What are the key techniques for the success or failure of leech farming

SummaryRice field: sufficient water resources, good drainage and irrigation. Facilities: construction of ditches, embankments, anti-escape walls and water inlet and outlet. Density: preferably 800-1000 tails/sq m; about 10 days before stocking, apply 300kg/mu of decomposed organic fertilizer. Bait: feed once each morning and evening at fixed times, feed at the edge of shallow water, ensure the bait is fresh, and remove residual bait in time. Management: patrol the pond frequently to prevent leeches from escaping. Processing: after killing the leeches with 5-10% salt water, rinse them with clean water and dry them in the sun.

Apart from sales channels, technology is one of the key factors determining the success or failure of leech farming profitability. Mastering good techniques can not only reduce input costs and make risks smaller, but also increase output and gain greater profits.

1. Rice field conditions

The farming site is usually chosen in a rice field with sufficient water resources, good drainage and convenient irrigation, and the area should preferably be 1-2 mu.

2. Main facilities

1. Ditches: dig ditches 1.2m deep and 2m wide around the rice field, and dig channels 0.4-0.5m deep and 0.6-0.8m wide in the field. The ditch and channel area is about 25% of the total field area, and the ditches and channels are interconnected, forming a “well” or “abundant” shape.

2. Embankments: the embankment surface is 1m wide and 0.6m high.

3. Anti-escape walls and water inlet and outlet: around the four corners of the rice field, use plastic film to enclose a 0.3m high wall, and install nylon mesh at the water inlet and outlet to prevent leeches from escaping.

3. Rice transplanting

For farming leeches in rice fields, the rice variety chosen is very important. Rice with a long growth period, strong stems, strong tillering ability and resistance to pests and diseases should be selected for planting.

4. Stocking of leech seeds

Leech seeds can be sourced first by buying them from a nearby farm, and second by trapping them in spring and summer with grass soaked in pig blood. The farming density is about 800-1000 tails/sq m. About 10 days before stocking the leech seeds, apply 300kg/mu of decomposed organic fertilizer, which can properly cultivate microorganisms and aquatic plants. To ensure bait for feeding the leeches, aquatic plants such as Hydrilla verticillata and Alternanthera philoxeroides can also be introduced.

5. Routine management

1. Feeding

(1) Leeches are omnivorous with a preference for animal food. They mainly eat microorganisms and floating algae in the water, and also eat snail and mussel meat, minced pork liver, etc. They also have the characteristic of liking to suck blood.

(2) During artificial rearing, pay attention to combining meat and vegetable ingredients. Livestock and poultry blood can be mixed with feed or grass meal, etc., and river mussels or snails can also be directly put in to reproduce.

(3) For feeding methods, pay attention to the four fixed rules: first, fixed time, feed once each morning and evening; second, fixed location, feed at the edge of shallow water in the field; third, fixed quality, choose fresh bait and remove residual bait in time; fourth, fixed quantity, adjust the feeding amount according to the situation, with the standard being that the leeches are full.

2. Fertilization: apply sufficient organic fertilizer to the rice field at one time at 3000kg/mu. When fertility is insufficient, apply rapeseed cake fertilizer at 10kg/mu, in small amounts multiple times. While topdressing, supplement leech bait, which helps save farming costs.

3. Medication: generally no medication is used. The rice field ecological cycle is used, and leeches have strong disease resistance, so diseases rarely occur.

4. Water quality: the water quality must be safe and pollution-free, the water layer should be maintained at about 20cm, change the water once a week, and add new water at the same time.

5. Escape prevention: do a good job of pond patrol every day. Once problems are found with the embankment, anti-escape wall, water inlet and drainage facilities, repair them in time to avoid leeches escaping and hiding.

6. Processing and sales: after about half a year of leech farming, they can be caught after the rice harvest. Catch the large ones and keep the small ones as seeds. After catching, put them into a container, then add 5%-10% salt water to kill them, rinse with clean water and dry in the sun before selling. The selling standard for good-quality dried leeches is uniform specifications, no impurities inside, and a moisture content below 20%.

6. Analysis of leech farming prospects

1. Leeches have the effects of promoting blood circulation and removing blood stasis, and treating dysmenorrhea. Their medicinal value is extremely high. From ancient times to the present, they have been used as a precious Chinese medicinal material and are a main medicinal component for treating cardiovascular and cerebrovascular diseases. As such diseases continue to increase in China, the use of leeches has also increased year by year.

2. Due to factors such as the environment and climate, wild leech resources are scarce. For example, Japan imports large quantities of leeches from China every year, and the market gap is large. It is a special farming industry with low investment and high benefits.

3. Leeches have strong vitality and can be farmed almost anywhere. They not only have low costs but also show quick results. Especially at present, artificial leech farming is still in its initial stage, with small numbers and small scale, and market supply falls short of demand. It is expected that in the next few years leeches will become a new type of agriculture and be widely farmed.