Whiteleg shrimp ( Litopenaeus vannamei, synonym Penaeus vannamei), also known as Pacific white shrimp or King prawn or White shrimp, is a species of Dendrobranchiata of the eastern Pacific Ocean commonly caught or farmed for Human food.
Description
Litopenaeus vannamei grows to a maximum length of , with a
carapace length of .
Adults live in the ocean, at depths to , while juveniles live in
estuary.
The rostrum is moderately long, with 7–10 teeth on the dorsal side and two to four teeth on the ventral side.
The global production of white shrimp had increased to approximately 5 million metric tons, with a market value reaching USD 30 billion in 2018.
Distribution and habitat
Whiteleg shrimp are native to the eastern
Pacific Ocean, from the
Mexico state of
Sonora to as far south as northern
Peru.
It is a
euryhaline tropical shrimp species capable of growing in salinities ranging from 0 to 40‰,
with the optimal salinity for growth being between 15 and 25‰.
The optimal pH for white shrimp is approximately 7.56,
and dissolved oxygen levels should be maintained above 2.8 mg/L.
Whiteleg shrimp can grow in water temperatures ranging from 15 °C to 38 °C, with the optimal growth temperature between 22 °C and 35 °C; it is restricted to areas where the water temperatures remain above throughout the year.
Fishery and aquaculture
During the 20th century,
L.vannamei was an important species for Mexican
inshore fishermen, as well as for
Fishing trawler further offshore.
In the late 20th century, the wild fishery was overtaken by the development of
aquaculture production; this began in 1973 in
Florida using prawns captured in
Panama, that were used in hatcheries for larvae production.
In Latin America, the cultivation of L. vannamei expanded with improvements such as the availability of hatchery-produced larvae, advances in feed formulation, modernization of farming techniques, development of freezing facilities, and establishment of market distribution channels.
Around the beginning of the 21st century, Asia introduced this species in their aquaculture operations (changing from Penaeus monodon).
China, Vietnam, India and others have become major packers as well.
By 2004, the production of white shrimp had reached 1,116,000 metric tons, surpassing that of black tiger shrimp.
Litopenaeus vannamei have been cultivated indoors through a recirculating aquaculture system in Downey, California.
Weather effect
Normally, there are peaks of production during the warm El Niño years, and reduced production during the cooler La Niña years. The effect is on ocean caught as well as on aquaculture origin.
Diseases
Litopenaeus vannamei farming has been affected by several pathogens, which have caused significant economic losses in the shrimp aquaculture industry.
There are several known diseases.
Production of
L.vannamei is limited by its susceptibility to white spot syndrome,
Taura syndrome, infectious hypodermal and haematopoietic necrosis, baculoviral midgut gland necrosis, and
Vibrio infections.
Acute hepatopancreatic necrosis syndrome (AHPND), caused by
Vibrio parahaemolyticus, was initially referred to as Early Mortality Syndrome (EMS). It has caused significant economic losses in the white shrimp aquaculture industry.
and
Vibrio alginolyticus are also among the commonly found
Vibrio species.
In aquaculture, the use of antibiotics or chemical agents has been associated with environmental pollution and drug residue concerns. As a result, practices have increasingly shifted toward improving pond conditions and enhancing the immune response of white shrimp. Approaches such as water quality management, incorporation of probiotics into feed, and application of immunostimulants have been reported to be effective in reducing the risk of large-scale disease outbreaks.
Impact on nature
In 2010,
Greenpeace International added the whiteleg shrimp to its seafood red list.
This lists fish that are commonly sold in supermarkets around the world, and which have a very high risk of being sourced from unsustainable fisheries.
[ Greenpeace International Seafood Red list] The reasons given by Greenpeace were "destruction of vast areas of
mangroves in several countries, overfishing of juvenile shrimp from the wild to supply
, and significant human rights abuses".
[ In 2016, L.vannamei accounted for 53% of the total production of farmed crustaceans globally.]
Immune mechanism
Crustaceans primarily rely on non-specific immune responses,
-
Cellular immune responses
-
Humoral immune responses
See also
-
Macrobrachium rosenbergii, the giant freshwater prawns
-
Pandalus borealis, Canadian northern prawns
External links
