filter the residual bait and feces in the water.

[0020] The land-based circular pond has a diameter of 6m to 10m and a depth of 1.5m to 2m, with a diameter-to-depth ratio maintained at 3:1 to 6:1. The land-based circular pond is equipped with oxygenation equipment, a circulating water pump, and a microfilter. These circulating equipment can maintain the water body in a swirling state, promote the exchange of upper and lower layers of the pond water, make the dissolved oxygen, temperature, etc. evenly distributed, and effectively improve the breeding level.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1. The present invention solves the problems of slow growth, low survival rate, high deformity rate of fry in the seed cultivation stage and low efficiency of adult fish cultivation by a series of technical means such as Artemia pretreatment, artificial compound feed fermentation treatment, light intensity setting and adult fish facility cultivation. The seed cultivation method of the present invention can obtain healthy fry with uniform growth, uniform size and strong stress resistance, and improves the survival rate and growth rate of adult fish cultivation.

[0023] 2. The present invention pre-treats newly hatched Artemia worms, i.e., gradually reduces the salinity of the water for breeding, thereby improving the adaptability of Artemia worms in fresh water, prolonging their survival time in fresh water, and improving their vitality in fresh water, so that the fry can fully ingest Artemia worms, thereby improving the survival rate of the fry.

[0024] 3. When the fry are acclimated by the present invention, a fermentation treatment is first performed before feeding the artificial formula feed. The fermentation treatment is performed by using the intestines containing chyme segments of healthy adult fish fed with the artificial formula feed for fermentation. The intestines containing chyme segments contain a large number of beneficial digestive bacteria, which can convert the protein in the artificial formula feed into polypeptides and amino acids that are more conducive to digestion and absorption, thereby reducing the indigestion of the fry after eating the feed, improving the feeding efficiency, and thus reducing the mortality rate and deformity rate.

[0025] 4. The present invention adopts fixed-position light luring, running water stimulation and sound knocking in the process of feeding each time, which can make the domesticated seedlings form conditioned reflexes, and carry out centralized feeding at fixed positions to form the habit of centralized feeding, so that there will be no scattered feeding in the adult fish breeding stage, so that the fish grow neatly and uniform in size, and the situation of cannibalism is reduced. At the same time, the light of the lamplight is set to change from weak to strong, which reduces the situation that the early stage of the fry's weak stress resistance leads to a strong stress reaction to strong light. With the growth of the fry, the stress resistance becomes stronger and stronger, and the light can be gradually strengthened to increase the feeding vitality and improve the survival rate of the fry.

[0026] 5. The adult fish farming of the present invention adopts engineered circulating water farming. Compared with traditional pond farming, it can ensure that the dissolved oxygen in the water is stable at 5mg / L-8mg / L, improve the feeding rate and growth rate of largemouth bass, reduce the feeding cost and fishing cost of largemouth bass, and greatly increase the production per unit area of ​​farming. The aquaculture water is recycled after sewage collection, filtration and purification, and the recycling rate of water resources can reach more than 90%, which greatly reduces the waste of water resources and has a significant effect of reducing costs and increasing efficiency.

[0027] 6. The adult fish farming of the present invention adopts land-based circular pond farming, which has a higher space utilization rate compared with traditional pond farming. It can be flexibly arranged according to the site and local conditions to achieve large-scale cluster farming. Land-based circular pond farming can effectively isolate external pathogens and significantly reduce the risk of disease occurrence; it can also create a stable and comfortable growth environment for largemouth black seabass through precise water quality control technologies, such as biological filtration, aeration and oxygenation, temperature regulation, etc., and significantly improve the survival rate and growth rate of farming. In addition, the land-based circular pond farming model has a high degree of automation and intelligence. With the help of sensors, monitoring equipment and intelligent control systems, farmers can remotely grasp the farming dynamics of largemouth black seabass in real time, adjust farming strategies in time, greatly save labor costs, and significantly improve management efficiency. DETAILED DESCRIPTION

[0028] The specific embodiments of the present invention are described in detail below, but it should be understood that the protection scope of the present invention is not limited by the specific embodiments.

