Captive maturation, breeding and seed production of Pink ear emperor, Lethrinus lentjan (Lacepede, 1802) (Family: Lethrinidae) in recirculating aquaculture system (RAS)

Abstract

Pink ear emperor, Lethrinus lentjan (Lacepede, 1802), belonging to the family Lethrinidae (oder: Perciformes) is an important food fish in India, Arabian Gulf and other South East Asian countries. The present communication gives detailed information on its captive broodstock maturation in RAS, natural spawning, larval rearing and seed production for the first time. Fertilized eggs (714.21 ±11.91 μ) were transparent, pelagic, non-adhesive with single oil globule (146.63± 3.51μ). Green water system was used for larval rearing. Size of hatchling ranged from 1355.1 μ to 1534.6 μ and mouth (110 - 148.2 μ) opened on 2nd dph . Larvae were reared using copepods, rotifer, artemia and micro diet. Squamation and intense pigmentation on the body began by 22 dph and by 25-30 dph larvae started moving from pelagic to benthic realm. Larvae became juvenile (length - 19.2 mm; weight - 0.096 g) after 35 dph resembling the adult fish colourations and by 46 dph, they attained an average body length of 27.83 mm and average body weight of 0.276 g. Fishes spawned throughout the year in RAS without any hormonal manipulation. Average percentage survival at seed stage was 2.85 ±1.41.