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CN-122004157-A - Method for improving germplasm of crayfish on market in advance

CN122004157ACN 122004157 ACN122004157 ACN 122004157ACN-122004157-A

Abstract

A method for improving the germplasm of crayfish on the market in advance belongs to the technical field of crayfish improved variety breeding. The invention utilizes paddy field engineering, industrial hatching workshops, net cages and plastic greenhouse facilities to carry out screening and breeding in the growth stages of breeding four crayfishes in the egg-holding, young-holding and backup parents, and each stage preferably selects a certain proportion of good individuals according to target characters, thereby accelerating the aggregation of the target good characters, quickly obtaining the population with strong fertility, quick growth and early marketing, and accelerating the progress of improving the crayfish germplasm. According to the method, through the technical steps of breeding egg-holding shrimps in a paddy field, incubating young shrimp in a hatching workshop in a temperature-controlled manner, culturing the water flower seedlings in a net cage in vitro, marking the water flower seedlings in a plastic greenhouse roughly, culturing parent shrimps in a paddy field, and the like, the egg-holding shrimps, the young shrimps, the water flower seedlings, large-size shrimp seedlings and commodity shrimps can be obtained in batches in advance, so that the time for selling the commodity shrimps of the crayfish is advanced to the middle ten days of 4 months, and is advanced by more than 15 days compared with the time for selling the commodity shrimps cultured in a conventional paddy field.

Inventors

  • SONG GUANGTONG
  • BAO MING
  • SHEN LEI
  • JI SUOFEI
  • ZHU YUNFEI
  • ZHANG QINGQING
  • XU XIAONA
  • LIU BING
  • WU XIANGYU
  • WANG AIMIN
  • LI MINGYOU
  • HE JIXIANG
  • ZHANG XIAOHONG
  • WEI TAO

Assignees

  • 安徽省农业科学院水产研究所
  • 安徽春泉农业科技有限公司

Dates

Publication Date
20260512
Application Date
20260212

Claims (7)