[0029] Example 1

[0030] A method for factory breeding and facility culture of largemouth bass comprises the following steps:

[0031] (1) Broodstock breeding: healthy largemouth bass over 1 year old and weighing 0.5 kg / tail were selected as broodstock and paired at a female-to-male ratio of 1.0 to 1.5. The water temperature during pairing was 22°C. On the second day after pairing, fish nests were placed in the pairing pond, 1.5 m away from the shore and 1 m apart. The fish nests were checked daily. Any eggs found on the nests were collected in time and moved to an indoor hatchery for hatching.

[0032] (2) Seedling hatching: The eggs were placed in a hatching pond with an area of ​​10 m2 and a depth of 0.5 m for hatching. The water temperature was maintained at 22°C. The water temperature change during the hatching period was less than 1°C / day. The dissolved oxygen was maintained at 6 mg / L during the hatching process. The pH value of the water body was maintained at 7.0. The hatching density of fertilized eggs was 3 fish nests / m2.

[0033] (3) Seedling cultivation: The newly hatched largemouth black bass are transferred to a cultivation workshop equipped with a cultivation pool for seedling cultivation in darkness. The cultivation pool is circular, 1 m in diameter and 0.8 m in height. Each cultivation pool is equipped with an independent water inlet and outlet system, and is equipped with a water pusher, light control equipment, temperature control equipment and oxygen enrichment equipment. The specific steps are as follows:

[0034] A. Feeding: The breeding density of the largemouth bass is 60,000 / m 3 , use pretreated Artemia as the starter bait, feed 40g of pretreated Artemia larvae for every 100,000 water flowers per day, feed once every 3 hours, and then increase the amount of pretreated Artemia larvae by 2g every day, feed pretreated Artemia larvae and rotifers from the 4th to the 8th day, gradually increase the amount of rotifers by 20% every day, and feed only rotifers after the 8th day;

[0035] The pretreatment method of Artemia is as follows: the newly hatched Artemia is cultured in salt water with a salinity of 20% for 1 hour, then transferred to salt water with a salinity of 10% for 1 hour, then transferred to salt water with a salinity of 1% for 1 hour, then transferred to salt water with a salinity of 0.1% for further culturing for 1 hour, and finally transferred to fresh water for culturing for 1 hour, thus obtaining the pretreated Artemia;

[0036] B. Feed conversion acclimatization: Feed conversion acclimatization starts on the 9th day, and the acclimatization period is 7 to 10 days. On the first day of acclimatization, 90% rotifers and 10% artificial compound feed are mixed and fed. Subsequently, the proportion of rotifers is gradually reduced by 20% every day, and the proportion of artificial compound feed is increased until the seedlings are fully adapted to the artificial compound feed;

[0037] The artificial compound feed is firstly subjected to fermentation treatment before feeding, and the fermentation treatment comprises the following steps: feeding healthy adult largemouth black bass with the artificial compound feed, taking the intestines containing chyme segments of the adult fish after feeding for one week, drying them in the dark at 4°C, crushing them, mixing the powder with the artificial compound feed at a weight ratio of 1:100, adjusting the humidity to 60%, fermenting them at 25°C for 5 hours, sterilizing, drying, and preparing particles of a required size, thereby obtaining the artificial compound feed after fermentation treatment.

[0038] During the transition to feeding and domestication process, fixed-position light enticement, running water stimulation and sound knocking are used each time feeding to allow the domesticated seedlings to form conditioned reflexes to feed, and the light enticement, running water stimulation and sound knocking are carried out simultaneously; the light intensity of the light changes from weak to strong, and the light intensity is 500Lx on the 1st to 3rd day of domestication, 900Lx on the 4th to 6th day of domestication, and 1200Lx on the 7th to 10th day of domestication; the running water stimulation is to use a water pump to spray the original pond water into the pond to produce running water sounds and flowing water.

[0039] C. Daily management: Use sieves with different mesh sizes to separate seedlings of different sizes once a week, and raise seedlings of similar sizes together.

