Ecologically efficient culture model of large-scaled sub-loach pond
Large scale loach, also known as Taiwan loach, the introduction of mainland aquaculture has many years of history, technology has matured, in May-October 2017, Guangming County Shanquan Aquaculture Co., Ltd. in Luanfeng Township Gaoyuan Village loach breeding base to carry out ecological and efficient breeding model demonstration, achieved good benefits.
1. Materials and methods
1. Pond preparation
The loach breeding base was selected in Xuyuan Group, Gaoyuan Village, Luanfeng Township. The water source is sufficient and reliable, the water quality is fresh and pollution-free, the physical and chemical indicators are in line with the water quality standards for fishery water, the pond is convenient for entering and draining (self-irrigation and self-discharge), the humus-rich clay soil, the sun is sufficient, the transportation is convenient, and the power is guaranteed.
(1) Pond design
The pond was converted from a rice field with an inlet canal on one side and a drainage canal and flood control ditch on the other side. The total area of the breeding pond is 37 mu, counting 6 mouths, the area varies from 4-8 mu, the depth of the pond is about 200 cm, the water level can reach 150 cm, and the width of the pond is about 100 cm, which is convenient for breeders to push the bucket truck operation, and the lower width is about 500 cm. The bottom inlet of the pond is sloped by 2-3‰ towards the drainage surface, the bottom mud is about 10 cm thick, the inlet and drainage inlet are arranged diagonally, the pond inlet is 20 cm above the highest water surface, and 80 mesh filters are installed to prevent the entry of trash fish, predators and fish eggs. Anti-escape facilities are installed at the drain to prevent fish from running away when draining. The drainage outlet is located at the level of the normal water level of the pond, the drainage bottom is set at the bottom of the pond fish slip, and the inlet and drainage are wrapped in a dense net to prevent loach from escaping. For the convenience of fishing, the pond is equipped with a fish slip connected to the drainage bottom, which is about 3-5% of the total area of the bottom of the pond and is 30-35 cm deeper than the bottom of the pond, and the fish slip is surrounded by masonry and cement.
Around the pond, a purse seine net cloth of about 20 mesh and a purse seine height of 60-80 cm is inserted to prevent the invasion of natural enemies on the ground such as snakes, rats and frogs; the sky net (anti-bird net) is set up around and above the breeding pond, and the width of the mesh is 6 cm to prevent the infringement of loach by birds such as egrets and night herons.
(2) Pond consolidation
2 weeks before the seed stocking, clear the loach pond, plug the loopholes, dredge the drainage pipe, plough the silt at the bottom of the pond, and then clear the pond with quicklime, that is, apply 100 g/m2 of quicklime at a water depth of 10 cm, and immediately after mixing the quicklime with hydration slurry, the whole pond is evenly sprinkled.
(3) Water cultivation bait
After 1 week of clearing the pond, the pond is watered to 40 cm, and a base fertilizer is applied, which uses 300 g/m2 of fermented and decomposed chicken manure to cultivate plankton in the pond water, so that the loach seedlings can feed on the palatable base bait organisms after the next pond.
(4) Aeration equipment installation
4-6 acres of pond with 1.5 KW (380 V) impeller aerator, 6-8 acres of pond with 2.2 KW (380 V) impeller aerator. At the same time, a number of matching microporous aerators are installed, and the power per acre of water surface is configured to be 0.15-0.2 KW. Microporous aerator installation process: Roots blower connected to the air storage buffer device, connected to the main pipe (PVC), connected to the branch pipe, connected to the aeration plate (¤80 cm), set 4-5 aeration discs per acre.
2. Breeding management
(1) Seed stocking
Choose to buy a company in a neighboring county with neat and healthy physique, no disease loach seedlings splash, the seedling release time is May 3, 6, 10 days, calculate the ride, in the early morning the seedlings are transported to the pond, after slow seedling treatment, the loach seedlings into the 3% salt water container Chinese medicine bath for 5-10 minutes after slowly entering the pool. Because dragonflies are found to be circling in the farm during the release of seedlings, dragonflies are used 2-3 days before the loach seedlings go down to the pond to kill dragonfly larvae, water centipedes and other predators; half a month after the release of seedlings, 15-30 tails / mu, and 10-20 tails / mu of summer flowers of the silver carp are used to regulate water quality and prevent the outbreak of cyanobacteria.
