Giant freshwater prawn

Giant freshwater prawn

　　Also known as whiteleg shrimp, Malaysian prawn, money prawn, or vannamei shrimp, it is often hailed as the "king of freshwater shrimp." Its origin is concentrated along the coast of Ecuador and it is currently one of the three most farmed shrimp species in the world. It has a thin shell, plump body, tender and delicious meat, and is highly nutritious. In addition to the typical flavors of freshwater shrimp, mature giant freshwater prawns have their cephalothorax filled with gonads, offering a uniquely rich and savory taste similar to crab roe. Each 100 grams of shrimp meat contains 20.6 grams of protein, 0.7 grams of fat, and various vitamins and essential trace elements required by the human body, making it a high-protein aquatic product. When consumed fresh, it can be prepared in dishes such as braised prawns, pan-fried white prawns, sautéed shrimp pieces, lute prawns, or stir-fried shrimp. Processed forms include dried shrimp and shrimp chips.

　　 Morphological Characteristics

　　 The body is large and bluish-brown. Each abdominal segment has a pair of appendages, with the tail appendages modified into a tail fan. The cephalothorax is thick and large, while the abdomen gradually tapers toward the rear. The cephalothorax includes six head segments and eight thoracic segments, enclosed by a single outer shell. The abdomen has seven segments, each enclosed by its own shell. Appendages come in pairs per segment and vary significantly—from front to back, they consist of two pairs of antennae, three pairs of mandibles, three pairs of maxillipeds, five pairs of walking legs, five pairs of swimming legs, and one tail fan. Adult prawns are generally larger in males than in females, with the largest males reaching up to 40 cm in length and weighing 600 grams, while females can reach 25 cm in length and weigh 200 grams. The second pair of walking legs in males is particularly large and appears azure blue.

　　 Production Areas and Seasons

　　 Originally from the Indo-Pacific region, it inhabits various types of freshwater or brackish water environments. Since the 1960s, it has been introduced and farmed in various countries and regions across Asia, Europe, and the Americas. It was introduced to China from Japan in 1976 and is now primarily cultivated in over ten southern provinces (municipalities and autonomous regions), with the fastest development in Guangdong.

　　 Biological Characteristics

　　 The giant freshwater prawn is a fast-growing, widely feeding, and highly nutritious economic shrimp species. It grows large, reaching up to 40 cm and weighing 600 grams, and originates from Southeast Asia. In pond farming, the shrimp usually appear grayish-yellow, are not tolerant to low temperatures, and thrive at an optimal water temperature of 20–34°C. They require high levels of dissolved oxygen in the water. As omnivorous crustaceans, they prefer animal-based food. The feed used in artificial breeding should contain about 37–38% crude protein, of which approximately 20% is animal protein and 17–18% is plant protein. Newly hatched giant freshwater prawns measure 1.7–2.0 mm in length and can grow to around 3 cm in just two months. Juveniles around 3 cm in size, when raised for five months, can reach an average weight of about 30 grams.