CN111513003A

CN111513003A - Net cage culture method for grass carp reservoir

Info

Publication number: CN111513003A
Application number: CN202010550494.6A
Authority: CN
Inventors: 王武刚; 冯硕恒; 张璐; 米海峰; 尹恒; 吴业阳; 刘梅
Original assignee: Tianjin Tongwei Forage Co ltd; Tongwei Co Ltd
Current assignee: Tianjin Tongwei Forage Co ltd; Tongwei Agricultural Development Co Ltd
Priority date: 2020-06-16
Filing date: 2020-06-16
Publication date: 2020-08-11
Anticipated expiration: 2040-06-16
Also published as: CN111513003B

Abstract

The invention discloses a method for culturing grass carps in a water reservoir net cage, and relates to a reservoir culture technology of grass carps. The scheme is provided aiming at the problems of low survival rate and low yield of Chinese herbal fish culture in the prior art. The method comprises the steps of selecting a water area, planning specifications of a net cage and a fish raft, installing the net cage, matching and stocking fish species and managing feeding; and the step of feeding management is to utilize the mounted net cages to perform classified collection and separated-box cultivation on roes and grass carps and/or utilize the net cages to perform classified collection and separated-box cultivation according to the sizes of the grass carps. The advantage lies in, utilizes the unique design of box with a net, can separate grass carp and roe, filters out and separates different box with a net cultivates. Through batch filtering, fish shoal is classified according to size, so that large individual difference is avoided, the yield and efficiency of grass carp culture are improved, and the culture cost is reduced.

Description

Net cage culture method for grass carp reservoir

Technical Field

The invention relates to a reservoir culture technology of grass carps, in particular to a net cage culture method of a grass carp reservoir.

Background

Grass carp belongs to family Cyprinales, subfamily Analuodiaceae, genus grass carp. Common names of grass carps are: grass carp, grass root (northeast), grass carp (southwest), grass carp (south), mollissima, black herring and the like. The river and lake inhabiting the plain area generally prefer to be in the middle and lower layer of water and the multi-water grass area near the bank. It is lively, swims rapidly, and often finds food in groups. Typical herbivorous fish. The young grass carp eats larvae, algae and the like, and the grass carp eats some meat foods, such as earthworm, dragonfly and the like. Overwintering in deep water of a main stream or a lake. In the reproductive season, the parent fish has a upstream habit. The grass carp is one of four Chinese freshwater cultured Chinese fishes due to rapid growth and wide feed source, is popular among people in the aquaculture market of China, is firstly simple in preparation method and very many in cooking means, is secondly a native fish in China, is low in culture cost due to strong environmental adaptability and simple in culture, and is selected as a culture object by a plurality of farmers. Moreover, the growth speed of the grass carps is very high, which means that the culture efficiency of the grass carps is very high, and under the continuous efforts of agricultural science and technology workers and farmers, some culture methods such as lakes and net cage culture are explored. However, the survival rate and the yield of the culture methods are not high, and the culture enthusiasm of culturists is influenced.

Disclosure of Invention

The invention aims to provide a method for culturing grass carp in a water reservoir net cage, which aims to solve the problems in the prior art.

The invention relates to a method for culturing grass carp in a water reservoir net cage, which comprises the following steps: the method comprises the following steps of selecting a water area, planning specifications of a net cage and a fish raft, installing the net cage, matching and stocking fish species, and managing feeding; and the step of feeding management is to utilize the mounted net cages to perform classified collection and separated-box cultivation on roes and grass carps and/or utilize the net cages to perform classified collection and separated-box cultivation according to the sizes of the grass carps.

The net cage is fixedly provided with positioning rods at four inner corners, at least two screen meshes are arranged at the bottom end of the net cage, four ends of each screen mesh are fixed on corresponding supporting rods, sliding blocks are arranged at two ends of each supporting rod, sliding grooves matched with the sliding blocks are formed in two sides of each positioning rod, the sliding blocks are arranged in the sliding grooves, fixing rings are arranged at the ends of the supporting rods, one end of each fixing ring is connected with one end of a net-drawing steel wire, and the other end of each net-.

