Use plastic greenhouses to raise early-bred prawn fry, culture the first crop of giant freshwater prawn from May to mid-August, then culture a second crop of giant freshwater prawn from mid-August to October; or culture the first crop of giant freshwater prawn from June to September, then culture one crop of oriental river prawn from October to May of the following year. In this way, the economic returns of pond prawn farming can be greatly increased.

Prawn farming: polyculture of giant freshwater prawn and whiteleg shrimp gives good returns

1. Building the culture pond

The culture pond should have an area of 8-10 mu, a slope ratio of 1:2.5, good water quality, abundant water supply, and a water depth of more than 2 m. For newly dug culture ponds, a 4-6 m wide prawn collection trench should be dug in the center of the pond bottom to facilitate concentrated harvesting. Build the inlet and drainage systems well using the high-irrigation, low-drainage design.

Giant freshwater prawn pond culture

2. Fry rearing

To raise two crops of giant freshwater prawn, plastic greenhouses must be built in advance. From late March to early April, buy early-bred prawn fry and give them intensive rearing, striving to reach a fry size of 3 cm by mid-to-late May. From mid-to-late May, buy mid-to-late-stage giant freshwater prawn and rear them in dedicated ponds; by around mid-August the fry can reach a size of 3 cm for stocking in the second crop. If the first crop is giant freshwater prawn and the second crop is oriental river prawn, buy giant freshwater prawn fry for stocking in mid-to-late May, buy oriental river prawn fry in early June, select a good rearing pond, set up several small net cages, and stock egg-bearing oriental river prawns; by the end of September the oriental river prawn fry can reach a size of about 3 cm.

Prawn farming: secrets to improving the survival rate of oriental river prawn fry during pond harvest and transport

3. Rational stocking

For raising two crops of giant freshwater prawn, stock 0.8-10,000 fry per mu for the first crop and 1-12,000 fry per mu for the second crop. For raising giant freshwater prawn in the first crop and oriental river prawn in the second crop, stock 2-25,000 giant freshwater prawn fry per mu, or 1-15,000 brood prawns per mu, and stock 1.5-20,000 oriental river prawn fry per mu. Before stocking, do a good job of cleaning and disinfecting the prawn pond, cultivating basic feed organisms, and transplanting aquatic plants. Choose a sunny morning for stocking, and be careful that the temperature difference is not too large.

Oriental river prawn culture

4. Feed feeding

For raising the two prawn species, compound feeds of the giant freshwater prawn and oriental river prawn series can be used respectively. For raising giant freshwater prawn, mainly feed clam, snail, and mussel meat, supplemented with compound feed, or mainly use the series compound feed and appropriately add small shrimp and small fish. Usually, the feed fed at the juvenile prawn stage is required to have a protein content of more than 35%, and at the adult prawn stage more than 32%. The daily feed amount is 5%-10% of the prawn body weight in the pond for giant freshwater prawn, and 3%-5% for oriental river prawn. The feeding in the evening is the main one, accounting for about 70% of the whole day's amount. During the day, feed is placed in the deep-water area; in the evening, it is placed in the water grass clumps in the shallow-water area, so as to achieve feeding at fixed times, fixed amounts, fixed quality, and fixed locations.

Prawn pond microbial EM bacteria to improve water quality

5. Water quality management

In May-June, during the initial stocking period of prawn fry or brood prawns, keep the pond water depth at 0.8 m; in the high-temperature season from July to September, fill the pond with water; in autumn, when there is much cloudy, rainy, and muggy weather, replace and add fresh water once every 7-10 days at 1/3 according to water quality conditions. At ordinary times, strengthen water quality testing and pond patrols.

Giant freshwater prawn pond culture

6. Timely harvesting

For raising two crops of giant freshwater prawn, start harvesting the first crop in early August and the second crop in early October; for raising one crop of giant freshwater prawn and one crop of oriental river prawn, start harvesting the giant freshwater prawn from mid-August onward, harvesting the large ones and leaving the small ones, and marketing them in batches; the oriental river prawn is harvested and marketed in May of the following year. Where conditions permit, a plastic greenhouse temporary holding method can also be adopted, selecting and keeping a portion of commercial prawns for sale around the Spring Festival when prices rise.

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