[0040] D. Water quality regulation and management: Before the largemouth black bass seedlings are 1.5 cm in length, change the water once a day with a 100% water replacement rate. After the seedlings are 1.5 cm in length, change the water three times a day with a 100% water replacement rate. Keep continuous oxygenation in the breeding pond, vacuum the sewage once a day, remove leftover bait and dead fish, and keep records of the seedlings' growth, feeding, and water quality.

[0041] (4) Adult fish culture is pond engineering recirculating aquaculture: seedlings that are fully adapted to artificial compound feeds are placed in an engineering recirculating aquaculture system for culture, with 20,000 seedlings being stocked in each flow channel and fed with special compound feed for largemouth bass every day. The special compound feed has a protein content of more than 45%, and is fed twice a day with a daily feeding rate of 2%. The transparency of the aquaculture water body is maintained at 20 cm, the pH value is regulated at 7.0, and the dissolved oxygen is ≧5 mg / L; 1 hour after each feeding, the sewage pump is turned on to remove feces and leftover bait.

[0042] The engineered circulating water aquaculture system can be found in the patent CN202322033982.1 that the applicant has applied for. A largemouth bass engineered circulating water ecological aquaculture system, the main facilities of which are: one water flow trough for every 6667 square meters of pond area, the water flow trough is generally a brick-concrete structure, 20 meters long, 5 meters wide, and 2.2 meters deep, consisting of a water push area, a breeding area, and a sewage collection area, each of which is separated by a fence. Each water flow trough is equipped with a 2.2kW water push aeration equipment, and the gas output is greater than 140m 3 / h, each two water troughs are equipped with a set of 1.5kW microporous aeration and oxygenation equipment, and the oxygen supply volume should be greater than 30m 3 / h, and is equipped with a generator set that matches the power consumption of the water trough.

[0043] The supporting facilities are as follows: the sewage collection area of ​​the water trough is partitioned with a dense net in the vertical direction, and the length of the partition exceeds half of the center line of the pond; waterwheel-type aerators are installed at the four corners of the pond outside the water trough, and the number of aerators is adjusted according to actual breeding conditions; a purification area is set up outside the water trough, in which aquatic plants such as water spinach, elodea, water hyacinth, and elodea are planted, and the planting area accounts for 50% of the total pond area.

[0044] Example 2

[0045] A method for factory breeding and facility culture of largemouth bass comprises the following steps:

[0046] (1) Broodstock breeding: healthy largemouth bass over 1 year old and weighing 0.8 kg / tail were selected as broodstock and paired at a female-to-male ratio of 1.0 to 1. The water temperature during pairing was 25°C. On the second day after pairing, fish nests were placed in the pairing pond, 2.0 m away from the shore and 2.0 m apart. The fish nests were checked daily and any eggs on the nests were collected in time and moved to an indoor hatchery for hatching.

[0047] (2) Seedling hatching: The eggs were placed in a hatching pond with an area of ​​30 m2 and a depth of 1.0 m for hatching. The water temperature was maintained at 25°C. The water temperature change during the hatching period was less than 1°C / d. The dissolved oxygen was maintained at 8 mg / L during the hatching process. The pH value of the water was maintained at 8.0. The hatching density of fertilized eggs was 5 fish nests / m2.

[0048] (3) Seedling cultivation: The newly hatched largemouth black bass are transferred to a cultivation workshop equipped with a cultivation pool for seedling cultivation in darkness. The cultivation pool is circular, 1.5 m in diameter and 1 m in height. Each cultivation pool is equipped with an independent water inlet and outlet system, and is equipped with a water pusher, light control equipment, temperature control equipment and oxygen enrichment equipment. The specific steps are as follows:

[0049] A. Feeding: The cultivation density of the largemouth bass is 100,000 / m 3 , use pretreated Artemia as the starter bait, feed 50g of pretreated Artemia larvae for every 100,000 water flowers per day, feed once every 4 hours, and then increase the amount of pretreated Artemia larvae by 4g every day. From the 4th to the 9th day, feed pretreated Artemia larvae and rotifers, gradually increase the amount of rotifers by 20% every day, and feed only rotifers after the 9th day;