Supporting steel pipes are fixed at four corners of the outer side of the net cage, and the supporting steel pipes are provided with traction mechanisms which correspond to the screen meshes one by one; the traction mechanism comprises a case arranged at the top end of a support steel pipe, a motor is arranged in the case, an output shaft of the motor is connected with a winding rod, a fixed mounting ring is arranged on the support steel pipe, a lead ring is fixed at the front end of the fixed mounting ring, an extension end of a net-pulling steel wire is fixed on the winding rod, and one end of the net-pulling steel wire penetrates through the lead ring and is arranged on the fixed ring.

The water area selection method specifically comprises the following steps: the geographical position is selected in a bay, in which water is selected to have a water depth of more than 36.32 meters and a water flow of less than 0.1 meter per second.

The steps of planning the specifications of the net cage and the fish raft are as follows: the net cage is made of polyethylene nodular netting, the specification of the net cage is an open net cage, the length of the open net cage is 5 meters, the width of the open net cage is 5 meters, the depth of the open net cage is 5 meters, and the mesh is 1.5 cm; the fish raft is a bridge cut type raft with a frame of 5 meters by gasoline barrels and steel pipes, and 10-16 net cages are arranged in each raft.

The step of installing the net cage specifically comprises the following steps: after the net cage headrope is straightened and tightened, the corner ropes at the four corners are tied on a fish raft steel pipe frame, the periphery of the net cage headrope is fixed on the frame side by winding and tying through a polyethylene steel rope, and stones or sand bags with the weight of 3-5 kg are hung outside the four bottom corners of the net cage to be used as sinkers, so that the net cage is fully developed and formed in a water body, and the net wall is 0.5 m higher than the water surface; after the net cage is installed, the fish seeds are launched 7-10 days before entering the cage.

The fish breeding method comprises the following steps: the fingerling is formed by combining grass carp fingerlings with flower chub fingerlings; the grass carp fingerling stocking specification is 150 g/tail, the grass carp fingerling is soaked and washed for 1020 minutes by using a saline solution with the concentration of 3% -5%, and the stocking density is controlled at 175 tail/square meter; the stocking density of spotted silver carp fingerlings is controlled to be 10 fish/square meter.

Before the fish seeds are put into the net cage for culture, the fish seeds are firstly cultured in a concentrated way and then put into the net cage for culture after the vaccine is injected.

The step of feeding management further comprises: the feed is prepared by matching compound feed and green feed; the compound feed is a special puffed feed for grass carp with 28-30% of protein content; the green feed is land grass, and is sprayed and washed with 0.1 percent bleaching powder solution for disinfection when being fed; the grain size of the selected pellet feed in the early stage of cultivation is 2.0 mm, and the grain size of the selected pellet feed in the middle and later stages of cultivation is 3.0 mm; the mixed feed is firstly added, and then the green feed is added, wherein the feeding weight ratio of the mixed feed to the green feed is 3: 1.

When feeding, the method of splashing water or knocking the frame and the like can be adopted to make food calling sound.

The method for culturing the grass carp in the water reservoir by using the net cages has the advantages that the unique design of the net cages is utilized, the grass carp and roe can be separated, different net cages are filtered and separated for culturing, the yield of cultured grass carps is increased, and the culturing cost is reduced. Through batch filtering, fish shoal is classified according to size, so that large individual difference is avoided, and the breeding efficiency is further improved. The cage is used for centralized cultivation, so that the fish seeds injured or died due to illness during transportation can be removed conveniently. The concentrated vaccine injection is carried out on the fish seeds, the problem that a large number of fish fries die due to illness in the culture process is prevented, and the culture survival rate is improved. The reasonable feeding method ensures that the cultured grass carps can take sufficient feed.

Drawings

FIG. 1 is a flow chart of a grass carp reservoir cage culture method of the present invention;

FIG. 2 is a schematic view of the connection structure of the net cage and the supporting steel pipes according to the present invention;

FIG. 3 is a schematic diagram of the cage construction of the present invention;

FIG. 4 is a cross-sectional view of a cage construction of the present invention;

FIG. 5 is an enlarged view of the invention at A;

fig. 6 is an enlarged view of the present invention at B.