  1. 1. A method for improving the germplasm of crayfish on the market in advance is characterized in that screening and breeding are carried out in the growth stages of breeding egg-holding crayfish, hatching young crayfish, in-vitro breeding of crayfish fries and standard and thick and backup parent breeding of the four crayfish by utilizing rice field engineering, factory hatching workshops, net cages and plastic greenhouse facilities, and according to the target characters, excellent individuals are optimized according to the selection pressure of 40-50% in each stage, the aggregation of the target excellent characters is accelerated, the colony with strong fertility and fast growth is obtained quickly, and the progress of improving the germplasm of the crayfish is accelerated.
  2. 2. The method for improving the germplasm of crayfish on the market in advance as claimed in claim 1, wherein the breeding stage of the crayfish with eggs comprises the following specific steps: (1) Rice field engineering The method comprises the steps of (1) excavating L-shaped, U-shaped or annular shrimp grooves around a paddy field, wherein the groove width is 2-3 m, the depth is 50-60 cm, the ridge height is 50-60 cm, the ridge width is 1-2 m, sub-ridges are arranged along one side of the shrimp grooves close to the field, the sub-ridges are 40-50 cm in width and 10-20 cm in height, the gradient ratio of each ridge groove is 1 (1-2), the area of each groove occupies not more than 10%, and an escape preventing net is arranged along the position 10-20 cm below the ridge surface, so that parent shrimps can make holes at the position 10-20 cm below the ridge slope, and water is conveniently added to stimulate the egg-holding shrimps to make holes; (2) Aquatic weed transplanting Transplanting 2 rows of waterweeds in the shrimp grooves in the middle of 3 months, transplanting 2 rows of waterweeds every 8-10 m on the field surface, wherein the planting distance of the waterweeds is 4-5 m, and the coverage area of the waterweeds reaches 50% in the middle of 4 months; (3) Rice planting Selecting a medium-long rice variety within 135 days of the growing period, sowing and raising seedlings in middle and late 4 months, mechanically transplanting or manually transplanting seedlings in middle and late 5 months, and finishing harvesting the rice in middle and late 9 months; (4) Parent shrimp selection and stocking Selecting excellent parents with the specification of more than 25g from the backup parent shrimps, taking healthy and active and complete attached limbs as parents by combining the backup parent shrimps for 4 months, taking the large specification as a breeding target, selecting the pressure of 40-50%, and screening the excellent parents, wherein the eliminated backup parent shrimps are sold as commercial shrimps; (5) Cultivation of parent shrimps Feeding special pellet feed (with 36% of protein content and 2-3 mm of particle size) for high-quality crayfish the next day after parent shrimps are put in, wherein the daily feeding rate is 2-4%, the feed is fed only in shrimp furrows after rice is transplanted totally Tian Touwei before rice is transplanted, the air temperature is over 30 ℃ after 7 months, the daily feeding rate is reduced to 1-2%, the air temperature is over 33 ℃, half feeding or stop feeding is reduced, a feeding table is arranged, and the feeding amount is timely adjusted according to the feeding condition; (6) Inducing propagation The method comprises the steps of transplanting rice seedlings, gradually draining water into a ditch in the middle and the last days of 5 months to induce parent shrimps to enter cavities for mating propagation, draining water into the ditch in the middle and the last days of 6 months to induce parent shrimps to enter cavities for mating propagation again after the seedlings are combined with tillering, keeping dry and wet states of the rice fields in the early stage of waxing of the rice in 8 months to induce parent shrimps to enter cavities for mating propagation, thoroughly draining field water and ditch water in the early stage of yellow ripening of the rice in the middle and the last days of 9 months to induce parent shrimps to enter cavities for spawning, insemination, egg holding and hatching; (7) Egg-holding shrimp fishing And 2 rows of flower basket ground cages are arranged along the shrimp grooves of the rice field while water is added, 1 row of flower basket ground cages are arranged along the bottom ends of the sub-banks, egg-holding shrimps are caught, and the temperature is controlled and hatched in a classified manner according to the development degree of fertilized eggs.
  3. 3. The method for improving the germplasm of crayfish on the market in advance as claimed in claim 2, wherein the incubation stage of the crayfish with eggs comprises the following specific steps: (1) Hatching facility Setting a hatching pond in a hatching room, wherein the hatching pond adopts a cement pond or a PP square pond, the hatching pond is built according to the size of a room, the single hatching pond is 10-30 m 2 and 0.8m deep, each hatching pond is provided with a water circulation treatment filtering system, an air energy or boiler heating system, a Roots blower or a vortex type oxygenation system, and a three-dimensional grid degassing filler is used as a hidden object; (2) Screening and hatching of egg-holding shrimps And (3) selecting excellent egg-holding shrimps with large egg holding capacity and no mildewed eggs from the egg-holding shrimps bred in the paddy field according to the selection pressure of 40-50%, carrying out classified pond-separating hatching according to the egg development stage, keeping the water level of a hatching pond at 50-60 cm, keeping the water temperature at 25-26 ℃ and the dissolved oxygen at more than 5mg/L, and carrying out temperature-controlled hatching for 20-30 days to obtain the high-quality young shrimp.
  4. 4. A method for improving the germplasm of a crayfish on the market in advance as claimed in claim 3, wherein the specific steps of the isolated culture of the crayfish are as follows: (1) In vitro cultivation of water flower seedlings The method comprises the steps of adopting a cement pond or a canvas pond, a net cage and a plastic greenhouse as a water flower seedling in-vitro cultivation facility, arranging an inner net cage and an outer net cage in the cement pond or the canvas pond, arranging a plastic sunlight greenhouse above the cement pond or the canvas pond, facilitating the maintenance of water temperature, avoiding the influence of rainwater on water quality and young shrimp holding, and promoting the rapid in-vitro cultivation of the water flower seedlings, wherein the net cage has the specification of 2-4 m 2 , adopting the inner net cage and the outer net cage, wherein the area of the inner net cage accounts for 70-80% of the area of the outer net cage, the mesh of the inner net cage adopts a net cage with 3-5 meshes, so that the water flower seedlings leaving a parent body can enter the outer net cage through large meshes, the mesh of the outer net cage adopts a net cage with 40-60 meshes, carrying the water flower seedlings in-vitro from the inner net cage is 10cm away from the bottom of the cement pond, the bottom of the inner net cage is 10cm away from the bottom of the outer net cage, selecting young shrimp holding more than 200 young shrimp holding in the inner net cage according to 40-50% of the selection pressure, and fishing out the young shrimp holding in the young shrimp holding amount and timely leaving the young shrimp in the inner net cage according to the young shrimp holding amount of 20-30/ 2 ; (2) Temporary culture of water-bloom seedlings And (3) temporarily culturing the isolated water flower seedlings in a net cage with a mesh of 40-60 meshes for 2-3 days, wherein the temporary culturing density is 10-15 thousands of tails/m 2 , and mainly feeding yolk water filtered by using 60-mesh bolting silk mesh cloth, so as to feed the water flower seedlings.