[0050] The pretreatment method of Artemia is as follows: the newly hatched Artemia is cultured in salt water with a salinity of 40% for 2 hours, then transferred to salt water with a salinity of 18% for 2 hours, then transferred to salt water with a salinity of 8% for 2 hours, then transferred to salt water with a salinity of 0.5% for further culturing for 2 hours, and finally transferred to fresh water for culturing for 2 hours, thereby obtaining the pretreated Artemia;

[0051] B. Feed conversion acclimatization: Feed conversion acclimatization starts on the 10th day, and the acclimatization period is 7 to 10 days. On the first day of acclimatization, 90% rotifers and 10% artificial compound feed are mixed and fed. Subsequently, the proportion of rotifers is gradually reduced by 20% every day, and the proportion of artificial compound feed is increased until the seedlings are fully adapted to the artificial compound feed;

[0052] The artificial compound feed is firstly subjected to fermentation treatment before feeding, and the fermentation treatment comprises the following steps: feeding healthy adult largemouth black bass with the artificial compound feed, taking the intestines containing chyme segments of the adult fish after feeding for one week, drying them in the dark at 15°C, crushing them, mixing the powder with the artificial compound feed at a weight ratio of 1:200, adjusting the humidity to 70%, fermenting them at 35°C for 10 hours, sterilizing, drying, and preparing particles of a required size, thereby obtaining the artificial compound feed after fermentation treatment.

[0053] During the transition to feeding and domestication process, fixed-position light enticement, running water stimulation and sound knocking are used each time feeding to allow the domesticated seedlings to form conditioned reflexes to feed, and the light enticement, running water stimulation and sound knocking are carried out simultaneously; the light of the light changes from weak to strong, and the light intensity is 800Lx on the 1st to 3rd day of domestication, 1000Lx on the 4th to 6th day of domestication, and 1300Lx on the 7th to 10th day of domestication; the running water stimulation is to use a water pump to spray the original pond water into the pond to produce running water sounds and flowing water.

[0054] C. Daily management: Use sieves with different mesh sizes to separate seedlings of different sizes once a week, and raise seedlings of similar sizes together.

[0055] D. Water quality regulation and management: Before the largemouth black bass seedlings are 1.5 cm in length, change the water once a day with a 100% water replacement rate. After the seedlings are 1.5 cm in length, change the water four times a day with a 100% water replacement rate. Keep continuous oxygenation in the breeding pond, vacuum the sewage once a day, remove leftover bait and dead fish, and keep records of the seedlings' growth, feeding, and water quality.

[0056] (4) Adult fish culture is pond engineering recirculating aquaculture: seedlings that are fully adapted to artificial compound feeds are placed in an engineering recirculating aquaculture system for culture, 30,000 seedlings are stocked in each flow channel, and they are fed with special compound feed for largemouth bass every day. The protein content of the special compound feed is more than 45%, and the feed is fed three times a day with a daily feeding rate of 5%. The transparency of the aquaculture water body is maintained at 35 cm, the pH value is regulated at 8.5, and the dissolved oxygen is ≧5 mg / L; 2 hours after each feeding, the sewage pump is turned on to remove feces and leftover bait.

[0057] The engineered circulating water aquaculture system can be found in the patent CN202322033982.1 that the applicant has applied for. A largemouth bass engineered circulating water ecological aquaculture system, the main facilities of which are: one water flow trough for every 6667 square meters of pond area, the water flow trough is generally a brick-concrete structure, 25 meters long, 8 meters wide, and 2.5 meters deep, consisting of a water push area, a breeding area, and a sewage collection area, each area is separated by a fence, and each water flow trough is equipped with a 2.2kW water push aeration equipment, and the gas output is greater than 140m 3 / h, each of the three water troughs is equipped with a set of 3kW microporous aeration and oxygenation equipment, and the oxygen supply volume should be greater than 30m 3 / h, and is equipped with a generator set that matches the power consumption of the water trough.

[0058] The supporting facilities are as follows: the sewage collection area of ​​the water trough is partitioned with a dense net in the vertical direction, and the length of the partition exceeds half of the center line of the pond; waterwheel-type aerators are installed at the four corners of the pond outside the water trough, and the number of aerators is adjusted according to actual breeding conditions; a purification area is set up outside the water trough, in which aquatic plants such as water spinach, elodea, water hyacinth, and elodea are planted, and the planting area accounts for 80% of the total pond area.

