Detailed Explanation of Giant Freshwater Prawn (Macrobrachium rosenbergii) Farming Techniques and Analysis of Farming Prospects
AbstractPond: The pond bottom should be flat and the water quality fresh, with escape-prevention facilities properly built. Pond clearing: 20-30 days before stocking, drain the pond water, remove excess sludge, and disinfect the pond with quicklime or similar. Aquatic plants: Plant water spinach, alligator weed, eelgrass, etc. along the water line 70 cm up the pond slope around the pond. Stocking: Release shrimp fry when the water temperature is stable above 20°C, at 20,000-25,000 per mu. Feed: Mainly artificial feed combined with pelleted feed. Management: Patrol the pond morning and evening, and deal with any disease promptly.
As people's living standards rise, many have increasingly strict and demanding requirements for quality of life, especially when it comes to food. Shrimp is one of the ingredients people greatly enjoy, nutritious and delicious, and favored by many. There are many kinds of shrimp, and today we will take you through everything about the giant freshwater prawn.
Giant Freshwater Prawn Farming Techniques
1. Pond preparation: The pond area for shrimp farming should preferably be 1000-5000 sq m, with an effective depth of 1.5-2.0 m, a flat bottom, fresh water quality, convenient drainage and irrigation, good water retention, and fairly gentle surrounding slopes, while escape-prevention facilities should also be properly built.
2. Pond clearing and disinfection: 20-30 days before stocking the shrimp fry, drain the pond water, remove excess sludge, repair the pond banks, and use 75 kg of quicklime per mu, or bleaching powder, bleaching powder concentrate, or similar agents, to thoroughly clear and disinfect the pond.
3. Aquatic plant cultivation: After pond disinfection, plant water spinach, alligator weed, eelgrass and other plants along the water line 70 cm up the pond slope around the pond to form a grass belt about 1 m wide with a plant spacing of 0.2 m, covering about 15-20% of the pond's total area.
4. Fry stocking: When the pond water temperature is stable above 20°C, the shrimp fry can be released. It is best to stock juveniles that have been intermediate-cultured in a greenhouse or warm shed, with a size above 1.5 cm and a survival rate above 75%, at a stocking rate of 20,000-25,000 per mu.
5. Feed feeding: The giant freshwater prawn is omnivorous but leans toward animal food, so feeding should mainly use artificial compound pelleted feed with a crude protein content of 35-40%, appropriately supplemented with chopped small trash fish, snail meat, mussel meat and other fresh live feed.
6. Daily management: Persist in patrolling the pond morning and evening, observe the shrimp's feeding, molting, growth and other activities, pay attention to changes in water quality and water temperature, promptly remove residual feed and debris from the water, keep patrol records, and deal with any disease promptly.
Farming Prospects of the Giant Freshwater Prawn
The giant freshwater prawn is native to tropical regions and has high temperature requirements during its growth period. In the middle and lower reaches of the Yangtze River, stocking begins in May-June and harvesting takes place in October, so it comes to market in a fairly concentrated period, and at other times the giant freshwater prawn is generally unavailable. To increase income, some places have begun using greenhouses to farm shrimp, greatly advancing the harvest time and multiplying the benefits.
The giant freshwater prawn is nutritious, delicious, large in size, and sells well on the market. It is omnivorous, grows fast, and is easy to farm, with good market prospects. It has now become one of the key special-quality aquatic products developed in China, and not only has pond farming made considerable progress, but rice-field farming has also been successful. At present, giant freshwater prawn farming is in a stage of development, and giant freshwater prawn farming has broad prospects.
Cost Analysis per Mu for Giant Freshwater Prawn Farming
Cost indicators: below 4,200 yuan per mu (below 14 yuan per kg of shrimp), of which:
1. Disinfection and pond clearing costs: 100 yuan/mu;
2. Shrimp fry: calculated at 250-30 yuan per 10,000 fry, 40,000 fry is 1,200 yuan/mu;
3. Feed: The feed coefficient is 2·2-2·3; using self-mixed feed at 3 yuan per kg, the feed cost is 1,980 yuan/mu;
4. Other costs: 920 yuan/mu, of which: electricity 150 yuan/mu; pond rent 600 yuan/mu; large fish fry: 70 yuan/mu (40 per mu, 0·25 kg each); hired labor and depreciation 100 yuan/mu.
Common Diseases of the Giant Freshwater Prawn and Their Prevention
1. Gill rot disease
Symptoms: The gill filaments swell, turn gray, and become brittle; in severe cases the gill tips ulcerate, and the ulcerated and necrotic parts shrink or fall off. In some gill filaments, a dark brown dividing line forms at the boundary between the ulcerated tissue and the tissue not yet ulcerated.
Prevention and treatment: First use Zhongduqing + water base to clear the gills and expel toxins, make the water body permeable, and strengthen the shrimp's constitution. In the evening use Diduxiao + Lemi oxygen, once a day, for 2 consecutive times.
2. Ciliate disease
Symptoms: A large number of ciliates (such as Epistylis, Carchesium, Zoothamnium, etc.) parasitize the body surface of diseased shrimp, and the body surface appears brownish-yellow and fluffy, affecting the diseased shrimp's feeding and molting, and in severe cases can cause the shrimp to die. The main cause is water that is too fertile, allowing Epistylis, Carchesium, Zoothamnium and others to multiply in large numbers.
Prevention and treatment: Change the water regularly to keep the water quality fresh; disinfect the water body with 0.4 ml/kg bromochloro hydantoin; splash with a mixture of copper sulfate and ferrous sulfate (5:2) at a concentration of 0.7 mg/kg.
The giant freshwater prawn is an ideal farming species because it has many advantages, such as fast growth, a short growth cycle, and ease of rearing. Of course, for farmers, the most important thing is still its high yield, which can bring relatively substantial returns.