  5. 5. The method for improving the germplasm of a crayfish on the market in advance according to claim 4, wherein the standard and coarse specific steps of the crayfish fries are as follows: (1) Coarse marking facility The standard thick pond is provided with a required area of 1-2 mu, a length of 70-150 m, a pond width of 8-10 m, a pond depth of 0.8-1.0 m and a slope ratio of 1 (1-2), and a water inlet and drainage system is built by utilizing two layers of impermeable geomembranes and 40 mesh polyethylene mesh fabrics to protect slopes, wherein the bottom of the pond is flat and slightly inclined to a water outlet; a plastic greenhouse, namely erecting a plastic greenhouse steel frame above the standard thick pool, wherein the steel frame greenhouse is 80-160 m long, 9-10 m wide and 2-3 m high, and paving a transparent plastic film on the greenhouse to increase the temperature and water temperature in the greenhouse; Hanging brushes with the length of 70-80 cm in the standard coarse pool, hanging the brushes in water, wherein the bottoms of the brushes are 10-15 cm away from the bottoms of the water bodies, 3 rows of brushes are arranged in the standard coarse pool, a row of brushes with the width of 100-150 cm are respectively arranged along two sides of the standard coarse pool, a row of brushes with the width of 250-300 cm are arranged in the middle of the standard coarse pool, the interval of each row of brushes is 20cm, and the interval of each row of brushes is 150-200 cm; The oxygenation facility is that nano aeration discs with the diameter of 20-40 cm are arranged between each row of hairbrushes in the standard coarse pool, 1 nano aeration disc is arranged every 2-3 m, and each mu of nano aeration discs is provided with Roots blower or vortex aerator according to the power of 0.4-0.5 kw; (2) Pool cleaning, disinfecting and fertilizer water Removing excessive silt 10-15 days before the water flower seedlings are put in culture, disinfecting by using a quicklime pool, and carrying out water quality culture by using a biological fertilizer and chlorella; (3) Flower seedling stocking After water quality fertilizer is applied, carrying out water detoxification and water spray seedling water test by using an organic acidolysis toxin agent, and then carrying out water spray seedling stocking, wherein 150-200 water spray seedlings with the stocking specification of 8-10 ten thousand seedlings/kg are planted in each m 2 ; (4) Feed feeding Feeding 2 times (6:00-7:00, 17:00-18:00) every day, wherein the feeding amount accounts for 60% of the whole day in the afternoon, the feeding process comprises the steps of feeding shrimp milk powder and artemia larvae (10 days), crushing materials (10-15 days) of materials (1 mm in particle size) of materials (1 mm) and materials (30-35 days) of materials (1 mm in particle size), feeding 40 g per day every ten thousand shrimp larvae initially, uniformly feeding in a whole pond, setting a feeding table, adjusting the feeding amount in time according to the feeding condition, and periodically mixing clostridium butyricum, lactobacillus or immune polysaccharide in the feed to enhance liver and intestine health and disease resistance of the shrimp larvae; (5) Water quality regulation The method comprises the steps of using low temperature resistant bacillus 1 time every 3-5 days, using potassium hydrogen persulfate composite salt 1 time every 5-7 days, changing water 1 time every 5-7 days by using well water, changing water 10-20% each time, keeping good water quality and promoting rapid growth of shrimp larvae; (6) Shrimp larvae fishing After careful cultivation for 50-60 days, the specification of the shrimp larvae in the standard rough pond reaches 400-600 tails/kg, a continuous sunny day is selected, all brushes are removed, the shrimp larvae are caught by using a land-saving cage, and excellent individuals are selected and put in a prepared parent shrimp cultivation rice field.
  6. 6. The method for improving the germplasm of a crayfish on the market in advance according to claim 5, wherein the specific steps of the backup parent cultivation are as follows: (1) Paddy field preparation After harvesting rice, thoroughly removing straws, thoroughly rotary tillage and solarization for more than 50 days, adding water to transplant waterweeds in the last 12 months, wherein the planting area of the waterweeds accounts for 30-40% of the area of the rice field, and the temperature rise in 2 months is stabilized at more than 8 ℃, so that the rapid growth of the waterweeds is promoted by using grass fertilizers; (2) Shrimp larvae screening and stocking The standard rough pond shrimp larvae are combined for catching and separately culturing, large-specification shrimp larvae with specification of more than 2g are screened out from the cultured shrimp larvae according to the selection pressure of 40-50%, and are put into a prepared rice field, and 15-20 kg of shrimp larvae are bred per mu; (3) Feed feeding Feeding the shrimp larvae according to weather after feeding, selecting to feed the crayfish pellet feed (with the grain diameter of 1.0-2.0 mm and the protein content of 36%) 1 time in the noon on a sunny day if the air temperature is above 10 ℃, not feeding the crayfish pellet feed if the air temperature is below 10 ℃, feeding the crayfish pellet feed 1 time per day after 3 months, and the daily feeding rate is 1-3%, wherein the water quality and the water grass maintenance are regulated by weight in the cultivation process, the water grass is kept to be good, the water grass is light green and the coverage area is 50%; (4) Backup parent fishing and screening The shrimp larvae are carefully cultured for 50-60 days, the specification of the backup parent is more than 20g, the backup parent is caught by using a non-land cage, a basic selection group is provided for selecting excellent parent, the specification of the parent shrimp is more than 25g, the selection pressure is 40-50%, and the parent shrimp selected is put into a breeding rice field of egg-holding shrimp.
  7. 7. The method for improving the germplasm of the crayfish on the market in advance according to claim 6, wherein the 2 nd breeding generation is selected, so that the four crayfish growth stages of the egg-holding crayfish, the young crayfish, the parent crayfish are repeatedly selected according to the strong fertility and the fast growth as the breeding targets, and the crayfish excellent germplasm population with strong fertility and fast growth can be established after 3-5 breeding generations.