[0059] Example 3

[0060] A method for factory breeding and facility culture of largemouth bass comprises the following steps:

[0061] (1) Broodstock breeding: healthy largemouth bass over 1 year old and weighing 0.2 kg / tail were selected as broodstock and paired at a female-to-male ratio of 1.0 to 1. The water temperature during pairing was 23°C. On the second day after pairing, fish nests were placed in the pairing pond, 2.0 m away from the shore and 1 m apart. The fish nests were checked daily and any eggs on the nests were collected in time and moved to an indoor hatchery for hatching.

[0062] (2) Seedling hatching: The eggs were placed in a hatching pond with an area of ​​30 m2 and a depth of 0.5 mm for hatching. The water temperature was maintained at 24°C. The water temperature change during the hatching period was less than 1°C / d. The dissolved oxygen was maintained at 7 mg / L during the hatching process. The pH value of the water body was maintained at 7.5. The hatching density of fertilized eggs was 4 fish nests / m2.

[0063] (3) Seedling cultivation: The newly hatched largemouth bass are transferred to a cultivation workshop equipped with a cultivation pool for seedling cultivation in darkness. The cultivation pool is circular, 1 m in diameter and 1 m in height. Each cultivation pool is equipped with an independent water inlet and outlet system, and is equipped with a water pusher, light control equipment, temperature control equipment and oxygen enrichment equipment. The specific steps are as follows:

[0064] A. Feeding: The cultivation density of the largemouth bass is 80,000 / m 3, use pretreated Artemia as the starter bait, feed 45g of pretreated Artemia larvae for every 100,000 water flowers per day, feed once every 4 hours, and then increase the pretreated Artemia larvae by 3g every day, feed pretreated Artemia larvae and rotifers from the 4th to the 10th day, gradually increase the rotifers by 20% every day, and feed all rotifers after the 10th day;

[0065] The pretreatment method of Artemia is as follows: the newly hatched Artemia is cultured in salt water with a salinity of 30% for 1 hour, then transferred to salt water with a salinity of 15% for 1 hour, then transferred to salt water with a salinity of 5% for 2 hours, then transferred to salt water with a salinity of 0.4% for further culturing for 2 hours, and finally transferred to fresh water for culturing for 2 hours, thus obtaining the pretreated Artemia;

[0066] B. Feed conversion acclimatization: Feed conversion acclimatization starts on the 11th day, and the acclimatization period is 7 to 10 days. On the first day of acclimatization, 90% rotifers and 10% artificial compound feed are mixed and fed. Subsequently, the proportion of rotifers is gradually reduced by 20% every day, and the proportion of artificial compound feed is increased until the seedlings are fully adapted to the artificial compound feed;

[0067] The artificial compound feed is firstly subjected to fermentation treatment before feeding, and the fermentation treatment comprises: feeding healthy adult largemouth black bass with the artificial compound feed, taking the intestines containing chyme segments of the adult fish after feeding for one week, drying them in the dark at 10°C, crushing them, mixing the powder with the artificial compound feed at a weight ratio of 1:150, adjusting the humidity to 65%, fermenting them at 30°C for 8h, sterilizing, drying, and preparing particles of a required size, thereby obtaining the artificial compound feed after fermentation treatment.

[0068] During the transition to feeding and domestication process, fixed-position light enticement, running water stimulation and sound knocking are used each time feeding to allow the domesticated seedlings to form conditioned reflexes to feed, and the light enticement, running water stimulation and sound knocking are carried out simultaneously; the light intensity of the light changes from weak to strong, and the light intensity is 600Lx on the 1st to 3rd day of domestication, 950Lx on the 4th to 6th day of domestication, and 1200Lx on the 7th to 10th day of domestication; the running water stimulation is to use a water pump to spray the original pond water into the pond to produce running water sounds and flowing water.

[0069] C. Daily management: Use sieves with different mesh sizes to separate seedlings of different sizes once a week, and raise seedlings of similar sizes together.