In the figure: 1. positioning a rod; 11. a chute; 2. screening a screen; 21. a strut; 211. a slider; 212. a fixing ring; 3. supporting the steel pipe; 31. a chassis; 311. a motor; 312. a wire winding rod; 313. drawing a net steel wire; 32. fixing the mounting ring; 321. a wire loop.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1, a method for cage culture of grass carp in a water reservoir includes the following steps:

s1: selecting a water area: the geographical position is to select a bay which is close to the village, convenient to traffic, faces the sun and is leeward, is far away from a channel and a wharf, has no pollution source in the upstream and surrounding areas and has thin water quality. The water depth is more than 36.32 m, and the water flow is preferably in the water area within 0.1 m/s.

S2: the specification of the net cage and the structure of the fish raft are as follows: the net cage is made of polyethylene nodular netting, and is 5 m long, 5 m wide, 5 m deep and 1.5 cm in mesh size. The fish raft is constructed into a 5 m by 5 m frame bridge valve type row by gasoline drums and steel pipes, and generally 10-16 boxes are installed in each row.

Construction of the cage referring to fig. 2-6, at least three embodiments of the cage are provided:

embodiment one of the Net cage

And positioning rods 1 are fixed at four corners in the net cage. The bottom in the net cage is provided with a screen 2. The screen 2 is fixed on the support rods 21 at four ends. The two ends of the supporting rod 21 are provided with sliding blocks 211. And sliding grooves 11 matched with the sliding blocks 211 are formed in the two sides of the positioning rod 1. The slider 211 is disposed in the chute 11. The end of the strut 21 is provided with a fixing ring 212. And the four corners outside the net cage are fixedly provided with support steel pipes 3. And the top ends of the two diagonally opposite support steel pipes 3 are fixed with traction mechanisms. The pulling mechanism comprises a case 31, and a motor 311 is arranged in the case 31. An output shaft of the motor 311 is connected to the winding rod 312. The support steel pipe 3 is provided with a fixed mounting ring 32. The lead ring 321 is fixed at the front end of the fixed installation ring 32. One end of a steel wire 313 is fixed on the winding rod 312, and the other end of the steel wire 313 is installed on the fixing ring 212 through the wire ring 321.

The screen 2 is provided with two upper and lower layers, the mesh size of the upper layer is 45 mm, and the mesh size of the lower layer is 5 mm. The area of the screen 2 is larger than that of the bottom of the net cage, and the screen 2 is in a contraction state at the bottom of the net cage. Grass carp enters into mature period at 3-4 years old, and generally spawns in 4-7 months. When the grass carp spawns, the spawn falls to the lower-layer screen. The motor 311 drives the winding rod 312 to rotate, and the net pulling steel wire 313 drives the upper layer of the sieve net to move upwards to filter out the grass carps for changing a net cage culture. Collecting roe, hatching and culturing the collected roe in boxes, increasing the yield of cultured grass carp, and reducing the culture cost

Embodiment two of the net cage

The difference between this embodiment and the first embodiment of the net cage is that the mesh sizes of the upper and lower layers of the screen mesh are different. The mesh size of the upper layer was 65 mm, and the mesh size of the lower layer was 45 mm. After the individual difference appears in the shoal of fish, motor 311 drives wire winding rod 312 and rotates, draws net copper wire 313 to drive upper screen cloth and filters out ripe grass carp and sell, and remaining less grass carp is bred again, through filtering in batches, can carry out size classification to the shoal of fish.

Embodiment three of the net cage

The difference between this embodiment and the first embodiment of the net cage lies in the number of layers of the screen mesh, the mesh size and the number of the drawing mechanisms. The number of the layers of the screen cloth is set to be three layers, namely an upper layer screen cloth, a middle layer screen cloth and a lower layer screen cloth, wherein the mesh size of the upper layer screen cloth is 65 mm, the mesh size of the middle layer screen cloth is 45 mm, and the mesh size of the lower layer screen cloth is 5 mm. And the top ends of any three supporting steel pipes of the net cage are respectively fixed with a traction mechanism so as to be respectively connected with the fixing rings of the three layers of the net screens corresponding to the supporting rods through the net-pulling steel wires which are respectively connected. The fish and egg classification and the fish school size classification of the first embodiment and the second embodiment can be realized simultaneously. The specific method comprises the following steps: when fish and roe are required to be classified, the upper layer screen and the middle layer screen are pulled simultaneously to separate grass carp, and then the lower layer screen is pulled to separate roe. When fish shoal size classification is needed, only the upper layer of the sieve net is pulled to separate out mature grass carps, and the smaller grass carps are kept in the net cage for continuous culture.

