Freshwater aquaculture (2+1)

Unit 4 - Cultivable fish and their culture methods

4.1. Culture of indian major carps and exotic carps
Carps are major source of animal protein for millions of people in Asia. World cyprinid aquaculture production in 2009 was 22,228,344 metric tons valued at USD 29,399,045. They are the most cultured species in the world with 40% production by volume. The major countries producing carps through aquaculture are China and India.
Carps belong to the family Cyprinidae which is typically a freshwater group with very wide distribution. They are distinguished by the presence of pharyngeal teeth in one to three rows with not more than eight teeth in any row. Lips are usually thin and an upper jaw that is usually bordered only by premaxilla.
There are about 1600 species in the family cyprinidae making it the largest family of fish. Despite large number of species of carps only 29 species of carps is cultured globally (FAO statistics list the production figure for 29 species only). There are only six species which are cultured on a large scale. They are grass carp, silver carp and common carp in China and Catla, rohu and mrigal in India and elsewhere. The former three species are termed the Chinese carps and the later three as the India major carps. Together they are called major carps since they grow to relatively large size.

Biology
Cultured carps are all riverine , typically found in large river systems. The food habits of species differ from each other.
Summary of feeding habits of the major Carps

Species	Feeding habit
Silver carp	Zoo- and phytoplankton, filter feeder, prefers phytoplankton, surface feeder.
Grass carp	Omnivorous, prefers higher aquatic plants and submerged grasses
Catla	Plankton feeder, prefers zooplankton and surface feeder
Rohu	Omnivorous planktophage; predominantly a column feeder
Mrigal	Omnivorous, prefers detritus, predominantly a bottom feeder
Common carp	Omnivorous, predominantly feeds on benthic worms; a bottom feeder

All the major carps grow to about 1m in length. Generally Chinese carps grow to a larger size than Indian major carps. Under culture conditions they are harvested in their second or third year, often at a weight approaching 2-3 kg.