1. Breeding pond preparation The leeching breeding pond is generally built in a place sheltered from the wind, with convenient drainage and irrigation, sufficient water supply, and fresh water without pollution. Pool width 5 ~ 8m, water surface width 3 ~ 5m, length of about 10m, water depth can be maintained 0.5-1m. A platform with a width of 0.5-1 m is set around the water surface. The overflow of the pond is lower than the platform by 3 to 5 cm, and the platform is 2 to 10 cm above the water surface. The soil used for the platform is sandy loam rich in humus, which is convenient for tapping holes in spawning and spawning. In general, the platform should prevent water accumulation, prevent drought, and be flooded after rain. Pond disinfection should use strong chlorine and other drugs, can not use quicklime and other harmful drugs.
Second, the choice of species and stocking choices robust and thick, lively and lively, hand-touch can quickly shrink into a mass, 2 winter age, weight 20 ~ 30g as a seed pods. The time for the species to enter the pond is in the middle of April. The stocking amount depends on the area of ​​the platform and the capacity of the water body. In general, 1.5 kg of seeds and about 40 to 50 seeds can be placed per square meter of platform. Before entering the pool, the species should be disinfected with bleaching powder: the concentration of the liquid is 8 ~ 10mg/l, the water temperature is. At 10~15°C, sterilize for 20-30 minutes. The pool should have sufficient snails, river clams and other food organisms for feeding, and the pool water quality should be kept cool.
Third, the breeding of young fleas Anthropods are linked to animals, hermaphrodites, allogeneic mating, in vivo fertilization, spawning and hatching cubs. Each species has both male and female reproductive organs.
1. When the mating leeches are mated, the two species of breams are head-to-head in the opposite direction, and the male gonopores face each other's female gonopores to complete fertilization.
2. One month after spawning and brooding, the species began to spawn. Secretion of two layers of mucus from the gonopore, the formation of the external ovary wall, wrapped around the genital hole, the eggs produced from the female gonad in the cavities between the wall and the body, and secrete protein solution to the quail. The parent body gradually withdraws from the back to form an oval egg, the size of the egg is generally 22 ~ 33mm15 ~ 24mm, weighing 1.1 ~ 1.7g. The egg pods harden in the soil layer in the platform for several hours, and the outer layer of the gingival wall foams and air-drys to become a honeycomb or sponge-like protective layer. Water can be spawned 1 to 2 times a year and 1 to 4 spawns at a time. During the spawning season, the environment should be kept quiet to prevent the species from being frightened and fleeing, resulting in empty space.
3. The hatching species will be caught after spawning and the breeding pond will be converted into a hatchery nursery pond. The eggs are naturally hatched. After 11 to 25 days under the proper temperature conditions, the hatchlings can hatch. Each egg can have 15 to 35 pups, and the majority are 20. The newly hatched cubs are yellow, and there are 7 purple-gray vertical stripes on both sides of the back of the body. As the larvae grow, the color gradually changes, forming 5 dark vertical stripes. The young hatchlings are hatched within 2 to 3 days and live on their own yolks. After 3 days, they are allowed to feed freely. They mainly take blood and sap from snails and river clams. After 15 days, they reach 1.5 cm body length and can be divided into pools. Feeding.
(277605 Fu Village Fishery Technology Station, Weishan County, Shandong Province)
The leech, commonly known as the leech, has high medicinal value and has a large market demand, while the amount of natural resources is decreasing, and artificial breeding is imperative. The artificial breeding techniques of leeches are briefly described as follows: