Detailed Explanation of Key Techniques for Loach Farming in Rice Fields
Advantages of Farming Loach in Rice Fields
1. Without destroying the original ecosystem of the rice field or increasing the use of water resources, it can achieve the effect of using one water source for two purposes and harvesting two crops from one land, directly improving economic benefits.
2. The ecological effect is more prominent, mainly manifested in that loach can directly eat some harmful insects in the water, playing part of the role of biological pest control, saving pesticides and reducing food contamination.
Loach prefers to inhabit the surface layer of silt with decayed and cracked soil at the bottom. In addition to breathing with gills, it can breathe through its skin and intestines. Loach is an omnivorous fish that prefers to forage at night, feeding on insects, small crustaceans, tender leaves of aquatic plants, as well as diatoms, blue-green algae, green algae, yellow-green algae and zooplankton.
Under artificial rearing conditions, plankton feed is cultivated through fertilization, and residual feed and fecal debris deposited at the bottom of the pond can also serve as its food. Artificial rearing can also involve feeding commercial feed, such as peanut cake, rice bran, wheat bran, soybean cake, silkworm pupa powder, snails, earthworms, tubifex, fish meat, and the internal organs of poultry and livestock. Loach is small in size, light in weight, and greedy; when overfed, it is prone to indigestion, which affects normal breathing and causes death from bloating.
Loach is a warm-water fish and appears earthy yellow in rice fields. Its growth water temperature is 15-34 degrees, and the most suitable growth water temperature is 24-30 degrees. When the water temperature drops below 5-6 degrees or rises above 35-36 degrees, it burrows into the mud layer 10-30 cm deep to hibernate.
Rice Field Construction
For farming loach in rice fields, choose rice fields with sufficient water sources, good water quality, and an area of 2-10 mu, and build an 80 cm high anti-escape wall around the rice field using cement or plastic boards, film, window screens, etc. (embedded 30 cm into the mud). Along the field ridge, build a 20 cm wide step, 15 cm from the top of the field ridge. Dig a “”-shaped water ditch around the field and in the center, with a ditch width and depth of 50 cm. There should be 1 inlet pipe, 1 drainage pipe and 1 overflow pipe, with all pipe openings blocked by fine iron wire mesh, and the drainage pipe is usually sealed with cement.
Loach Seed Stocking
The loach is best sourced from a loach original seed farm or caught from natural waters. It is required to be robust and disease-free without injuries, at the age of 2 years, with female body weight 15-25 g and male body weight above 12 g. In late February, before the rice field is filled with water, evenly spread 75-100 kg of quicklime per mu for cleaning and disinfection. Apply 1000 kg of fermented pig manure per mu, let the incoming water enter the field after filtration, with a water depth of 30-40 cm in the ditch, to fertilize the water body, and the water transparency should be about 25 cm. After the seedlings turn green, stock 20,000-25,000 loach fry of 3-5 g each per mu. Before stocking, soak them in a 3% salt solution for 10 minutes, and put them into the field after disinfection.
Feeding and Management
1. Fertilization
During the breeding process, in order to ensure a continuous supply of plankton, organic fertilizer must be applied in a timely, small, and even manner. Fertilize once every 10-15 days, using 150 kg per mu each time. In addition, according to the specific water color conditions, apply about 1.5 kg of urea or 2.5 kg of ammonium bicarbonate per mu each time to keep the water body yellow-green.
2. Feeding
Because the density of loach in the field is relatively high, artificial feed should be provided, such as soybean cake, silkworm pupa powder, fly maggots, earthworms, snails, mussels, slaughterhouse offal, rice bran, soybean dregs, rapeseed cake, wheat bran, etc., to supplement the insufficiency of natural food. July-August is the peak growth season for loach. A ratio of 15% silkworm pupa powder, 10% meat and bone meal, and 25% soybean cake is required, with feeding twice a day and a feeding rate of 10%. In September-October, plant-based feed such as wheat bran and rice bran is mainly used, generally fed once in the morning and once in the afternoon each day, with the feeding amount being 2%-4% of the total weight of the loach. In early spring and late autumn, about 2%. The specifics should be flexibly controlled according to the feeding situation of the loach. Generally, it is appropriate if the feed is basically eaten up within 1-2 hours after each feeding.
3. Water Level Control
Water level control is extremely important. The actual water level above the field surface is generally controlled at more than 5 cm. Add new water in a timely manner, generally once every half month, and properly deepen the water level during the high-temperature season in summer.
4. Disease Prevention and Control
Since loach is suitable for paddy field farming, generally no diseases occur during the breeding process. To prevent red-skin disease, use 10-20 g of furacilin medicated bait each month, mixed with 50 kg of feed and fed for 2-3 days, and spread 10-15 kg of quicklime per mu each month after slaking it into slurry over the whole pond. Rice pesticide application is generally done 3-5 days before transplanting, or 5-7 days after transplanting, applying pesticide once to the seedlings for prevention.
5. Daily Management
Patrol the field twice a day, check the anti-escape facilities, and carefully inspect for leaks especially on rainy days. Prevent invasion by natural enemies (such as water snakes, ducks, etc.), and observe the activity and feeding conditions of the loach. Strictly prohibit water containing highly toxic pesticides such as methamidophos, toxaphene, carbofuran, and sodium pentachlorophenate from flowing in.
Capture Methods
The first is capture by flushing water. Lay nets near the water outlet, release water from the inlet, and because loach has the habit of swimming against the current, lift the nets to catch them after a certain time. This method is suitable when the water temperature is around 20 degrees and the loach is active. The second is bait trapping. Place roasted fragrant bran or wheat bran in bamboo cages, and place the cages in the ditch to lure the loach into the cages. The third is dry-field capture. Slowly drain the field water so that the loach gathers in the exposed ditch soil for capture.