S3: installing a net cage: after the net cage headrope is straightened and tightened, the angle ropes at the four corners are tied on the fish raft steel pipe frame, and the periphery of the net cage headrope is fixed on the frame edge by winding and tying with a polyethylene steel rope. And 3-5 kg-weight stones or sandbags are hung outside the four bottom corners of the net cage to be used as sinkers, so that the net cage is fully formed in the water body. The net wall is 0.5 m higher than the water surface, and the net cage is arranged to be launched 7-10 days before the fish seeds are put into the box, so that the net is smooth after the algae are attached to the net, and the skins and the scales of the fish seeds are prevented from being abraded and injured.

S4: fish species matching and stocking: the fingerling selection is mainly performed on grass carp fingerlings, and a proper amount of spotted silver carp fingerlings are intercropped. The standard of stocking grass carp fingerlings is 100-. After the fish seeds are selected, the fish seeds are soaked and washed for 10 to 20 minutes by a salt solution with the concentration of 3 to 5 percent. Then, the grass carp fingerlings are bred in boxes according to the breeding density of 175 fish seeds/square meter and the breeding density of 10 silver carps/square meter. Before the fingerlings are separately put into the net cage for cultivation, the fingerlings are firstly cultured in a concentrated mode, so that the fingerlings which are injured or died due to illness during transportation can be conveniently removed. After the vaccine is injected, the fish fries are thrown into the net cage for culture, so that the problem that a large number of fish fries are ill and die in the culture process is solved, and the culture survival rate is improved.

S5: cultivation management: the feed is mainly mixed feed and supplemented by green feed. The concentrated feed is special puffed feed for grass carp with 28-30% of protein content, and the green feed is rich land grass in rural areas. The grain size of the pellet feed in the early stage of cultivation is 2.0 mm. The grain size of the pellet feed in the middle and later stages of cultivation is 3.0 mm. The mixed feed is firstly added, and then the green feed is added, wherein the feeding weight ratio of the mixed feed to the green feed is 3: 1. The early stage is before one year, the middle stage is one to three years, and the later stage is after three years. When feeding, the fish can be splashed with water or knocked on the frame to generate food calling sound, so that the fish forms conditioned reflex, and the fish can float upwards in time and grab food integrally. The grass carp feed can be fed sufficiently, the occurrence of large individual difference is avoided, and the breeding efficiency is improved. Fresh green feed is selected and is sprayed and washed with 0.1 percent of bleaching powder for disinfection when being fed. In the initial period of each feeding, the fish school does not float upwards completely to snatch, the feeding speed is slower, and the feeding amount is less. In the middle period, the fish school completely floats upwards to snatch food and snatch the food fiercely, the feeding speed is higher, and the feeding amount is larger. In the later period, most fish schools are full and sink, only a few individuals are weak and not full, the feeding speed can be reduced, and the feeding amount can be reduced.

In conclusion, the grass carp reservoir cage culture method provided by the invention is low in fatality rate, high in screening efficiency, uniform in batch, high in survival rate and capable of increasing the yield in proportion to the survival rate.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be able to cover the technical solutions and the inventive concepts of the present invention within the technical scope of the present invention.

Claims

1. A method for culturing grass carp in a water reservoir net cage comprises the following steps: the method comprises the following steps of selecting a water area, planning specifications of a net cage and a fish raft, installing the net cage, matching and stocking fish species, and managing feeding;

the method is characterized in that the raising management step comprises the steps of utilizing the mounted net cages to carry out classified collection and separated-box culture on roes and grass carps and/or utilizing the net cages to carry out classified collection and separated-box culture according to the sizes of the grass carps.

