The method of raising earthworms in pits

Feed is an important material basis and restricting factor for breeding famous, special and high-quality aquatic products, which is related to the success or failure and benefit of breeding varieties. Water earthworms reproduce rapidly and have high nutritional value (62% of crude protein in dry matter, 35% of essential amino acids and 98% of nitrogen recovery). It is a favorite food for many aquatic animals in the seedling stage. it is also the main food for benthic fish such as Sturgeon, fish danger, common carp, crucian carp, Loach, baby fish and rice field eel. Among the aquatic earthworms, the species suitable for culture are Sue's tail Gill worms and Huo's water worms. Raising water earthworms can provide long-term and stable high-quality animal feed for cultured aquatic products, reduce breeding costs, and improve breeding efficiency and quality. A simple and convenient pit culture method of water earthworms is introduced here.

I. the living and breeding habits of water earthworms

The individual of water earthworm is small, about 100 mm long, but the population yield is higher. The difference between tail Gill worms and water filament worms is that the former has tail gills, the tail is often exposed to mud, breathes with the water swing, and trembles faster during hypoxia, while the latter has no tail gills. Water earthworms like to live in the silt of micro-mud waters rich in organic matter, generally lurking at 10 cm ~ 25 cm under the mud surface, and hidden in the mud at low temperature. Water earthworms like dark fear of light, can not be exposed to the sun, eating soil to absorb organic humus, bacteria, algae for a living. After 2 months, the earthworm was sexually matured, hermaphroditic, allogeneic fertilization, and the eggs were enclosed in a cystic cocoon composed of transparent glial membrane. Generally, a cocoon contains 1 to 4 eggs, and most of them contain 7 eggs. During the reproductive period, each adult can expel 2-6 cocoons. When the water temperature is 22-32 ℃, the incubation period is generally 10-15 days, and the life span of artificial culture is about 3 months.

2. Pit cultivation method

1. Pit condition

The construction of an ecological environment suitable for aquatic earthworms requires micro-running water, loose soil, rich humus, avoiding light and so on. The pit can be newly excavated or rebuilt using puddles connected with the ditches, with an area of 3 to 5 square meters (3 ∶ 1 to 5 ∶ 1), with a water depth of 20 to 25 centimeters, with a bottom of loess or concrete with good water retention at the bottom and set into the drain. In general, the inlet and outlet should be separated, with one end entering the water and the other end draining. Before the introduction into the pit, it is also necessary to cultivate the sediment, it is best to dig the fertile fish pond mud, spread at the bottom of the pit, 10 cm thick, and then add 7.5 kilograms of livestock and poultry manure or farm manure per square meter, and finally add fermented cake, bran, bran dregs and so on.

two。 Introduction into the pit

The amount of introduction depends on water quality, mud quality, source of manure and season. The fertilizer source and mixed feed source are sufficient, the introduction amount is large, and the yield is high. Generally, 0.25 kilograms of worms are planted per square meter. After 30 days of cultivation, the daily harvest per mu can reach 10 kilograms, with a maximum of 48 kilograms.

3. Administration and Management

Maintain micro-running water to make the water fresh, high dissolved oxygen, accelerate the escape of metabolites and increase the feeding and growth of earthworms. In general, the velocity of the current is 2-8 cm / s. The speed should not be too fast, if the current is too fast, it will wash away nutrients and cocoons, affecting output. Earthworms should be fed every 2-3 days after introduction. If concentrate feed is used, the feed coefficient is about 2.6, and if pig and cow dung is used, the feed coefficient is 7.8-10.4.

4. Harvest

The water flow can be reduced or cut off at night, resulting in a lack of oxygen in the pit the next morning or in the morning, and the water earthworms will be forced to float in groups on the mud surface or on the surface of the water.