Freshwater Farming Techniques for Whiteleg Shrimp (Litopenaeus vannamei) and Treatment of White Feces Disease

AbstractPond: mud-sand bottom, water depth about 2 m, inlet filtered with 60-mesh silk gauze. Seedstock: use fully desalinated shrimp fry, turn on the aerator the day before stocking, and release a small number of test shrimp before stocking the fry in large quantities. Feed: fixed times and amounts, fixed spots and quality, small amounts given frequently, adjusted as needed. Water quality: add 50 ppm crude salt to the pond before stocking, then add crude salt as appropriate afterwards. Disease prevention: 30-60 days after stocking is the high-incidence period for viral diseases, so actively prevent and treat whiteleg shrimp diseases.

The whiteleg shrimp originates from the Pacific coast of South America and is one of the three finest shrimp species with the highest farming output in the world known to date. It is deeply loved by everyone. Below we will learn about freshwater farming techniques for whiteleg shrimp, hoping to be of some help to the many farmers.

Freshwater Farming Techniques for Whiteleg Shrimp

1. Pond conditions

The farm area is 2-3 mu (adjustable according to scale), using a mud-sand bottom, with water depth controlled at about 2 m, and the inlet filtered with 60-mesh silk gauze. Before stocking, leave 50 cm of water, use 110 kg/mu of quicklime and 32 kg/mu of tea seed cake for pond clearing, and install one 1.5 kW impeller aerator.

2. Seedstock stocking

Stock fully desalinated shrimp fry about 2.1 cm in length. Note that fully desalinated whiteleg shrimp fry must be used; it is best to visit the hatchery a few days before purchase to observe the desalination status of the fry, for greater peace of mind. The day before stocking, turn on the aerator to increase oxygen, and release a small number of test shrimp before stocking the fry in large quantities. The stocking density is 40 shrimp per sq m. One month after stocking the shrimp fry, release 30-40 silver carp and bighead carp of 0.25 kg each.

3. Feed

Feeding of whiteleg shrimp follows the principles of “fixed times and amounts, fixed spots and quality, small amounts given frequently, adjusted as needed.” Generally, three to four feeding trays are set up in the pond. For half a month after stocking, feed four times a day, at a daily feeding rate per 10,000 shrimp fry of 5 eggs, 0.2 kg of peanut bran, 0.75 kg of small fish and 0.3 kg of shrimp feed. After 15 days, feed three times a day, mainly with compound feed, at a feeding amount of 30-40% of shrimp body weight, appropriately supplementing natural food; in the later stage, the feeding amount gradually decreases as the shrimp grow.

4. Water quality

Although the shrimp fry are desalinated, they still have seawater habits, so 50 ppm crude salt should be added to the pond before stocking, and crude salt added as appropriate later. Within one week after stocking the shrimp fry, maintain a water level of about 50 cm, then increase it by 5 cm each day until the water depth reaches about 160 cm. Change 20% of the water every 4-5 days, and apply 12-15 ppm quicklime every 10-15 days. To provide a good living and growing environment for the shrimp, it is best to transplant some water hyacinth half a month after stocking the fry, covering about 20% of the area, and fix it with moso bamboo to prevent it from spreading everywhere.

Treatment of White Feces Disease in Whiteleg Shrimp

I. Treatment methods

1. First, perform a 360-degree bottom improvement and detoxification (10 kg zeolite powder + 2 L strong organic acid for 2 mu).

2. Then, hours later, feed 200 g of Clostridium butyricum mixed with 80 jin of feed for 3 days; in severe cases, splash 200 g of Clostridium butyricum over 2 mu.

3. After an interval of one day, perform another round of 360 bottom improvement and detoxification, and use Super Energy + Bacillus to supplement beneficial bacteria in the water and enhance the water's digestive capacity.

II. Prevention methods

1. Strengthen management: patrol the pond at least three times a day; when checking the feeding trays, observe the shrimp's feeding, vitality and feces; actively follow weather forecasts so as to take preventive measures against climate changes in time.

2. Feed reasonably: feed an appropriate amount of Clostridium butyricum; the feeding amount and number of feedings should be reasonable.

3. Protect the liver and strengthen the intestines: enhance the nutrition of whiteleg shrimp, and supplement minerals and vitamins in time.

4. Stabilize water and improve the bottom: regularly disinfect the pond bottom.

Disease Prevention Techniques for Whiteleg Shrimp

For whiteleg shrimp, 30-60 days after stocking is the high-incidence period for viral diseases; during this period, use medication according to the prevention measures for different diseases:

1. Biological disease prevention: mainly use active microecological preparations or bottom quality improvers to regulate water quality, and add active feed microorganisms, FRC—Vitality Source additive, etc. to the feed, which can effectively improve the shrimp's intestinal function, increase their absorption rate of feed, inhibit the occurrence of pathogens, enhance the body's immunity, and promote shrimp growth.

2. Chemical disease prevention: every 10-15 days, splash disinfectants of the hydantoin class such as bromochlorohydantoin, dibromohydantoin and dichlorohydantoin over the whole pond once, at a dosage of 0.2 ppm-0.3 ppm. For oral administration, frequently add shrimp growth promoters, pure Chinese medicine preparations, FRc—Vitality Source additive, immune enhancers and other green products to the feed. These can enhance the shrimp's immunity, remove harmful substances from the shrimp's body, and achieve the effect of preventing and treating diseases.

Disease Characteristics of Farmed Whiteleg Shrimp

1. The vitality and swimming ability of whiteleg shrimp weaken. Generally, healthy disease-free shrimp usually inhabit the middle and lower layers of the farming water body or near the bottom, and are not easily seen; sometimes some shrimp groups can be found on the pond embankment, but they move actively, swim quickly and have strong jumping ability.

2. The food intake of whiteleg shrimp decreases or stops, and growth becomes slow. For healthy disease-free shrimp groups, active competition for food can be seen at feeding time; after half an hour, sample and check, and more than 80% of the shrimp have full stomachs and intestines; after continuous observation for 3-5 days, good growth and robust shrimp bodies can be seen.

3. The body color and gills of whiteleg shrimp become abnormal. Healthy disease-free whiteleg shrimp have a transparent or semi-transparent body; especially for juveniles and immature shrimp, the body color is normal and bright, with no dirt, algae, protozoa or other attachments on the body surface, and through the carapaces on both sides, the gills are clean and clearly visible.

From the above, it can be seen that the farming techniques for whiteleg shrimp are relatively simple, and this shrimp has many fine characteristics such as fast growth and strong disease resistance, so farming this shrimp can bring relatively significant economic benefits.