Jayaprakas, V. C. Sambhu-1996
Asian Fisheries Science, 9: 209-219
Abstract:
Juveniles of Penaeus indicus were fed a biosynthetic product, L-carnitine, at concentrations of 100 ppm (Tl), 250 ppm (T2), 500 ppm (T3), 750 ppm (T4) and 1,000 ppm (T5) in a fish meal-based supplementary feed having 40% protein. A diet without L-carnitine supplement served as control (T0). The growth study was conducted for 120 d in nylon hapas, arranged in a brackishwater pond. All diets with L-carnitine produced significantly higher growth than the control (P<0.01). The diet containing 500 ppm carnitine promoted maximum growth (14.82 +/- 2.86 g) compared with the control (9.07 +/- 1.67 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. RNA/DNA 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-carnitine. 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.
(Department of Aquatic Biology and Fisheries, University of Kerala, Beach PO., Trivandrum - 695 007 Kerala, India)
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