Growth Response of White Prawn, Penaeus indicus, to Dietary L-Carnitine

Abstract

Juveniles of Penaeus indicus were fed a biosynthetic product, L-camitine, at concentrations of 100 ppm (Tl), 250 ppm (T2), 500 ppm (T3), 750 ppm (T4) and 1,000 ppm (TS) in a fish meal-based supplementary feed having 40% protein. A diet without L-camitine supplement served as control (TO). The growth study was conducted for 120 d in nylon hapas, arranged in a brackishwater pond. AH diets with L-camitine produced significantly higher growth than the control (P<O.Ol). The diet containing 500 ppm camitine promoted maximum growth (14.82 ± 2.86 g) compared with the control (9.07 ± I.67 g). Feed conversion efficiency, assimilation efficiency and protein efficiency ratio were high in carnitine-fed prawns; optimum values were recorded for the 500 ppm treatment. Digestive enzyme (amylase, protease and lipase) activities were high in the mid-gut of prawns fed carnitine diets. RNNDNA ratios in the muscle and hepatopancreas of prawns under carnitine treatments were higher than the control. Total dry matter and protein contents of the body increased in prawns fed L-camitine. Lipid content decreased in all carnitine-fed groups with maximum value in the control (2.69%), indicating enhanced lipid catabolism, thereby sparing energy and protein for growth and anabolic processes.