1. Site selection for pond construction: The leeward is needed for shelter from the wind, and the place with convenient irrigation and drainage and sufficient sunshine is also needed to build the farm. The leech culture pond has a width of 3m and a depth of 1- 1.2. The length can be determined according to the size of the site. It is best to smooth the aquaculture pond with cement to prevent water leakage and facilitate aquaculture management. The entrance and exit of the pond are diagonally arranged, and the bottom of the pond should be high in the north and low in the south, which is convenient for irrigation and drainage. Loose sandy soil rich in humus is used around the pond for grasshoppers to lay eggs. Build a platform 0.2 meters above the water surface in the middle of the pond to keep the pond moist, and put some stones and branches at the bottom of the pond for grasshoppers to inhabit.

2. Water source requirements: the cultivation of leeches needs a suitable water source, which directly affects the survival, development and reproduction of leeches. Compared with wild leeches, the density of artificially cultured leeches is much higher, and the wells should be changed frequently during the feeding process to prevent the pollution of chemical fertilizers and pesticides. Especially in the high temperature season from July to August, it is necessary to ensure that the water inlet and outlet are unblocked, the water quality is fresh and there is a certain oxygen capacity.

3. Selection of leeches: Selection of leeches requires individual hypertrophy, preferably more than 0/2g per leech/kloc, strong fluidity, smooth body surface, bright color and no scar, and stocking density of 20-25kg (2,000-2,500 leeches) per mu. The varieties of leeches are selected according to local conditions.

4. Hatching of leeches: Generally leeches can breed and lay eggs above 1 1℃, and young leeches hatch after 16-25 days. Keep quiet near the pond when laying eggs. So as not to disturb the oil leeches that lay eggs and cause empty egg cocoons. Avoid walking on the platform and breaking the cocoon with rabbits during incubation. After 3 days, the hatched leeches can feed on the blood of mussels and snails by themselves. So put enough feed. Generally, 20 kilograms of snails and mussels are put into every thousand leeches, and the blood clots of livestock are fed once a week to let them eat freely. However, attention should be paid to cleaning up the remaining food such as blood residue at any time to keep the water quality clean.

5, leeches wintering: leeches have strong cold resistance and are generally not easy to freeze to death. Under natural conditions, when the temperature is lower than 10℃, it will stop eating and get into the mud for the winter. Artificial culture can cover the pond with straw and other things to keep warm and help leeches survive the winter naturally. The method is time-saving and labor-saving, and is suitable for large-scale commercial leech culture. Leeches can also be concentrated in plastic film sheds for the winter and fed once every half month. This method can make leeches grow and move normally, and they can mate and lay eggs when the temperature rises slightly.

6. Natural enemies and disease prevention of leeches: attention should be paid to natural enemies in leech culture. Voles, frogs, weasels and snakes are all natural enemies of leeches, and their resistance is weak, as are mollusks. Hui power grid can be used for prevention and control and tool trapping. Leech farming is less sick, leeches have strong vitality and are basically free from disease. The key is that the water source is better. As long as the water source is not polluted by chemical fertilizers, pesticides and saline-alkali solutions, the water inlet and outlet are kept unobstructed, the food is fresh, the feed residue is removed in time, and the water is changed frequently, the leeches can be kept well, otherwise skin diseases and intestinal diseases may occur.