Artificial breeding methods for freshwater shrimp: water quality cultivation is key

Shrimp farming

    Wild-caught freshwater shrimp (oriental river shrimp) can be artificially bred. There are two breeding methods: one is to directly catch small shrimp for grow-out; the other is to catch egg-bearing shrimp and put them into a pond, let them naturally spawn and hatch larvae in the pond, and then rear them into small shrimp for grow-out. The key points of grow-out are introduced as follows:

    1. Environmental conditions for breeding: The water used for oriental river shrimp breeding must meet the water quality standards for fishery waters, and must be clean with sufficient oxygen. There should be no large harmful organisms in the breeding pond. The pond water depth is 1.2—1.5 m, the bottom mud should be minimal, and the substrate should preferably be hard. The oriental river shrimp is not good at swimming and has negative phototaxis. During the day it mostly hides in dark gravel or aquatic plants, that is, it hides by day and comes out at night, emerging at night to forage. It spends most of its time resting on the bottom or on aquatic plants and other clinging objects, and likes to inhabit slow-flowing shallow shoals along the banks where aquatic plants grow thickly. Therefore, breeding oriental river shrimp requires a sufficient number of attachment objects; aquatic plants can be planted at the pond edges or netting sheets can be hung. However, under artificial breeding conditions, the oriental river shrimp can also feed during the day.

    2. The oriental river shrimp has a very omnivorous diet. From the larval stage to the adult shrimp, it feeds on zooplankton, algae, cladocerans, copepods, small aquatic insects, organic debris, filamentous algae, attached algae, invertebrates, and so on, but it prefers animal feed. Under artificial breeding conditions, compound feed can be used, and it especially likes animal feed such as snail and mussel meat, earthworms, small trash fish, maggots, and silkworm pupae, so it is better to appropriately add some animal feed during the breeding process.

⟧    3. According to observation and investigation, the lifespan of the oriental river shrimp is generally only a little over one year, and the longest is only a little over 2 years (male shrimp 16—17 months; female shrimp 26—27 months). Most people now believe that oriental river shrimp hatched in May—June die one after another after completing reproduction in July and August of the following year. Many farmers stock several dozen kilograms of egg-bearing shrimp in May, and by the end of the year they cannot catch large shrimp, only small shrimp, for this reason. Therefore, when stocking egg-bearing shrimp for breeding, after the shrimp finish spawning, the large shrimp should be caught and sent to market in a timely manner.

    4. The oriental river shrimp has two spawning peaks. Late spring and early summer is one spawning peak, formed by the spawning of older shrimp after overwintering; the autumn breeding peak is formed by the spawning of part of the first-generation young shrimp of that year. Therefore, whether to carry out autumn breeding should be decided according to one's own breeding conditions and environment, and from the perspective of balanced market supply and improving yield and efficiency, overall planning should be carried out, and the advantage that the oriental river shrimp can naturally overwinter should be brought into play.

    5. If breeding starts from larvae, then early water quality cultivation is key. A large amount of zooplankton needs to be cultivated with organic fertilizer for the larvae or young shrimp to feed on, so as to improve the survival rate of rearing and breeding. Once the small shrimp stage is reached, artificial feed or compound feed can be fed. After 50—60 days of rearing, the hatched larvae generally can reach a body length of 2.5—3 cm, and some female shrimp mature; by October—November, male shrimp can reach 4—5 cm. Therefore, during the breeding process, timely arrangements for catching and sending to market should be made according to the growth of the shrimp. Sending large-sized shrimp to market is beneficial to the growth of the small shrimp left in the pond.

    6. In order to improve the growth speed and pond-exit size of oriental river shrimp breeding, it is best to breed in two stages, that is, from larvae to 1—2 cm small shrimp seed, and then from small shrimp to adult shrimp. If conditions permit, three-stage breeding can be carried out, that is, larvae —— small shrimp seed about 1—2 cm in body length —— large shrimp seed over 3 cm in body length —— adult shrimp. Staged breeding can also increase the survival rate of breeding.

    7. Reasonable stocking: For monoculture of oriental river shrimp, shrimp seedlings are usually stocked from mid-June to mid-July each year, with 60,000—80,000 tails per mu; if small shrimp are stocked, the number can be appropriately reduced. For polyculture of fish and shrimp, from mid-July to mid-August each year, stock 15,000 tails per mu of shrimp seed about 2 cm long. If egg-bearing shrimp are stocked for breeding, stock 25—30 jin of egg-bearing shrimp per mu. In the second year, you may also consider carrying out two-crop pond (two-season) breeding. In addition, silver carp and bighead carp summer fingerlings or fingerlings should be stocked as a supplement in the shrimp breeding pond (by the mid-rearing period, stock 1,000—1,500 larger current-year fingerlings in the adult shrimp pond).

    8. Harvesting: The main harvesting methods include ground cage nets, shrimp traps, and dip nets, or driving and catching along the pond edges where aquatic plants are present. Generally, rotational harvesting should begin in September, catching the large and leaving the small, and commercial shrimp reaching over 4.5 cm are caught and sent to market one after another.