Detailed Explanation of Leech Breeding Methods and Technical Key Points

Summary Rearing pond requirements: Ponds, ditches, and paddy fields can be modified for use; the area is determined by the number of leeches being raised, and gauze netting must be installed at the water inlet and outlet. Breeding requirements: The stocking density is about 80,000 leeches per mu; some floating plants can be grown in the pond for shade and egg-laying. Daily management: Keep the water temperature between 15-30°C and ensure water quality. Feed management: Put in snails and shellfish daily in measured amounts; once a week, a wooden block with poultry or livestock blood clots can be placed in the water, but it must not be left for more than 2 days.

I. Rearing Pond Requirements

Leech breeding cannot be done without building a rearing pond. The rearing pond can be modified from a pond, ditch, or paddy field. If built artificially, it is best to build a rearing pond about 2 m high, with a water depth of about 1 m, a width of about 3 m, and no particular limit on length. At the water inlet and drainage outlet, netting should also be made into barriers to prevent the leeches from escaping.

II. Breeding Requirements

1. During leech breeding, about 80,000 young leeches can be stocked per mu, and about 20 kg of breeder leeches can be stocked.

2. To give the leeches a better living environment, some stones, branches, and so on can be placed at the bottom of the pond, and aquatic vegetation such as wild rice stem, lotus root, aquatic grass, and cattail can also be planted on the water surface. These plants can serve as habitats for the leeches, and the leeches can also lay eggs on them, while also providing some shade.

3. At the same time, some manure water can be put into the rearing pond to cultivate plankton, regulate water quality, and increase the humus content at the bottom of the pond, which is beneficial to the growth of the leeches.

III. Daily Management

During leech breeding, the water quality in the pond must be kept good. At the water inlet, strict precautions must be taken against pollution of the water source by pesticides and chemical products, and spring water that is too alkaline must not be used to breed leeches. The water temperature must also be well controlled. Well water with too low a temperature is not suitable for breeding leeches. If spring water is used, it can only be used after its water temperature has risen.

However, in summer, special attention must also be paid to the water temperature, because if the water temperature is too high, it will affect the growth of the leeches. To avoid excessively high water temperature caused by direct sunlight on the water surface, some shade-providing plants need to be grown beside the pond and the water changed frequently, so that the water temperature is maintained between 15-30°C.

4. Feed Management

Leech feed includes snails, shellfish, grass shrimp, animal blood, and so on. When feeding, it is not suitable to feed too much or in excess. For about every 100 sq m of water surface, put in about 5 kg of field snails. Once a week, a wooden block with blood clots can be placed in the water; the blood clots are poultry or livestock blood clots, and no salt needs to be added. In addition, the blood clots must not be left for more than 2 days.

5. Reproduction Management

Leeches have particularly strong reproductive and regenerative abilities. The leech egg-laying period is from early May to September, and the eggs hatch into young leeches after about 20 days. Leeches also grow very quickly. If they are raised properly, with rich nutrition and a good water quality environment, they can grow about 2 cm per month, and by autumn, around October, they can be raised into adult leeches.