Description

Method for improving germplasm of crayfish on market in advance Technical Field The invention belongs to the technical field of improved breeding of crayfish, and particularly relates to a method for improving the germplasm of crayfish on the market in advance. Background At present, with the rapid expansion of the culture scale of the crayfish, the market supply amount shows seasonal imbalance, wherein the crayfish is concentrated to market in 5 and 6 months and is supplied more than required, the culture cost is high, the benefit is lower, and the like, the crayfish on the market before 5 months has less market supply amount, supply and demand, high market price, few diseases, low culture cost, good benefit and the like. At present, the early shrimps mainly depend on offspring to breed a small amount of overwintering shrimps caught in a rice field, and the yield and the time to market are unstable. Paddy field crayfish undergoes years of closed culture, large and small catching, reverse selection and the like, so that germplasm degeneration is caused, and the crayfish is mainly characterized by reduced fertility, slow growth, poor stress resistance, miniaturized body type and the like. At present, most folk practitioners are introduced and supplemented into the self-bred shrimp fields in different places every year to improve the germplasm, and the improvement method has a certain effect on improving the germplasm, but the mode is extensive, accurate improvement is difficult to achieve, and the excellent properties of the population are easy to lose. In view of the above, the invention respectively screens good individuals in four stages of paddy field autumn egg-holding shrimp reproduction, workshop temperature control incubation, plastic greenhouse water flower seedling standard coarse and paddy field backup parent shrimp cultivation, and respectively selects egg-holding shrimps with large egg holding quantity, young shrimp with large young shrimp holding quantity, large specification shrimp and commodity shrimps according to 40-50% screening proportion in each stage, and breeds good groups with strong fertility, fast growth and early marketing through more than 3 generations of systematic breeding, thereby improving the quality of crayfish seeds. Disclosure of Invention In order to solve the problems existing in the conventional crayfish fine breed breeding, the invention provides a method for improving the crayfish germplasm in advance, overcomes the defect that the breeding process is slow when screening is performed once in the parent crayfish stage in each generation in the conventional crayfish breeding process, can screen good individuals for 4 times in each breeding generation, improves the efficiency of seed selection, accelerates the gathering speed of crayfish good genes, accelerates the germplasm improvement process, combines the growth speed and the fertility with the breeding target, and establishes good groups in the morning. In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: a method for improving the germplasm of crayfish on the market in advance uses paddy field, hatching workshop, net cage and plastic greenhouse facilities to carry out screening and breeding in the main growth stages of four crayfish of egg-holding crayfish, young crayfish and backup parent, and each stage preferably selects a good individual with a certain proportion according to the target characters, thereby accelerating the aggregation of the target good characters, quickly obtaining the colony with strong fertility, quick growth and early marketing, and accelerating the progress of improving the germplasm of crayfish. As a preferable technical scheme of the invention, the specific steps of the breeding stage of the egg-holding shrimp in the method for improving the germplasm of the crayfish on the market in advance are as follows: (1) Rice field engineering The method comprises the steps of (1) excavating L-shaped, U-shaped or annular shrimp grooves around a paddy field, wherein the groove width is 2-3 m, the depth is 50-60 cm, the ridge height is 50-60 cm, the ridge width is 1-2 m, sub-ridges are arranged along one side of the shrimp grooves close to the field, the sub-ridges are 40-50 cm in width and 10-20 cm in height, the gradient ratio of each ridge groove is 1 (1-2), the area of each groove occupies not more than 10%, and an escape preventing net is arranged along the position 10-20 cm below the ridge surface, so that parent shrimps can make holes at the position 10-20 cm below the ridge slope, and water is conveniently added to stimulate the egg-holding shrimps to make holes; (2) Aquatic weed transplanting Transplanting 2 rows of waterweeds in the shrimp grooves in the middle ten days of 3 months, transplanting 2 rows of waterweeds every 8-10 m on the field surface, wherein the planting distance of the waterweeds is 4-5 m, and the coverage area of the waterw