[0070] D. Water quality regulation and management: Before the largemouth black bass seedlings are 1.5 cm in length, change the water once a day with a 100% water replacement rate. After the seedlings are 1.5 cm in length, change the water three times a day with a 100% water replacement rate. Keep continuous oxygenation in the breeding pond, vacuum the sewage once a day, remove leftover bait and dead fish, and keep records of the seedlings' growth, feeding, and water quality.

[0071] (4) Adult fish culture is land-based round pond culture: seedlings that are fully adapted to artificial compound feed are placed in land-based round ponds for culture. Before stocking the seedlings, ensure that the culture equipment in the land-based round pond is in good operation; select large-sized largemouth black bass with a specification of 30g / tail for culture, and the stocking density is 40 / m 3 , daily feeding rate is 5%, when the water temperature is 24℃, feed at 6%, when the water temperature is 20℃, feed at 3%, when the water temperature is 30℃, feed at 4%; in the juvenile stage, the protein content in the feed is required to be 50%, the fat content is 15%, and feeding is 3 times a day; in the adult stage, the protein content in the feed is required to be 40%, the fat content is 10%, and feeding is 3 times a day; the specific feeding number and time can be adjusted according to the weather, water temperature and feeding conditions, and it is advisable to finish eating in 1 hour; during the breeding process, maintain the water pH value of 6.5, the dissolved oxygen above 6mg / L, and the ammonia nitrogen content shall not exceed 0.05mg / L; after 1 hour of feeding, the water circulation is driven by power and suction filtration devices to filter out the residual bait and feces in the water.

[0072] The diameter of the land-based circular pond is 6m, the depth is 2m, and the diameter-to-depth ratio is maintained at 3:1. The land-based circular pond is equipped with oxygenation equipment, a circulating water pump, and a microfilter. These circulating equipment can maintain the water body in a vortex state, promote the exchange of upper and lower layers of the pond water, make the dissolved oxygen, temperature, etc. evenly distributed, and effectively improve the breeding level.

[0073] The survival rate, deformity rate, superoxide dismutase (SOD) content, lysozyme (Lysozyme) content of the fry in the seed cultivation stage of Examples 1 to 3, and the specific growth rate of the largemouth bass in the adult fish breeding stage were measured respectively, and the average values ​​of each index were taken. The results are shown in Table 1:

[0074] After the transition to food training in the fry rearing stage, five fry were randomly selected from each rearing pond, and blood was drawn for biochemical analysis using commercial kits (Nanjing Jiancheng Biological, China) to determine the serum SOD content and lysozyme content.

[0075] The specific growth rate was determined by selecting largemouth bass in the adult culture stage, and the specific growth rate (%) = (ln final weight - ln initial weight) / culture time * 100.

[0076] Table 1

[0077]

[0078] As shown in Table 1, the breeding method of the present invention can increase the survival rate of fry to 63-66% in the seed breeding stage, reduce the deformity rate to 3-4%, increase the specific growth rate in the adult fish breeding stage to more than 35%, and increase the SOD content and lysozyme content of fry, thereby improving the anti-stress performance and immunity of fry.

[0079] Comparative Example 1: Artemia was not pretreated before feeding, and other breeding methods were consistent with those in Example 1.

[0080] Comparative Example 2: During the transition to feeding domestication, the artificial compound feed was not fermented, and other breeding methods were consistent with those in Example 1.

[0081] Comparative Example 3: During the feeding acclimation process, the light intensity of the light luring during feeding was 1200Lx, and other breeding methods were consistent with Example 1.

[0082] Comparative Example 4: During the feeding acclimation process, only light was used for each feeding, without water flow stimulation or sound knocking. Other breeding methods were consistent with those in Example 1.

[0083] The survival rate, deformity rate, superoxide dismutase (SOD) content, lysozyme content of the fry in the seed cultivation stage of Comparative Examples 1 to Comparative Examples 4, as well as the specific growth rate of the largemouth bass in the adult fish breeding stage were measured respectively, and the average values ​​of each index were taken. The results are shown in Table 2:

[0084] Table 2

[0085]

[0086] From Table 2, we can see that the survival rate of fry can be increased by 33% and the deformity rate can be reduced by 38.8% after pretreatment with Artemia, while the survival rate of fry can be increased by 50% and the deformity rate can be reduced by 53.9% after fermentation of artificial compound feed. At the same time, Artemia pretreatment, fermentation of artificial compound feed and light intensity setting can improve the anti-stress performance and immunity of fry to a certain extent.