(2) Feed feeding
After the splash of the pond, you can feed on high-quality bait organisms such as rotifers, start feeding compound feed after 3-4 days, and buy special feed for loach from brand manufacturers according to each growth stage. The water spray is fed the open powder at the inch seedling stage, the crushed material is fed to the 7 cm stage, the expanded loach is fed at the 7-10 cm stage, the loach above 10 cm is fed the puffed loach feed, and the loach feed is fed into loach above 15 cm. The crude protein of the feed is 45% in the early stage, and then gradually reduces to 38-36% according to the growth of loach seedlings. Feed feeding according to the principle of "four certainties" and "four looks", it is advisable to be full of seven points. The sun has just come out in the morning, the sun sets in the afternoon and the loach feeding peak at 20:00-21:00, and the feeding amount can be tilted appropriately according to this law. It is fed 6 times a day during the water splash cultivation period, 4 times a day from the seedling to 10 cm stage, and 2-3 times a day above 10 cm. The daily bait volume in the splash stage is 8%-10% of the body weight, the daily bait volume in the seedling to 10 cm stage is 3%-5% of the body weight, and the daily bait volume above 10 cm is 1%-2% of the body weight. During the splash cultivation stage, it is advisable to sprinkle chlorella, PSB (photosynthetic bacteria) and other culture opening bait, and feed is fed along the perimeter of the pond, and the feeding point is set at a distance of about 1.5 m from the pond edge.
(3) Water quality management
Water body is the loach to live in the environment, the quality of water is related to the loach survival rate, growth rate and feed rate, the water depth at the seedling stage is maintained at 40-50 cm, appropriate fertilization of water quality, increase the bait organisms; in the middle and late stages, try to increase the water level to 120-150 cm, so that the water quality is fresh, to ensure that the water body is fat, alive, tender and refreshing. One is to try to maintain an appropriate amount of micro-flowing water; the second is to open the aerator frequently, the impeller aerator and the microporous aeration aerator can be started at the same time before sunrise and in the afternoon for 2-3 h, and the microporous aeration aerator can be started in a timely manner according to the specific situation to ensure sufficient dissolved oxygen of the water body; the third is to regularly sprinkle quicklime to adjust the water quality, and regularly sprinkle microbial preparations to change the bottom of the living water.
(4) Disease prevention and control
Follow the principle of "prevention first, prevention and control combined", and adhere to the combination of ecological regulation and scientific drug use. In the spring, pay attention to the prevention of the invasion of parasites such as wheelworms, such as the timely sprinkling of 0.7 mg/L copper sulfate and ferrous sulfate mixture (5: 2) in the whole pool; in the summer, pay attention to the prevention of bacterial diseases (such as the whole pool is sprinkled with chlorine dioxide, povidone iodine, etc.) and do a good job of heat prevention and cooling work (such as building pergolas, transplanting water peanuts, wheel leaf black algae, etc.); in autumn, with the growth of the yield of farmed organisms, attention should be paid to substrate regulation (such as ozone-modified negatives, Bacillus licheniformis, etc.) and prevention of loach hepatobiliary diseases (feed add liver protection and bile protection agents) In winter, grasp the market situation and catch and list in time to alleviate the pressure of pond storage and prevent the occurrence of water mold disease.
2. Results
1. Output
Table 1 For the harvest and sales of seedling stocking and loach, the total area of the experimental demonstration pond is 37 mu, the water and splash seedlings are 12 million, the average stocking density of 324,000 mu, and the total catch is 41,070 kg.
Table 1 Harvest sales of seed stocking and loach
Table 2 Benefit analysis
2. Benefit analysis
From the benefit analysis of Table 2, it can be seen that the total investment in loach farming is 646,700 yuan, the total income is 1,067,800 yuan, the total benefit is 421,100 yuan, the mu benefit is 11,400 yuan, and the input-output ratio is 1: 1.65.
3. Discussion
Different from the construction of loach small area ponds in the past, the demonstration loach culture model pays more attention to the construction of deep water ponds, loach pond area is large, which is conducive to light, water quality regulation and feeding management; large water surfaces and deep water bodies can better give loach living space, increase fish pond dissolved oxygen carrier, facilitate improving yield, and reduce the risk of disease.
The purchase of loach water flower open seedlings for breeding can reduce the cost of loach seedlings; if possible, the loach seedlings can be bred by themselves in the original pond water, which can reduce the cost of loach seedlings and the survival rate is more secure; however,
The management requirements for the preparation of pond seedlings and the management of seedlings during seedling cultivation are higher, and if there is no solid water spray seedling technology, it is recommended to purchase inch seedling culture.
The average size of this batch of farmed loach is small, mainly for local consumption habits, when the loach reaches 100-120 /kg specifications, it is fished in batches using ground cages, which can not only recover funds in time, but also reduce the load of loach in ponds, which is conducive to the rapid growth of loach in ponds.