2. The grass carp reservoir cage culture method according to claim 1, wherein the cage is fixedly provided with positioning rods (1) at four corners inside, at least two screens (2) are arranged at the bottom end inside, four ends of each screen (2) are fixed on corresponding supporting rods (21), sliding blocks (211) are arranged at two ends of each supporting rod (21), sliding grooves (11) matched with the sliding blocks (211) are formed in two sides of each positioning rod (1), the sliding blocks (211) are arranged in the sliding grooves (11), fixing rings (212) are arranged at the ends of the supporting rods (21), the fixing rings (212) are connected with one ends of netting steel wires (313), and the other ends of the netting steel wires (313) extend upwards freely.

3. The grass carp reservoir cage culture method according to claim 2, wherein supporting steel pipes (3) are fixed at four corners of the outer side of the cage, and the supporting steel pipes (3) are provided with traction mechanisms which correspond to the screens (2) one by one; the drawing mechanism comprises a case (31) arranged on the top end of a support steel pipe (3), a motor (311) is arranged in the case (31), an output shaft of the motor (311) is connected with a winding rod (312), a fixed mounting ring (32) is arranged on the support steel pipe (3), a lead ring (321) is fixed at the front end of the fixed mounting ring (32), an extending end of a net-drawing steel wire (313) is fixed on the winding rod (312), and one end of the net-drawing steel wire (313) penetrates through the lead ring (321) to be installed on a fixing ring (212).

4. The grass carp reservoir cage culture method according to claim 1, wherein the water area selection specifically comprises the following steps: the geographical position is selected in a bay, in which water is selected to have a water depth of more than 36.32 meters and a water flow of less than 0.1 meter per second.

5. The grass carp reservoir cage culture method according to claim 1, wherein the step of planning the specifications of the cages and the fish rows is specifically as follows: the net cage is made of polyethylene nodular netting, the specification of the net cage is an open net cage, the length of the open net cage is 5 meters, the width of the open net cage is 5 meters, the depth of the open net cage is 5 meters, and the mesh is 1.5 cm; the fish raft is a bridge cut type raft with a frame of 5 meters by gasoline barrels and steel pipes, and 10-16 net cages are arranged in each raft.

6. The grass carp reservoir cage culture method according to claim 5, wherein the cage installation steps are as follows: after the net cage headrope is straightened and tightened, the corner ropes at the four corners are tied on a fish raft steel pipe frame, the periphery of the net cage headrope is fixed on the frame side by winding and tying through a polyethylene steel rope, and stones or sand bags with the weight of 3-5 kg are hung outside the four bottom corners of the net cage to be used as sinkers, so that the net cage is fully developed and formed in a water body, and the net wall is 0.5 m higher than the water surface; after the net cage is installed, the fish seeds are launched 7-10 days before entering the cage.

7. The grass carp reservoir cage culture method according to claim 1, wherein the steps of fish breeding and stocking specifically comprise: the fingerling is formed by combining grass carp fingerlings with flower chub fingerlings; the grass carp fingerling stocking specification is 150 g/tail, the grass carp fingerling is soaked and washed for 1020 minutes by using a saline solution with the concentration of 3% -5%, and the stocking density is controlled at 175 tail/square meter; the stocking density of spotted silver carp fingerlings is controlled to be 10 fish/square meter.

8. The method for culturing grass carp in a net cage in a reservoir according to claim 7, wherein the fingerlings are cultured intensively before being put into the net cage, and are put into the net cage for culturing after the vaccine is injected.

9. The method for grass carp cage culture in a reservoir according to claim 1, wherein the step of rearing management further comprises: the feed is prepared by matching compound feed and green feed; the compound feed is a special puffed feed for grass carp with 28-30% of protein content; the green feed is land grass, and is sprayed and washed with 0.1 percent bleaching powder solution for disinfection when being fed; the grain size of the selected pellet feed in the early stage of cultivation is 2.0 mm, and the grain size of the selected pellet feed in the middle and later stages of cultivation is 3.0 mm; the mixed feed is firstly added, and then the green feed is added, wherein the feeding weight ratio of the mixed feed to the green feed is 3: 1.

10. The method of claim 9, wherein the feeding is performed by sprinkling water or knocking the frame to make a food calling sound.