Techniques of culturing catfish in rice fields

Fish culture in rice fields has been further developed in Wuyishan City, Fujian Province in recent years. Raising local catfish or leather beard catfish in paddy fields in mountainous areas has better economic benefits. The techniques of catfish culture are summarized as follows:

Selection and facilities of catfish paddy field conditions of catfish can be used to raise catfish in early, middle and late rice fields with sufficient water source, convenient drainage and irrigation, strong water holding capacity, drought and no flood. But it is better to raise catfish in late rice fields.

Rice field infrastructure ① heightens and strengthens the ridges. The ridge of the field should be increased to 40 cm ~ 50 cm and 30 cm ~ 35 cm wide, which should be solid and firm, not collapsing and not leaking, so as to prevent fish from escaping. ② dug fish slips and fish ditches. Fish slips, also known as fish pits, fish nests, are deeper places in the paddy field. Fish slipping is not only the main place for fish to perch, avoid summer heat and grow, but also an important measure to solve the contradiction between fertilization, pesticide application and drying in paddy fields. Its shape is square, long, round and so on. Can be opened in the middle, the edge of the field or water outlet, try to choose a more hidden place, anti-alarm, anti-theft, convenient for cleaning, observation, bait and fishing. Each fish slips 3 square meters ~ 5 square meters, 50 cm ~ 80 cm deep, a little deeper is better, which is beneficial to the growth of fish. The area of fish slips accounts for 3% or 5% of the area of this field.

The fish ditch is the channel for the fish to live and enter the fish. Generally wide 30 cm ~ 35 cm, depth 30 cm ~ 40 cm, the layout shape has "day", "field" and so on, often depends on the shape of the field. The fish ditch area accounts for about 3% or 5% of the paddy field area. The time for digging fish ditches and slipping fish can be before or after transplanting. It is easy to carry out before transplanting rice seedlings, it is convenient to unearth, and the quality of the ditch is good, but it must be rearranged when transplanting rice seedlings, and it is more troublesome to dig ditches after transplanting rice seedlings. The seedlings should be replanted on both sides of the ditch as far as possible to reduce rows without reducing plants as far as possible.

The installation of the anti-escape fence should be installed at the injection and discharge outlet of the paddy field, which should be located at the diagonal ridge of the field, the water flow is smooth and evenly passes through the whole field. Fish fence materials can be made of bamboo rafts, plastic strips and barbed wire. It is generally 60 cm long and 40 cm wide, with a height of 20 cm ~ 40 cm higher than the ridge of the field, and 10 cm ~ 15 cm of soil embedded in the lower part of the ridge to prevent catfish from jumping over or escaping from the bottom.

Culture management technology

In order to make full use of the aquatic natural bait in the paddy field, the breeding mode of stocking local catfish or leather-bearded catfish with a small amount of grass and carp was adopted.

The size and quantity of catfish are mainly in the mode of raising catfish. the number of species with catfish size of 1.5 cm ~ 3 cm is 300 ~ 500. The culture period is from April to August, and the average individual length of local catfish is 0.25 kg ~ 0.5 kg. Leather beard can grow to 1 kg ~ 1.5 kg. The survival rate is 40% to 50%, the output can reach 60 kg ~ 120 kg, and there is a certain amount of grass and carp harvest, with remarkable results. The output of rice can reach about 500 kg ~ 600 kg.

The stocking time is generally 7 ~ 10 days after transplanting, and the fish can be put into the fish slippery. If the water temperature is suitable, if the water temperature is about 16 ℃ ~ 20 ℃, some commercial feed can be properly used in the rice fields with rich bait, and if the paddy fields are thinner, they can be fed with more feed or appropriate amount of organic fertilizer, so that the fish species can have bait to adapt to the new living environment, so as to facilitate future feeding and management.

Management technology: raising catfish in paddy field, mainly rice, making full use of the ecological conditions of paddy field, correctly dealing with the relationship between paddy field fish culture and fertilization, pest control and sun drying, so as to make rice and fish symbiosis with the purpose of double harvest.

(1) fertilization: excessive fertilization or incorrect method will be harmful to fish. Fertilization is mainly based on base fertilizer and supplemented by topdressing. Organic fertilizer must be fermented before it is applied. The dosage is about 500 kilograms per mu. The application of chemical fertilizer is 5 kg ~ 10 kg urea, 10 kg ~ 15 kg ammonium sulfate, 3 kg ~ 7 kg potassium nitrate and 5 kg superphosphate per mu. When fertilizing, we should try to avoid harming catfish, or half a field can be released in turn.

(2) Pesticide application: fish culture in rice field can swallow some pests, rice diseases and insect pests must select pesticides with high efficiency and low toxicity, and strictly control the concentration. Before application, the fish ditch should be cleared and the water level should be lowered so that the fish can enter the fish and check before applying the medicine. Minimize the damage of pesticides to fish. After application, the dynamics of the fish should be observed and fresh water should be injected at the right time, so that the fish can be kept safely until the fish are harvested.

(3) Field management: high yield of rice, the key to a good harvest of fish is that the fish do not escape, the fish do not die, of which dry water is the most important. Therefore, frequent field inspection and inspection should be done. Check the activities of fish, food and water quality, as well as the growth of rice, decide to apply bait and fertilization, apply pesticides, check whether the ridges of the fields are collapsing or leaking, whether the fences are strong, whether harmful animals sneak in, prevent drought before rainstorms, and prevent flooding and escape. The bait of cultured adult fish must be observed in terms of water quality, fish condition, timing, appropriate amount, positioning and quality assurance.

After 5 ~ 6 months of field feeding, the fish has reached the harvest season. Fish are usually caught 10-15 days before rice harvest. Before harvesting, it is necessary to dredge the ditch and prepare fishing tools, such as copying net, small pulling net, cage, bucket and so on. When the fish is collected, the water should be released slowly, so that the fish can be concentrated from the ditch to the fish and caught. To meet the specifications on the market, the small specifications will be left to turn to small ponds and then continue to raise in the coming year, and after the fish harvest, the rice fields will dry and the rice can be harvested.