[0087] In summary, the present invention solves the problems of slow growth, low survival rate, high deformity rate of fry in the seedling cultivation stage and low efficiency of adult fish cultivation through a series of technical means such as Artemia pretreatment, artificial compound feed fermentation treatment, light intensity setting and adult fish facility cultivation. The seedling cultivation method of the present invention can obtain healthy fry with uniform growth, uniform size and strong stress resistance, and improves the survival rate and growth rate of adult fish cultivation.

[0088] The foregoing description of specific exemplary embodiments of the present invention is for the purpose of illustration and demonstration. These descriptions are not intended to limit the present invention to the precise form disclosed, and it is clear that many changes and variations can be made based on the above teachings. The purpose of selecting and describing the exemplary embodiments is to explain the specific principles of the present invention and its practical application, so that those skilled in the art can realize and utilize various different exemplary embodiments of the present invention and various different selections and changes. The scope of the present invention is intended to be limited by the claims and their equivalents.

Claims

1. A method for factory breeding and facility culture of largemouth bass, comprising parent fish breeding, seedling hatching, seedling cultivation and adult fish culture, characterized in that: The seedling cultivation is to transfer the newly hatched largemouth bass into a cultivation workshop equipped with a cultivation pool, and cultivate the seedlings in a dark environment. The specific steps are as follows: (1) Feeding: The cultivation density of the largemouth bass is 60,000 to 100,000 per m 3 , using the pretreated Artemia as the starter bait, feeding 40g-50g of the pretreated Artemia larvae per 100,000 water flowers per day, feeding once every 3h-4h, and then increasing the pretreated Artemia larvae by 2g-4g per day, feeding the pretreated Artemia larvae and rotifers on the 4th to 8th day, gradually increasing the proportion of rotifers every day, and feeding all rotifers after the 8th day; The pretreatment method of the Artemia is as follows: the newly hatched Artemia is cultured in salt water with a salinity of 20%-40% for 1-2 hours, then transferred to salt water with a salinity of 10%-18% for 1-2 hours, then transferred to salt water with a salinity of 1%-8% for 1-2 hours, then transferred to salt water with a salinity of 0.1-0.5% for further culturing for 1-2 hours, and finally transferred to fresh water for culturing for 1-2 hours, thereby obtaining the pretreated Artemia; (2) Feed conversion acclimatization: Feed conversion acclimatization starts on the 9th to 11th day, and the acclimatization period is 7 to 10 days. On the first day of acclimatization, 90% rotifers and 10% artificial compound feed are mixed and fed. Subsequently, the proportion of rotifers is gradually reduced and the proportion of artificial compound feed is increased every day until the seedlings are fully adapted to the artificial compound feed; The artificial compound feed is firstly subjected to fermentation treatment before feeding, and the fermentation treatment comprises the following steps: feeding healthy adult largemouth black bass with the artificial compound feed, taking the intestines containing chyme segments of the adult fish after feeding for one week, drying them in the dark at 4-15°C, crushing them, mixing the powder with the artificial compound feed at a weight ratio of 1:(100-200), adjusting the humidity to 60-70%, fermenting them at 25-35°C for 5-10h, sterilizing, drying, and preparing particles of a required size, thereby obtaining the artificial compound feed after fermentation treatment.

2. The method for factory breeding and facility culture of largemouth bass according to claim 1, characterized in that: The broodstock breeding is as follows: healthy largemouth black bass over 1 year old and weighing 0.5-0.8 kg / tail are selected as broodstock, and the male-female ratio is 1.0-1.5:

1. The water temperature during the pairing is 22°C-25°C. On the second day after the pairing, fish nests are placed in the pairing pond, the fish nests are 1.5m-2.0m away from the shore, and the fish nests are spaced 1-2.0m apart. The fish nests are checked daily, and eggs on the fish nests are collected in time and moved into an indoor hatching pool for hatching.

3. The method for factory breeding and facility culture of largemouth bass according to claim 1, characterized in that: The seedling hatching method comprises placing the eggs into a hatching pool for hatching, maintaining the water temperature at 22°C to 25°C, the water temperature variation during the hatching period being <1°C / d, the dissolved oxygen being maintained at 6mg / L to 8mg / L during the hatching process, the water pH being maintained at 7.0 to 8.0, and the hatching density of the fertilized eggs being 3 to 5 fish nests / ㎡.

4. The method for factory breeding and facility culture of largemouth bass according to claim 1, characterized in that: During the transition feeding domestication process, fixed-position light enticement, running water stimulation and sound knocking are used each time feeding to allow the domesticated seedlings to form conditioned reflexes to ingest food, and the light enticement, running water stimulation and sound knocking are carried out simultaneously; the light intensity of the light changes from weak to strong, and the light intensity on the 1st to 3rd day of domestication is 500-800Lx, the light intensity on the 4th to 6th day of domestication is 900-1000Lx, and the light intensity on the 7th to 10th day of domestication is 1200-1300Lx; the running water stimulation is to use a water pump to spray the original pond water into the pond to produce running water sound and flowing water.

5. The method for factory breeding and facility culture of largemouth bass according to claim 1, characterized in that: The seedling cultivation also includes screening the seedlings at least once a week and cultivating the seedlings according to the same size specifications.

6. The method for factory breeding and facility culture of largemouth bass according to claim 1, characterized in that: The seedling cultivation also includes water quality regulation and management: before the largemouth black bass seedlings are 1.5 cm in total length, the water is changed once a day, with a water change rate of 100%; after the seedlings are 1.5 cm in total length, the water is changed 3 to 4 times a day, with a water change rate of 100%. The cultivation pond is continuously oxygenated, sewage is sucked out once a day, and leftover bait and dead fish are removed, and records of the growth, feeding, and water quality of the seedlings are kept.

7. The method for factory breeding and facility culture of largemouth bass according to claim 1, characterized in that: The adult fish farming is pond engineering recirculating water farming: seedlings that are fully adapted to artificial compound feeds are placed in the engineering recirculating water farming system for farming, 20,000 to 30,000 seedlings are stocked in each flow channel, and special compound feeds for largemouth black bass are fed every day, wherein the protein content of the special compound feed is more than 45%, and the feed is fed 2 to 3 times a day, with a daily feeding rate of 2% to 5%; the transparency of the farming water body is maintained at 20 cm to 35 cm, the pH value is regulated between 7.0 and 8.5, and the dissolved oxygen is ≧5 mg / L; 1 h to 2 h after each feeding, the sewage suction pump is turned on to remove feces and residual bait.

8. The method for factory breeding and facility culture of largemouth bass according to claim 1, characterized in that: The fish farming is carried out in land-based circular ponds: the seedlings fully adapted to the artificial compound feed are placed in land-based circular ponds for farming, with a stocking density of 30 fish / m 3 ~50 / m 3 , the daily feeding rate is 2% to 6%. When the water temperature is 22℃ to 25℃, feed at 5% to 6%, when the water temperature is 16℃ to 21℃, feed at 2% to 3%, and when the water temperature is 26℃ to 30℃, feed at 3% to 4%. In the juvenile stage, the protein content in the feed is required to be 45% to 50%, and the fat content is 12% to 15%, and feeding is 3 to 4 times a day; in the adult stage, the protein content in the feed is required to be 40% to 45%, and the fat content is 6% to 10%, and feeding is 2 to 3 times a day; the specific feeding frequency and time can be adjusted according to the weather, water temperature and feeding conditions, and it is advisable to finish eating in 1 hour; during the breeding process, keep the water pH value at 6.5 to 8.5, the dissolved oxygen at more than 6mg / L, and the ammonia nitrogen content shall not exceed 0.05mg / L; after 1 hour of feeding, the water flow circulation is promoted by the power and suction filter device to filter the residual bait and feces in the water.

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